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sneak/dnswatcher:main sneak/dnswatcher:issue-166-entrypoint-data-dir sneak/dnswatcher:issue-164-livednstest sneak/dnswatcher:next sneak/dnswatcher:fix/98-security-headers sneak/dnswatcher:prod sneak/dnswatcher:fix/117-bootstrap-pin sneak/dnswatcher:fix/121-lint-cache-isolation sneak/dnswatcher:fix/115-cibuild-cache sneak/dnswatcher:fix/empty-targets-validation sneak/dnswatcher:fix/67-readme-api-endpoints sneak/dnswatcher:fix/issue-39-repo-policies sneak/dnswatcher:fix/issue-35-retry-timeout sneak/dnswatcher:fix/mock-resolver-tests sneak/dnswatcher:fix/dns-timeout-and-root-fanout sneak/dnswatcher:fix/query-timeout-and-recursive-resolution sneak/dnswatcher:fix/make-check-resolver-tests
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compare: sneak/dnswatcher:fix/empty-targets-validation
Branches Tags
sneak/dnswatcher:issue-166-entrypoint-data-dir sneak/dnswatcher:issue-164-livednstest sneak/dnswatcher:next sneak/dnswatcher:fix/98-security-headers sneak/dnswatcher:main sneak/dnswatcher:prod sneak/dnswatcher:fix/117-bootstrap-pin sneak/dnswatcher:fix/121-lint-cache-isolation sneak/dnswatcher:fix/115-cibuild-cache sneak/dnswatcher:fix/empty-targets-validation sneak/dnswatcher:fix/67-readme-api-endpoints sneak/dnswatcher:fix/issue-39-repo-policies sneak/dnswatcher:fix/issue-35-retry-timeout sneak/dnswatcher:fix/mock-resolver-tests sneak/dnswatcher:fix/dns-timeout-and-root-fanout sneak/dnswatcher:fix/query-timeout-and-recursive-resolution sneak/dnswatcher:fix/make-check-resolver-tests
1 Commits
18eba18759 .. fix/empty-targets-validation
Author SHA1 Message Date
user 713a2b7332 config: fail fast when DNSWATCHER_TARGETS is empty
check / check (push) Successful in 45s
Details 
When DNSWATCHER_TARGETS is empty or unset (the default), dnswatcher now
exits with a clear error message instead of silently starting with
nothing to monitor.

Added ErrNoTargets sentinel error returned from config.New when both
domains and hostnames lists are empty after target classification. This
causes the fx application to fail to start, preventing silent
misconfiguration.

Also extracted classifyAndValidateTargets and parseDurationOrDefault
helper functions to keep buildConfig within the funlen limit.

Closes #69
 2026-03-01 16:22:27 -08:00
74 changed files with 1086 additions and 9344 deletions
Expand all files Collapse all files
.gitea/workflows/check.yml
+1 -1
View File
@@ -6,4 +6,4 @@ jobs:
steps:
# actions/checkout v4.2.2, 2026-02-28
- uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
- run: script/cibuild
- run: docker build .
.golangci.yml
+14 -82
View File
@@ -1,100 +1,32 @@
version: "2"
# Config schema uses the golangci-lint v2 layout (settings live under
# linters.settings, not top-level linters-settings) so that the
# thresholds below are actually applied by golangci-lint >= v2.
run:
timeout: 5m
modules-download-mode: readonly
linters:
default: all
enable:
# Successor to the deprecated gomodguard. Named explicitly, rather than
# left to `default: all`, because it carries the module policy below.
- gomodguard_v2
disable:
# Genuinely incompatible with project patterns
- exhaustruct # Requires all struct fields
- depguard # Dependency allow/block lists
- godot # Requires comments to end with periods
- wsl # Deprecated, replaced by wsl_v5
- wrapcheck # Too verbose for internal packages
- varnamelen # Short names like db, id are idiomatic Go
# Deprecated: the warning is attached to the old name, so it is
# silenced by disabling that name, not by enabling the successor.
- wsl # Deprecated, replaced by wsl_v5
- gomodguard # Deprecated, replaced by gomodguard_v2
settings:
lll:
line-length: 88
funlen:
lines: 80
statements: 50
cyclop:
max-complexity: 15
dupl:
threshold: 100
depguard:
# Test-support code must not be compiled into the shipped binary. A
# test-support package exists to hand a test privileges the program
# itself must never have, so a file that is not a test must not import
# one. Test files, and the files inside a package whose directory name
# ends in `test`, are where that code belongs, and are exempt.
#
# The deny list below is the one part of this file a repository is
# expected to extend, and the only part it may. depguard matches an
# import path against a list of prefixes, so it cannot be told "any path
# whose last segment ends in test"; a repository's own test-support
# packages have to be named here one at a time, by full import path,
# under a module path that differs from repository to repository. Add
# them; change nothing else.
rules:
test-support:
list-mode: lax
files:
- "$all"
- "!$test"
- "!**/*test/**"
deny:
- pkg: net/http/httptest
desc: >-
Test-support code belongs in test files and in packages whose
directory name ends in test, not in the shipped binary.
- pkg: sneak.berlin/go/dnswatcher/internal/livednstest
desc: Live-DNS test support belongs in test files only.
# Only decisions already recorded in the Go package defaults are
# listed here. Every entry matches the module path exactly.
gomodguard_v2:
blocked:
- module: github.com/rs/zerolog
recommendations:
- log/slog
reason: "Structured logging is stdlib log/slog."
# One entry per pre-fork module path, because the later releases
# are separate paths. A prefix match would be shorter but would
# also reach github.com/go-redis/redismock, the test double for
# the successor these entries recommend.
- module: github.com/go-redis/redis
recommendations:
- github.com/redis/go-redis/v9
reason: "Pre-fork module; use the maintained go-redis v9."
- module: github.com/go-redis/redis/v7
recommendations:
- github.com/redis/go-redis/v9
reason: "Pre-fork module; use the maintained go-redis v9."
- module: github.com/go-redis/redis/v8
recommendations:
- github.com/redis/go-redis/v9
reason: "Pre-fork module; use the maintained go-redis v9."
- module: github.com/sergi/go-diff
recommendations:
- github.com/aymanbagabas/go-udiff
reason: "No unified diff output; use go-udiff."
- module: github.com/hexops/gotextdiff
recommendations:
- github.com/aymanbagabas/go-udiff
reason: "Unmaintained fork; use go-udiff."
linters-settings:
lll:
line-length: 88
funlen:
lines: 80
statements: 50
cyclop:
max-complexity: 15
dupl:
threshold: 100
issues:
exclude-use-default: false
max-issues-per-linter: 0
max-same-issues: 0
Dockerfile
+12 -46
View File
@@ -1,29 +1,13 @@
# Lint stage - fast feedback on lint issues, before the build starts.
# The linter is invoked directly rather than through `make lint`: that
# target shells out to `docker build -f Dockerfile.lint`, and there is
# no docker daemon inside a docker build.
# script/cibuild and script/docker name this stage in --no-cache-filter.
# golangci/golangci-lint:v2.12.2 (Debian-based), 2026-08-10
FROM golangci/golangci-lint:v2.12.2@sha256:5cceeef04e53efe1470638d4b4b4f5ceefd574955ab3941b2d9a68a8c9ad5240 AS lint
WORKDIR /src
COPY go.mod go.sum ./
RUN go mod download
COPY . .
RUN make fmt-check
RUN golangci-lint run --config .golangci.yml ./...
# Build stage
# script/cibuild and script/docker name this stage in --no-cache-filter.
# golang 1.25-alpine, 2026-02-28
FROM golang@sha256:f6751d823c26342f9506c03797d2527668d095b0a15f1862cddb4d927a7a4ced AS builder
RUN apk add --no-cache git make gcc musl-dev binutils-gold
# Force BuildKit to run the lint stage before proceeding
COPY --from=lint /src/go.sum /dev/null
# golangci-lint v2.10.1
RUN go install github.com/golangci/golangci-lint/v2/cmd/golangci-lint@5d1e709b7be35cb2025444e19de266b056b7b7ee
# goimports v0.42.0
RUN go install golang.org/x/tools/cmd/goimports@009367f5c17a8d4c45a961a3a509277190a9a6f0
WORKDIR /src
COPY go.mod go.sum ./
@@ -31,8 +15,8 @@ RUN go mod download
COPY . .
# Run the tests - build fails if any test fails
RUN make test
# Run all checks - build fails if any check fails
RUN make check
# Build the binary
RUN make build
@@ -43,33 +27,15 @@ FROM alpine@sha256:c3f8e73fdb79deaebaa2037150150191b9dcbfba68b4a46d70103204c53f4
RUN apk add --no-cache ca-certificates tzdata
COPY --from=builder /src/bin/dnswatcher /usr/local/bin/dnswatcher
WORKDIR /app
# Run as an unprivileged user that owns the data directory. A fresh named
# volume inherits this ownership; a bind-mounted host directory must be
# owned by uid 10001 (see "Running under upaas" in README.md), or startup
# fails.
RUN addgroup -S -g 10001 dnswatcher \
&& adduser -S -G dnswatcher -u 10001 dnswatcher \
&& mkdir -p /var/lib/dnswatcher \
&& chown dnswatcher:dnswatcher /var/lib/dnswatcher
COPY --from=builder /src/bin/dnswatcher /app/dnswatcher
# Create data directory
RUN mkdir -p /var/lib/dnswatcher
ENV DNSWATCHER_DATA_DIR=/var/lib/dnswatcher
# Config loading also reads a `.env` file and a file named `dnswatcher`
# (any config extension, or none) from the working directory. `/` holds
# neither, so every setting comes from the environment. Do not make the
# data directory, or the binary's directory, the working directory.
WORKDIR /
USER dnswatcher
EXPOSE 8080
# busybox wget (already in alpine) probes the health endpoint every 10
# seconds, so the container is healthy well before upaas reads its health
# 60 seconds after a deploy and fails the deploy unless it is healthy.
HEALTHCHECK --interval=10s --timeout=5s --start-period=10s --retries=3 \
CMD wget -q -O /dev/null "http://127.0.0.1:${PORT:-8080}/.well-known/healthcheck" || exit 1
ENTRYPOINT ["/usr/local/bin/dnswatcher"]
ENTRYPOINT ["/app/dnswatcher"]
Dockerfile.lint
-29
View File
@@ -1,29 +0,0 @@
# Lint-only image: used by script/lint. golangci-lint is never run on
# the host — the repo is COPYed into the build context and the linter
# runs as a build step, so a successful build IS a clean lint. This
# also works where the docker daemon is remote and bind mounts are
# impossible.
#
# `golangci-lint config verify` is deliberately NOT run here: it
# fetches its JSON schema over a live, unpinned HTTPS call, which would
# make linting network-dependent and defeat hash-pinning. The cost of
# that: unknown top-level keys in .golangci.yml are silently ignored,
# so a mistyped or wrong-schema key lints clean while applying nothing.
#
# golangci/golangci-lint:v2.12.2 (Debian-based), 2026-08-10
FROM golangci/golangci-lint:v2.12.2@sha256:5cceeef04e53efe1470638d4b4b4f5ceefd574955ab3941b2d9a68a8c9ad5240 AS deps
WORKDIR /src
# Dependencies first, so this stage stays cached across lint runs.
COPY go.mod go.sum ./
RUN go mod download
# Everything below is invalidated on every run by the
# --no-cache-filter=lint that script/lint passes: caching is explicitly
# waived for linting, and a cached build lints nothing.
FROM deps AS lint
COPY . .
RUN golangci-lint run --config .golangci.yml ./...
LICENSE
-21
View File
@@ -1,21 +0,0 @@
MIT License
Copyright (c) 2026 sneak
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
Makefile
+30 -25
View File
@@ -1,44 +1,49 @@
.PHONY: all bootstrap setup build lint fmt fmt-check test check clean hooks docker
.PHONY: all build lint fmt fmt-check test check clean hooks docker
BINARY := dnswatcher
VERSION := $(shell git describe --tags --always --dirty 2>/dev/null || echo "dev")
LDFLAGS := -X main.Version=$(VERSION)
# Standard targets are thin shims; the implementations live in script/
# per the scripts-to-rule-them-all pattern (see the Entrypoints section
# of README.md).
BUILDARCH := $(shell go env GOARCH)
LDFLAGS := -X main.Version=$(VERSION) -X main.Buildarch=$(BUILDARCH)
all: check build
bootstrap:
@script/bootstrap
setup:
@script/setup
build:
go build -ldflags "$(LDFLAGS)" -o bin/$(BINARY) ./cmd/dnswatcher
test:
@script/test
lint:
@script/lint
golangci-lint run --config .golangci.yml ./...
fmt:
@script/fmt
gofmt -s -w .
goimports -w .
fmt-check:
@script/fmt-check
@test -z "$$(gofmt -l .)" || (echo "gofmt: files not formatted:" && gofmt -l . && exit 1)
test:
go test -v -race -timeout 30s -cover ./...
# Check runs all validation without making changes
# Used by CI and Docker build - fails if anything is wrong
check:
@script/check
docker:
@script/docker
hooks:
@script/install-precommit
@echo "==> Checking formatting..."
@test -z "$$(gofmt -l .)" || (echo "Files not formatted:" && gofmt -l . && exit 1)
@echo "==> Running linter..."
golangci-lint run --config .golangci.yml ./...
@echo "==> Running tests..."
go test -v -race -timeout 30s ./...
@echo "==> Building..."
go build -ldflags "$(LDFLAGS)" -o /dev/null ./cmd/dnswatcher
@echo "==> All checks passed!"
clean:
rm -rf bin/
hooks:
@echo '#!/bin/sh' > .git/hooks/pre-commit
@echo 'make check' >> .git/hooks/pre-commit
@chmod +x .git/hooks/pre-commit
@echo "Pre-commit hook installed."
docker:
docker build .
README.md
+29 -247
View File
@@ -1,6 +1,6 @@
# dnswatcher
dnswatcher is an MIT-licensed, pre-1.0 Go daemon by [@sneak](https://sneak.berlin) that monitors DNS records, TCP port availability, and TLS certificates, delivering real-time change notifications via Slack, Mattermost, and ntfy webhooks.
dnswatcher is a pre-1.0 Go daemon by [@sneak](https://sneak.berlin) that monitors DNS records, TCP port availability, and TLS certificates, delivering real-time change notifications via Slack, Mattermost, and ntfy webhooks.
> ⚠️ Pre-1.0 software. APIs, configuration, and behavior may change without notice.
@@ -17,26 +17,6 @@ without requiring an external database.
---
## No DNS mocking. Ever.
**DNS is never mocked in this project — not in tests, not anywhere else.**
No mock resolvers, no fake DNS servers, no stubbed lookups.
dnswatcher's entire purpose is correct behavior against the real DNS.
Tests exercise real iterative resolution against live nameservers by
design; a test suite that passes against a mock proves nothing about the
one thing this program exists to do.
When live tests are flaky, that is a robustness problem, and it gets
fixed with robustness: retries with backoff, querying multiple
independent nameservers, longer timeouts — or explicit opt-in gating
decided by the project owner. Never with mocks.
Contributions that introduce mocked, faked, or stubbed DNS will be
rejected.
---
## Features
### DNS Domain Monitoring (Apex Domains)
@@ -61,10 +41,6 @@ rejected.
record types: A, AAAA, CNAME, MX, TXT, SRV, CAA, NS.
- Stores results **per nameserver**. The state for a hostname is not a
merged view — it is a map from nameserver to record set.
- DNS names inside record values (CNAME, MX, SRV and NS targets) are
stored in lower case, because names are case-insensitive and
nameservers may answer in any letter case. TXT and CAA values keep
their letter case; they are not lower-cased.
- Any observable change in any nameserver's response triggers a
notification. This includes:
- **Record change**: A nameserver returns different records than it
@@ -74,15 +50,12 @@ rejected.
This is distinct from "responded with no records."
- **NS recovery**: A previously-unreachable nameserver starts
responding again.
- **Inconsistency detected**: Two nameservers return different record
sets for the same hostname and did not already differ on the previous
check. Every pair of nameservers is compared. The alert is sent once
for each such pair, on the check where they start to disagree, and not
again while they keep disagreeing, including after a restart. A
nameserver that was not in the previous check (newly added, or back
after dropping out) and answers differently is reported on the check
where it appears. If a pair agrees again and later disagrees, the
alert is sent again.
- **Inconsistency detected**: Two nameservers that previously agreed
now return different record sets for the same hostname.
- **Inconsistency resolved**: Nameservers that previously disagreed
are now back in agreement.
- **Empty response**: A nameserver that previously returned records
now returns an authoritative empty response (NODATA/NXDOMAIN).
### TCP Port Monitoring
@@ -155,105 +128,18 @@ includes:
- State is written atomically (write to temp file, then rename) to prevent
corruption.
### Web Dashboard
dnswatcher includes an unauthenticated, read-only web dashboard at the
root URL (`/`). It displays:
- **Summary counts** for monitored domains, hostnames, ports, and
certificates.
- **Domains** with their discovered nameservers.
- **Hostnames** with per-nameserver DNS records and status.
- **Ports** with open/closed state and associated hostnames.
- **TLS certificates** with CN, issuer, expiry, and status.
- **Recent alerts** (last 100 notifications sent since the process
started), displayed in reverse chronological order.
Every data point shows its age (e.g. "5m ago") so you can tell at a
glance how fresh the information is. The page auto-refreshes every 30
seconds.
The dashboard intentionally does not expose any configuration details
such as webhook URLs, notification endpoints, or API tokens.
All assets (CSS) are embedded in the binary and served from the
application itself. The dashboard makes zero external HTTP requests —
no CDN dependencies or third-party resources are loaded at runtime.
### HTTP API
dnswatcher exposes a lightweight HTTP API for operational visibility:
| Endpoint | Description |
|---------------------------------------|--------------------------------|
| `GET /` | Web dashboard (HTML) |
| `GET /s/...` | Static assets (embedded CSS) |
| `GET /.well-known/healthcheck` | Health check (JSON) |
| `GET /health` | Health check (JSON, legacy) |
| `GET /health` | Health check (JSON) |
| `GET /api/v1/status` | Current monitoring state |
| `GET /api/v1/domains` | Configured domains and status |
| `GET /api/v1/hostnames` | Configured hostnames and status|
| `GET /metrics` | Prometheus metrics (optional) |
#### Server timeouts
The HTTP server sets all four socket-level timeouts. These are compile-time
constants in `internal/server/server.go`, not configurable via environment
variables.
| Timeout | Value | Purpose |
|---------------------|-------|-----------------------------------------------|
| `ReadHeaderTimeout` | 10s | Bounds the request header read (slowloris) |
| `ReadTimeout` | 15s | Bounds the whole request read, headers + body |
| `WriteTimeout` | 75s | Bounds handler execution plus response flush |
| `IdleTimeout` | 120s | Reaps idle keep-alive connections |
These are distinct from the 60s per-request handler budget applied by
`chimw.Timeout` in `internal/server/routes.go`, which cancels the request
context but does not touch the socket. `WriteTimeout` is deliberately
larger than that budget: the write deadline is armed once request headers
are read, so a smaller value would sever the connection before a handler
using its full budget could respond. `IdleTimeout` exceeds common
Prometheus scrape intervals so the scraper reuses its connection.
### Security Headers
Every response — the dashboard, the static assets under `/s/...`, the
healthchecks, the JSON API, and `/metrics` — carries the following
headers, set by a global middleware:
| Header | Value |
|-----------------------------|---------------------------------------|
| `Strict-Transport-Security` | `max-age=31536000; includeSubDomains` |
| `Content-Security-Policy` | see below |
| `X-Frame-Options` | `DENY` |
| `X-Content-Type-Options` | `nosniff` |
| `Referrer-Policy` | `no-referrer` |
| `Permissions-Policy` | all unused browser features denied |
The content security policy is:
```
default-src 'self'; script-src 'none'; style-src 'self'; img-src 'self';
font-src 'none'; connect-src 'none'; object-src 'none'; base-uri 'none';
form-action 'none'; frame-ancestors 'none'
```
The dashboard ships no JavaScript (the 30-second refresh is a
`<meta http-equiv="refresh">`), no inline styles, no inline event
handlers, and no images; its only subresource is the embedded stylesheet
at `/s/css/tailwind.min.css`, which `style-src 'self'` permits. The
policy therefore needs neither `unsafe-inline` nor `unsafe-eval`.
`frame-ancestors 'none'` is the primary anti-framing control, with
`X-Frame-Options: DENY` retained as the legacy fallback.
HSTS is emitted unconditionally, including over plain HTTP. dnswatcher is
expected to run behind a TLS-terminating reverse proxy, and the browser
must still be told to enforce HTTPS end to end, so the header is never
gated on whether the request itself arrived over TLS.
`Referrer-Policy: no-referrer` is stricter than the
`strict-origin-when-cross-origin` baseline: the dashboard has no
cross-origin navigation needs, and its URL may name internal hosts.
---
## Architecture
@@ -263,11 +149,10 @@ cmd/dnswatcher/main.go Entry point (uber/fx bootstrap)
internal/
config/config.go Viper-based configuration
globals/globals.go Build-time variables (version)
globals/globals.go Build-time variables (version, arch)
logger/logger.go slog structured logging (TTY detection)
healthcheck/healthcheck.go Health check service
middleware/middleware.go HTTP middleware (logging, CORS, security
headers, metrics auth)
middleware/middleware.go HTTP middleware (logging, CORS, metrics auth)
handlers/handlers.go HTTP request handlers
server/
server.go HTTP server lifecycle
@@ -278,8 +163,6 @@ internal/
tlscheck/tlscheck.go TLS certificate inspector
notify/notify.go Notification service (Slack, Mattermost, ntfy)
watcher/watcher.go Main monitoring orchestrator and scheduler
livednstest/livednstest.go Retry and concurrency limit for tests
against live DNS (imported only by tests)
```
### Design Principles
@@ -293,8 +176,7 @@ internal/
- **Structured logging**: All logs use `log/slog` with JSON output in
production (TTY detection for development).
- **Graceful shutdown**: All background goroutines respect context
cancellation and the fx lifecycle. In-flight notification deliveries
are drained on shutdown, bounded by the shutdown timeout.
cancellation and the fx lifecycle.
---
@@ -315,7 +197,7 @@ the following precedence (highest to lowest):
|---------------------------------|--------------------------------------------|-------------|
| `PORT` | HTTP listen port | `8080` |
| `DNSWATCHER_DEBUG` | Enable debug logging | `false` |
| `DNSWATCHER_DATA_DIR` | Directory for state file | `/var/lib/dnswatcher` |
| `DNSWATCHER_DATA_DIR` | Directory for state file | `./data` |
| `DNSWATCHER_TARGETS` | Comma-separated DNS names (auto-classified via PSL) | `""` |
| `DNSWATCHER_SLACK_WEBHOOK` | Slack incoming webhook URL | `""` |
| `DNSWATCHER_MATTERMOST_WEBHOOK` | Mattermost incoming webhook URL | `""` |
@@ -327,25 +209,17 @@ the following precedence (highest to lowest):
| `DNSWATCHER_MAINTENANCE_MODE` | Enable maintenance mode | `false` |
| `DNSWATCHER_METRICS_USERNAME` | Basic auth username for /metrics | `""` |
| `DNSWATCHER_METRICS_PASSWORD` | Basic auth password for /metrics | `""` |
| `DNSWATCHER_SEND_TEST_NOTIFICATION` | Send a test notification after first scan completes | `false` |
**`DNSWATCHER_TARGETS` is required.** dnswatcher will refuse to start if no
monitoring targets are configured. A monitoring daemon with nothing to monitor
is a misconfiguration, so dnswatcher fails fast with a clear error message
rather than running silently. Set `DNSWATCHER_TARGETS` to a comma-separated
list of DNS names before starting.
### Example `.env`
```sh
PORT=8080
DNSWATCHER_DEBUG=false
DNSWATCHER_DATA_DIR=/var/lib/dnswatcher
DNSWATCHER_DATA_DIR=./data
DNSWATCHER_TARGETS=example.com,example.org,www.example.com,api.example.com,mail.example.org
DNSWATCHER_SLACK_WEBHOOK=https://hooks.slack.com/services/T.../B.../xxx
DNSWATCHER_MATTERMOST_WEBHOOK=https://mattermost.example.com/hooks/xxx
DNSWATCHER_NTFY_TOPIC=https://ntfy.sh/my-dns-alerts
DNSWATCHER_SEND_TEST_NOTIFICATION=true
```
---
@@ -445,67 +319,29 @@ tracks reachability:
|-------------|-------------------------------------------------|
| `ok` | Query succeeded, records are current |
| `error` | Query failed (timeout, SERVFAIL, network error) |
| `nxdomain` | Authoritative NXDOMAIN response |
| `nodata` | Authoritative empty response (NODATA) |
---
## Entrypoints
This repository adheres to the
[Scripts to Rule Them All](https://github.com/github/scripts-to-rule-them-all)
standard: normalized scripts in `script/` are the entrypoints for the
development workflow, and the Makefile targets are thin shims that call
them. We provide:
- `script/bootstrap` — install all dependencies (go, pinned goimports,
`go mod download`). It does not install golangci-lint: see
`script/lint` below.
- `script/setup` — make a fresh clone ready for development: bootstrap
plus the git pre-commit hook
- `script/projectname` — print the project name (used for the Docker
image tag)
- `script/test` — run the test suite (race detector, coverage). Caching
is waived for testing, exactly as it is for linting: `-count=1`
forces every invocation to execute, because the suite queries live
DNS and a cached pass queries nothing. Failures are rerun with `-v`
automatically, and the build fails even if that rerun passes.
- `script/lint` — run golangci-lint, always inside Docker: it builds
`Dockerfile.lint`, which COPYs the repo into the digest-pinned
`golangci-lint` image and lints as a build step, so a successful
build is a clean lint. The linter is never installed or run on the
host, and Docker is the only prerequisite. Caching is waived for
linting: the lint stage is forced to execute on every run with
`--no-cache-filter`, because a cached build lints nothing.
- `script/fmt` — format all code (gofmt -s, goimports)
- `script/fmt-check` — check formatting (read-only)
- `script/check` — run test, lint, and fmt-check
- `script/docker` — build the Docker image tagged via `script/projectname`, with
`--no-cache-filter=lint,builder` so the lint stage and the builder stage,
which runs the tests, run on every invocation
- `script/cibuild` — CI entrypoint: `docker build` with
`--no-cache-filter=lint,builder`, so the lint stage and the builder stage,
which runs the tests, run on every invocation, because a cached build lints
nothing and queries no DNS
- `script/precommit` — run by the git pre-commit hook; `go mod tidy`
guard, then `script/check`
- `script/install-precommit` — install the git pre-commit hook
## Building
```sh
make build # Build binary to bin/dnswatcher
make test # Run tests with race detector
make lint # Run golangci-lint in Docker (requires docker)
make lint # Run golangci-lint
make fmt # Format code
make check # Run all checks (test, lint, fmt-check)
make check # Run all checks (format, lint, test, build)
make clean # Remove build artifacts
```
### Build-Time Variables
Version is injected via `-ldflags`:
Version and architecture are injected via `-ldflags`:
```sh
go build -ldflags "-X main.Version=$(git describe --tags --always)" ./cmd/dnswatcher
go build -ldflags "-X main.Version=$(git describe --tags --always) \
-X main.Buildarch=$(go env GOARCH)" ./cmd/dnswatcher
```
---
@@ -519,63 +355,16 @@ docker run -d \
-v dnswatcher-data:/var/lib/dnswatcher \
-e DNSWATCHER_TARGETS=example.com,www.example.com \
-e DNSWATCHER_NTFY_TOPIC=https://ntfy.sh/my-alerts \
-e DNSWATCHER_SEND_TEST_NOTIFICATION=true \
dnswatcher
```
---
## Running under upaas
[upaas](https://git.eeqj.de/sneak/upaas) builds the image from this
repository's `Dockerfile` and runs it. The app needs:
- **Branch:** `prod`. `prod` is cut from `main`, and merging a `main` to
`prod` pull request is a deploy.
- **Volume:** one host directory mounted at `/var/lib/dnswatcher`, where
the state file lives. upaas bind-mounts the host path it is given and
does not create it. The container runs as uid 10001 and does not start
unless it can write there. Create the directory before the first
deploy:
```sh
mkdir -p /path/to/data
chown 10001:10001 /path/to/data
chmod 700 /path/to/data
```
- **Network and port:** the dashboard is unauthenticated and shows every
watched name and recent alert, and upaas publishes every mapped port on
all interfaces of the host
([upaas issue 113](https://git.eeqj.de/sneak/upaas/issues/113)). Add a
port mapping to container port `8080` only if the dashboard should be
public. Otherwise add none: set the app's Docker network in upaas to
your reverse proxy's Docker network, and the proxy reaches the app at
`upaas-` followed by the app name, port `8080`.
- **Required environment:** `DNSWATCHER_TARGETS`, a comma-separated list
of the domains and hostnames to watch. dnswatcher refuses to start
without it.
- **Recommended environment:** at least one notification endpoint
(`DNSWATCHER_SLACK_WEBHOOK`, `DNSWATCHER_MATTERMOST_WEBHOOK`,
`DNSWATCHER_NTFY_TOPIC`); without one, changes show only on the
dashboard. `DNSWATCHER_METRICS_USERNAME` and
`DNSWATCHER_METRICS_PASSWORD` serve `/metrics` behind basic auth.
- **Leave unset:** `DNSWATCHER_DATA_DIR`, which the image sets to
`/var/lib/dnswatcher`, and `PORT`, which defaults to `8080`. Every
setting comes from the environment; the image holds no config file.
- **Health check:** the image's own, which requests
`/.well-known/healthcheck` every 10 seconds. upaas reads the
container's health 60 seconds after a deploy and marks the deploy
failed unless it is `healthy`.
---
## Monitoring Lifecycle
1. **Startup**: Check that the data directory can be written, and exit
with an error naming it if not. Load state from disk. If no state
file exists, start with empty state (first check will establish
baseline without triggering change notifications).
1. **Startup**: Load state from disk. If no state file exists, start
with empty state (first check will establish baseline without
triggering change notifications).
2. **Initial check**: Immediately perform all DNS, port, and TLS checks
on startup.
3. **Periodic checks** (DNS always runs first):
@@ -589,14 +378,8 @@ repository's `Dockerfile` and runs it. The app needs:
from a previous cycle.
4. **On change detection**: Send notifications to all configured
endpoints, update in-memory state, persist to disk.
5. **Shutdown**: Persist final state to disk, wait for in-flight
notification deliveries to complete, stop gracefully. The wait is
bounded by the fx shutdown timeout (15s by default): deliveries still
retrying against an unreachable endpoint when that expires are
abandoned, and the number abandoned is logged at warn level rather
than dropped silently. Notifications generated after shutdown has
begun are refused and logged, so a late burst cannot extend the
shutdown.
5. **Shutdown**: Persist final state to disk, complete in-flight
notifications, stop gracefully.
---
@@ -618,9 +401,8 @@ Viper for configuration.
## License
dnswatcher is released under the MIT License, Copyright (c) 2026
[@sneak](https://sneak.berlin). See the [`LICENSE`](./LICENSE) file in the
repository root for the full text.
License has not yet been chosen for this project. Pending decision by the
author (MIT, GPL, or WTFPL).
## Author
REPO_POLICIES.md
+21 -249
View File
@@ -1,6 +1,6 @@
---
title: Repository Policies
last_modified: 2026-08-07
last_modified: 2026-02-22
---
This document covers repository structure, tooling, and workflow standards. Code
@@ -34,46 +34,10 @@ style conventions are in separate documents:
every file before committing. There are zero exceptions to this rule.
- Every repo with software must have a root `Makefile` with these targets:
`make bootstrap`, `make setup`, `make test`, `make lint`, `make fmt` (writes),
`make fmt-check` (read-only), `make check` (runs `test`, `lint`, `fmt-check`),
`make docker`, and `make hooks` (installs pre-commit hook). A model Makefile
is at `https://git.eeqj.de/sneak/prompts/raw/branch/main/Makefile`.
- Repos follow the
[Scripts to Rule Them All](https://github.com/github/scripts-to-rule-them-all)
pattern: the implementation of each Makefile target lives in an executable
script in `script/` (`script/bootstrap`, `script/setup`, `script/test`,
`script/lint`, `script/fmt`, `script/fmt-check`, `script/check`,
`script/docker`), and the Makefile targets are thin shims that call them. The
scripts must be POSIX sh (`#!/bin/sh`, `set -eu`, no bashisms) so they run in
minimal containers (e.g. alpine images have no bash); locate the repo root
with `$(cd "$(dirname "$0")/.." && pwd -P)` and `cd` there before acting. From
the standard's canonical set we use `bootstrap`, `setup` (make the repo ready
for development after a fresh clone: runs `bootstrap`, then
`install-precommit`, plus any repo-specific initialization), `test`, and
`cibuild`. `script/bootstrap` installs all dependencies idempotently and
assumes nothing is present: base tools come from nix, apt, brew, or apk
(detected in that order; apt runs noninteractive). For node it uses the
installed node if present; otherwise it installs a PINNED node version via
nvm, first installing nvm itself if missing — from a hash-verified GitHub
release archive (never `curl | sh`), with bash installed as an explicit
prerequisite since nvm requires bash. yarn is then pinned via
`corepack prepare yarn@<version> --activate`. Never install "latest" or "lts";
always exact versions. `script/cibuild` runs the CI build: it changes to the
repo root and runs `docker build .`; the Gitea workflow calls it. Four further
scripts are our own extensions to the standard: `script/check` runs
`script/test`, `script/lint`, and `script/fmt-check`; `script/precommit` is
what the git pre-commit hook runs, and it calls `script/check`;
`script/install-precommit` installs the git pre-commit hook (the `make hooks`
target shims to it); and `script/projectname` (literally that filename) simply
outputs the project's name. Scripts that need the name call
`script/projectname` — e.g. `script/docker` assembles its image tag from it —
so those scripts stay byte-identical across all repos. Repo-type-specific
pre-commit extras (e.g. `go mod tidy` verification in Go repos) belong in
`script/precommit`, not in the hook itself. Model scripts are at
`https://git.eeqj.de/sneak/prompts/raw/branch/main/script/<name>`. The README
must document the provided scripts in an **Entrypoints** section (see the
README requirements below).
`make test`, `make lint`, `make fmt` (writes), `make fmt-check` (read-only),
`make check` (prereqs: `test`, `lint`, `fmt-check`), `make docker`, and
`make hooks` (installs pre-commit hook). A model Makefile is at
`https://git.eeqj.de/sneak/prompts/raw/branch/main/Makefile`.
- Always use Makefile targets (`make fmt`, `make test`, `make lint`, etc.)
instead of invoking the underlying tools directly. The Makefile is the single
@@ -93,83 +57,11 @@ style conventions are in separate documents:
as a build step so the build fails if the branch is not green. For non-server
repos, the Dockerfile should bring up a development environment and run
`make check`. For server repos, `make check` should run as an early build
stage before the final image is assembled. Dockerfiles install development
prerequisites by running `script/bootstrap` rather than duplicating installs
inline; COPY `script/` and the dependency manifests (`package.json` +
`yarn.lock`, `go.mod` + `go.sum`, etc.) before running it so the bootstrap
layer stays cached until dependencies change.
- **Dockerfiles must use a separate lint stage for fail-fast feedback.** Go
repos use a multistage build where linting runs in an independent stage based
on the `golangci/golangci-lint` image (pinned by hash). This stage runs
`make fmt-check` and `make lint` before the full build begins. The build stage
then declares an explicit dependency on the lint stage via
`COPY --from=lint /src/go.sum /dev/null`, which forces BuildKit to complete
linting before proceeding to compilation and tests. This ensures lint failures
surface in seconds rather than minutes, without blocking on dependency
download or compilation in the build stage.
The standard pattern for a Go repo Dockerfile is:
```dockerfile
# Lint stage — fast feedback on formatting and lint issues
# golangci/golangci-lint:v2.x.x, YYYY-MM-DD
FROM golangci/golangci-lint@sha256:... AS lint
WORKDIR /src
COPY go.mod go.sum ./
RUN go mod download
COPY . .
RUN make fmt-check
RUN make lint
# Build stage
# golang:1.x-alpine, YYYY-MM-DD
FROM golang@sha256:... AS builder
WORKDIR /src
# Force BuildKit to run the lint stage before proceeding
COPY --from=lint /src/go.sum /dev/null
COPY go.mod go.sum ./
RUN go mod download
COPY . .
RUN make test
ARG VERSION=dev
RUN CGO_ENABLED=0 go build -trimpath \
-ldflags="-s -w -X main.Version=${VERSION}" \
-o /app ./cmd/app/
# Runtime stage
FROM alpine@sha256:...
COPY --from=builder /app /usr/local/bin/app
ENTRYPOINT ["app"]
```
Key points:
- The lint stage uses the `golangci/golangci-lint` image directly (it
includes both Go and the linter), so there is no need to install the
linter separately.
- `COPY --from=lint /src/go.sum /dev/null` is a no-op file copy that creates
a stage dependency. BuildKit runs stages in parallel by default; without
this line, the build stage would not wait for lint to finish and a lint
failure might not fail the overall build.
- If the project uses `//go:embed` directives that reference build artifacts
(e.g. a web frontend compiled in a separate stage), the lint stage must
create placeholder files so the embed directives resolve. Example:
`RUN mkdir -p web/dist && touch web/dist/index.html web/dist/style.css`.
The lint stage should not depend on the actual build output — it exists to
fail fast.
- If the project requires CGO or system libraries for linting (e.g.
`vips-dev`), install them in the lint stage with `apk add`.
- The build stage runs `make test` after compilation setup. Tests run in the
build stage, not the lint stage, because they may require compiled
artifacts or heavier dependencies.
stage before the final image is assembled.
- Every repo should have a Gitea Actions workflow (`.gitea/workflows/`) that
runs `script/cibuild` (which runs `docker build .`) on push. Since the
Dockerfile already runs `make check`, a successful build implies all checks
pass.
runs `docker build .` on push. Since the Dockerfile already runs `make check`,
a successful build implies all checks pass.
- Use platform-standard formatters: `black` for Python, `prettier` for
JS/CSS/Markdown/HTML, `go fmt` for Go. Always use default configuration with
@@ -177,11 +69,9 @@ style conventions are in separate documents:
Markdown (hard-wrap at 80 columns). Documentation and writing repos (Markdown,
HTML, CSS) should also have `.prettierrc` and `.prettierignore`.
- Pre-commit hook: runs `script/precommit`, which calls `script/check`. If local
testing is not possible in the repo, `script/precommit` may skip `script/test`
and run only `script/lint` and `script/fmt-check`. The hook is installed by
`script/install-precommit`; the Makefile must provide a `make hooks` target
that shims to it.
- Pre-commit hook: `make check` if local testing is possible, otherwise
`make lint && make fmt-check`. The Makefile should provide a `make hooks`
target to install the pre-commit hook.
- All repos with software must have tests that run via the platform-standard
test framework (`go test`, `pytest`, `jest`/`vitest`, etc.). If no meaningful
@@ -189,49 +79,8 @@ style conventions are in separate documents:
module under test to verify it compiles/parses. There is no excuse for
`make test` to be a no-op.
- `make test` must complete in under 60 seconds. That is the hard cap, and a
suite that exceeds it fails. Under 20 seconds is the target. A suite between
20 and 60 seconds is still green, but the overage must be filed as an
improvement bug against that repo. Add a 90-second timeout to the test
invocation in the Makefile (`go test -timeout 90s`). The backstop deliberately
sits above the hard cap so that it catches a genuinely hung test rather than a
merely slow one.
- **`make test` should use the conditional verbose rerun pattern.** Run tests
without `-v` (verbose) first. If tests fail, automatically rerun with `-v` to
show full output. This keeps CI logs and `docker build` output clean on
success (just package/suite summaries) while providing full diagnostic detail
on failure (every test case, every assertion). The general shell pattern:
```makefile
test:
@<test-command> || \
{ echo "--- Rerunning with -v for details ---"; \
<test-command-with-v>; exit 1; }
```
Go example:
```makefile
test:
@go test -timeout 90s -race -cover ./... || \
{ echo "--- Rerunning with -v for details ---"; \
go test -timeout 90s -race -v ./...; exit 1; }
```
Python example:
```makefile
test:
@python -m pytest || \
{ echo "--- Rerunning with -v for details ---"; \
python -m pytest -v; exit 1; }
```
The `exit 1` ensures the target always fails after a rerun — the first run
already proved the tests are broken, so the build must not pass even if a
flaky test happens to succeed on the second attempt. The rerun exists solely
for diagnostic output.
- `make test` must complete in under 20 seconds. Add a 30-second timeout in the
Makefile.
- Docker builds must complete in under 5 minutes.
@@ -249,13 +98,6 @@ style conventions are in separate documents:
`https://git.eeqj.de/sneak/prompts/raw/branch/main/.gitignore` when setting up
a new repo.
- **No build artifacts in version control.** Code-derived data (compiled
bundles, minified output, generated assets) must never be committed to the
repository if it can be avoided. The build process (e.g. Dockerfile, Makefile)
should generate these at build time. Notable exception: Go protobuf generated
files (`.pb.go`) ARE committed because repos need to work with `go get`, which
downloads code but does not execute code generation.
- Never use `git add -A` or `git add .`. Always stage files explicitly by name.
- Never force-push to `main`.
@@ -265,10 +107,7 @@ style conventions are in separate documents:
- `.golangci.yml` is standardized and must _NEVER_ be modified by an agent, only
manually by the user. Fetch from
`https://git.eeqj.de/sneak/prompts/raw/branch/main/.golangci.yml`. The
canonical golangci-lint version is v2.12.2 (released 2026-05-06), installed
commit-pinned via
`go install github.com/golangci/golangci-lint/v2/cmd/golangci-lint@c0d3ddc9cf3faa61a4e378e879ece580256d76e5`.
`https://git.eeqj.de/sneak/prompts/raw/branch/main/.golangci.yml`.
- When pinning images or packages by hash, add a comment above the reference
with the version and date (YYYY-MM-DD).
@@ -282,76 +121,12 @@ style conventions are in separate documents:
- Dockerized web services listen on port 8080 by default, overridable with
`PORT`.
- **HTTP/web services must be hardened for production internet exposure before
tagging 1.0.** This means full compliance with security best practices
including, without limitation, all of the following:
- **Security headers** on every response:
- `Strict-Transport-Security` (HSTS) with `max-age` of at least one year
and `includeSubDomains`.
- `Content-Security-Policy` (CSP) with a restrictive default policy
(`default-src 'self'` as a baseline, tightened per-resource as
needed). Never use `unsafe-inline` or `unsafe-eval` unless
unavoidable, and document the reason.
- `X-Frame-Options: DENY` (or `SAMEORIGIN` if framing is required).
Prefer the `frame-ancestors` CSP directive as the primary control.
- `X-Content-Type-Options: nosniff`.
- `Referrer-Policy: strict-origin-when-cross-origin` (or stricter).
- `Permissions-Policy` restricting access to browser features the
application does not use (camera, microphone, geolocation, etc.).
- **Request and response limits:**
- Maximum request body size enforced on all endpoints (e.g. Go
`http.MaxBytesReader`). Choose a sane default per-route; never accept
unbounded input.
- Maximum response body size where applicable (e.g. paginated APIs).
- `ReadTimeout` and `ReadHeaderTimeout` on the `http.Server` to defend
against slowloris attacks.
- `WriteTimeout` on the `http.Server`.
- `IdleTimeout` on the `http.Server`.
- Per-handler execution time limits via `context.WithTimeout` or
chi/stdlib `middleware.Timeout`.
- **Authentication and session security:**
- Rate limiting on password-based authentication endpoints. API keys are
high-entropy and not susceptible to brute force, so they are exempt.
- CSRF tokens on all state-mutating HTML forms. API endpoints
authenticated via `Authorization` header (Bearer token, API key) are
exempt because the browser does not attach these automatically.
- Passwords stored using bcrypt, scrypt, or argon2 — never plain-text,
MD5, or SHA.
- Session cookies set with `HttpOnly`, `Secure`, and `SameSite=Lax` (or
`Strict`) attributes.
- **Reverse proxy awareness:**
- True client IP detection when behind a reverse proxy
(`X-Forwarded-For`, `X-Real-IP`). The application must accept
forwarded headers only from a configured set of trusted proxy
addresses — never trust `X-Forwarded-For` unconditionally.
- **CORS:**
- Authenticated endpoints must restrict `Access-Control-Allow-Origin` to
an explicit allowlist of known origins. Wildcard (`*`) is acceptable
only for public, unauthenticated read-only APIs.
- **Error handling:**
- Internal errors must never leak stack traces, SQL queries, file paths,
or other implementation details to the client. Return generic error
messages in production; detailed errors only when `DEBUG` is enabled.
- **TLS:**
- Services never terminate TLS directly. They are always deployed behind
a TLS-terminating reverse proxy. The service itself listens on plain
HTTP. However, HSTS headers and `Secure` cookie flags must still be
set by the application so that the browser enforces HTTPS end-to-end.
This list is non-exhaustive. Apply defense-in-depth: if a standard security
hardening measure exists for HTTP services and is not listed here, it is
still expected. When in doubt, harden.
- `README.md` is the primary documentation. Required sections:
- **Description**: First line must include the project name, purpose,
category (web server, SPA, CLI tool, etc.), license, and author. Example:
"µPaaS is an MIT-licensed Go web application by @sneak that receives
git-frontend webhooks and deploys applications via Docker in realtime."
- **Getting Started**: Copy-pasteable install/usage code block.
- **Entrypoints**: Opens by stating that the repo adheres to the
[Scripts to Rule Them All](https://github.com/github/scripts-to-rule-them-all)
standard (with that link), then documents each provided `script/`
entrypoint and its purpose.
- **Rationale**: Why does this exist?
- **Design**: How is the program structured?
- **TODO**: Update meticulously, even between commits. When planning, put
@@ -370,13 +145,13 @@ style conventions are in separate documents:
- Database migrations live in `internal/db/migrations/` and must be embedded in
the binary.
- `000_migration.sql` — contains ONLY the creation of the migrations
tracking table itself. Nothing else.
- `001_schema.sql` — the full application schema.
- **Pre-1.0.0:** never add additional migration files (002, 003, etc.).
There is no installed base to migrate. Edit `001_schema.sql` directly.
- **Post-1.0.0:** add new numbered migration files for each schema change.
Never edit existing migrations after release.
- `000_migration.sql` — contains ONLY the creation of the migrations tracking
table itself. Nothing else.
- `001_schema.sql` — the full application schema.
- **Pre-1.0.0:** never add additional migration files (002, 003, etc.). There
is no installed base to migrate. Edit `001_schema.sql` directly.
- **Post-1.0.0:** add new numbered migration files for each schema change.
Never edit existing migrations after release.
- All repos should have an `.editorconfig` enforcing the project's indentation
settings.
@@ -406,9 +181,6 @@ style conventions are in separate documents:
- `README.md`, `.git`, `.gitignore`, `.editorconfig`
- `LICENSE`, `REPO_POLICIES.md` (copy from the `prompts` repo)
- `Makefile`
- `script/` entrypoints (`bootstrap`, `setup`, `projectname`, `test`,
`lint`, `fmt`, `fmt-check`, `check`, `docker`, `cibuild`, `precommit`,
`install-precommit`)
- `Dockerfile`, `.dockerignore`
- `.gitea/workflows/check.yml`
- Go: `go.mod`, `go.sum`, `.golangci.yml`
TESTING.md
+5 -16
View File
@@ -2,12 +2,8 @@
## DNS Resolution Tests
DNS is never mocked in this project, not in tests and not anywhere
else; see the README section "No DNS mocking. Ever." Every test that
looks something up in DNS **MUST** query live DNS servers, never a
stand-in. Logic that works on record data, such as comparing or
formatting records, may be tested on that data directly with no
lookup.
All resolver tests **MUST** use live queries against real DNS servers.
No mocking of the DNS client layer is permitted.
### Rationale
@@ -21,25 +17,18 @@ real servers ensures the resolver works correctly in production.
- Tests hit real DNS infrastructure and require network access
- Test duration depends on network conditions; timeout tuning keeps
the suite within the 60-second target
the suite within the 30-second target
- Query timeout is calibrated to 3× maximum antipodal RTT (~300ms)
plus processing margin
- Root server fan-out is limited to reduce parallel query load
- Live lookups that expect an answer go through `internal/livednstest`,
which limits how many run at once in a test binary and retries a
lookup that got none
- Flaky failures from transient network issues are acceptable and
should be investigated as potential resolver bugs, not papered over
with mocks or skip flags
### What NOT to do
- **Do not mock, fake or stub DNS** anywhere: no stand-in `DNSClient`,
no stand-in for the watcher's `DNSResolver`, no fake DNS server, no
canned responses
- **Do not mock `DNSClient`** for resolver tests (the mock constructor
exists for unit-testing other packages that consume the resolver)
- **Do not add `-short` flags** to skip slow tests
- **Do not increase `-timeout`** to hide hanging queries
- **Do not remove `-count=1` from `script/test`** — Go's test cache
replays a previous run's output without querying anything, so a
cached pass is not evidence that live resolution works
- **Do not modify linter configuration** to suppress findings
TODO.md
-277
View File
@@ -1,277 +0,0 @@
# Workflow
* branch (from `main`)
* do the work in Next Step
* move Next Step to the top of Completed Steps
* move the top item of Future Steps into Next Step
* commit (`TODO.md` changes in the same commit as the work)
* merge to `main` if the branch is not protected, otherwise open a PR
* push
# Status
pre-1.0. No git tags.
# Next Step
Add the README sections required by policy (Description, Getting Started,
Rationale, Design, TODO, License, Author) if any are still missing.
# Completed Steps
- 2026-09-29: the live-DNS test package is renamed `internal/livednstest` and
added to the `test-support` `deny` list in `.golangci.yml`, so `make lint`
fails when program code imports it (closes #164).
- 2026-09-29: `.golangci.yml` re-fetched unchanged from `sneak/prompts`. It
replaces the deprecated `gomodguard` with `gomodguard_v2`, so `make lint` no
longer warns about it, and turns on `depguard` with the org `test-support`
rule, which rejects `net/http/httptest` except in test files and in files
under a directory whose name ends in `test`. This repo had no `deny` entries
of its own to carry forward (closes #123).
- 2026-09-29: nothing stands in for DNS any more. Watcher tests that look
something up in DNS use the real resolver against live DNS servers and test
record and nameserver changes by preparing the saved state a check starts
from; the resolver timeout test queries an address that never answers, and
`NewFromLoggerWithClient`, used only by its stand-in client, is gone. The
live-DNS retry and concurrency limit moved to `internal/livednstest`, which
both test packages use. `TESTING.md` states the README's rule (closes #159).
- 2026-09-28: the inconsistency alert is sent once, on the check where two
nameservers start to disagree or where a nameserver that disagrees first
appears, instead of on every check while they disagree, and not again after
a restart. Every pair of nameservers is compared, not only neighbours in
sorted order of name (closes #158).
- 2026-09-28: DNS names in record values (CNAME, MX, SRV and NS targets) are
lower-cased, so nameservers that answer in different letter case no longer
count as inconsistent or as a record change (closes #157).
- 2026-09-28: `script/cibuild` and `script/docker` now pass
`--no-cache-filter=lint,builder` so lint and tests run every build (closes
#115).
- 2026-09-28: the server timeout test now drives `Run` and checks the
`http.Server` it serves carries the timeouts; corrected the `ReadTimeout`
note in that test (closes #120).
- 2026-09-28: upaas deploy readiness — runtime image runs as unprivileged
`dnswatcher`, Docker `HEALTHCHECK`, startup fails when the data directory is
not writable, README "Running under upaas" (closes #147).
- 2026-09-21: added behavioural tests for `internal/globals`,
`internal/healthcheck`, and `internal/logger` (closes #110).
- 2026-09-21: `go mod tidy` dropped the redundant `golang.org/x/sync`
`// indirect` line so `script/bootstrap` leaves a clean tree (#132)
- 2026-08-10: comment-only corrections to `script/bootstrap`,
`script/cibuild`, and `Dockerfile.lint`. The `goimports` pin in
`script/bootstrap` was justified by a claim that `script/fmt-check`
runs it on the host; it does not (it runs `gofmt -l .` only), so the
header now credits `script/fmt` alone. `script/cibuild` still claimed
the `Dockerfile` runs `make check`, which stopped being true when
linting moved to its own stage; it now describes the lint stage
(`make fmt-check` plus `golangci-lint`) and the builder stage
(`make test`, `make build`). The `docker`-missing warning in
`script/bootstrap` reads as one sentence instead of three fragments
each re-prefixed with `bootstrap:`. `Dockerfile.lint` now records the
residual risk of omitting `golangci-lint config verify`: unknown
top-level keys in `.golangci.yml` are silently ignored, so a mistyped
key lints clean while applying nothing. No behaviour changed
- 2026-08-10: MIT `LICENSE` added at the repository root, closing the
last gap in `REPO_POLICIES.md`'s required-minimum file list and
removing the all-rights-reserved default that would otherwise have
shipped with a 1.0 tag. The licence choice is the standing org policy
(any public repo lacking a licence gets MIT; a private repo with no
licence is already all-rights-reserved), and this repo is public. The
file holds the canonical MIT text byte-for-byte with only the
copyright line filled in (`Copyright (c) 2026 sneak`); no clauses were
added, removed, or reflowed. `README.md`'s first line now names the
licence, as the Description requirement demands, and the License
section states MIT and points at the file instead of saying the choice
is pending. `make fmt` covers only Go sources (`gofmt -s`,
`goimports`), so it cannot reflow `LICENSE`
- 2026-08-10: the policy scaffold (`REPO_POLICIES.md`, `.editorconfig`,
`.dockerignore`, `.gitea/workflows/check.yml`, and the `fmt-check`,
`docker`, and hooks Makefile targets) is present; it landed piecemeal
across the scripts-to-rule-them-all and policy commits rather than as
the single commit this file once planned
- 2026-08-10: Go's test cache disabled for `script/test` via `-count=1`,
so every invocation actually executes. A cached pass replays an
earlier run's output without querying DNS at all, which in this repo
means the suite's entire premise goes unexercised while the run
reports green in under a second. The conditional verbose rerun that
`REPO_POLICIES.md` mandates was added at the same time (the primary
run had been unconditionally `-v`): quiet first, `-v` only on
failure, `-count=1` on both, and exit 1 forced regardless of the
rerun's result so a flake passing the second time cannot turn the
build green. `-timeout 90s` left alone as the deliberate backstop
above the 60s hard cap. Uncached suite runs ~4s, well inside the 20s
target
- 2026-08-10: live-DNS test flakiness addressed by robustness rather
than gating, per the owner's ruling on #93: new
`internal/resolver/livedns_test.go` adds a package-wide concurrency
gate (so parallel tests stop bursting at the first root server),
retry with exponential backoff on transport failures only, and
quorum instead of unanimity for multi-nameserver assertions. Quorum
tolerates silence only: every per-nameserver status must be in a
closed allowlist (`ok`/`timeout`/`error`, or
`nxdomain`/`timeout`/`error`), so a wrong answer from a minority —
`nodata` today, any status added later — fails the test instead of
sliding through under the majority. The
`make test` cap moved to the new org-wide 60s hard cap / 20s target
with a 90s `-timeout` backstop; `REPO_POLICIES.md` re-vendored
byte-identical from `sneak/prompts`. No mocks, no `-short`, no build
tags, no skips, and no change to production resolver behaviour
- 2026-08-10: all linting moved into Docker: new root `Dockerfile.lint`
on the digest-pinned `golangci/golangci-lint:v2.12.2` image,
`script/lint` reduced to a thin wrapper that builds it with
`--no-cache-filter=lint` so the linter actually executes every run,
golangci-lint install dropped from `script/bootstrap` (goimports
stays, `script/fmt` needs it on the host), and the root `Dockerfile`
given its own lint stage so its build no longer recurses through
`make check` into `script/lint`. `golangci-lint config verify` is
deliberately omitted: it fetches its schema over an unpinned live
HTTPS call
- 2026-08-09: in-flight notification deliveries are now drained at
shutdown (#106): `notify.New` registers an fx `OnStop` hook that waits
on a `sync.WaitGroup` of tracked delivery goroutines, bounded by the
`OnStop` context; on expiry the outstanding count is logged at warn
level and parked retry backoffs are released instead of being dropped
silently, and deliveries submitted after the drain begins are refused
so shutdown cannot be extended indefinitely; an `OnStop` context that
is already expired on entry with nothing outstanding drains quietly
rather than warning about deliveries that were never abandoned
- 2026-08-09: `http.Server` now sets all four socket-level timeouts
(`ReadTimeout` 15s, `ReadHeaderTimeout` 10s, `WriteTimeout` 75s,
`IdleTimeout` 120s) as named constants in `internal/server/server.go`,
closing the slowloris / unreaped-keep-alive exposure required by
`REPO_POLICIES.md` before 1.0; `WriteTimeout` is deliberately greater
than the 60s `chimw.Timeout` handler budget so that budget stays
reachable, and tests in `internal/server` pin both the non-zero
values and that relationship (#99)
- 2026-08-09: security response headers middleware
(`SecurityHeaders()` in `internal/middleware/middleware.go`)
registered globally in `internal/server/routes.go`, so HSTS, CSP,
`X-Frame-Options`, `X-Content-Type-Options`, `Referrer-Policy`, and
`Permissions-Policy` are set on every response including `/s/...` and
`/metrics`; the CSP needs no `unsafe-inline`/`unsafe-eval` because the
dashboard ships no JavaScript and no inline styles; HSTS is emitted
unconditionally per policy (TLS-terminating proxy in front). Remaining
1.0 hardening items — `http.Server` timeouts, request body limits,
rate limiting, CORS scoping — are tracked separately
- 2026-08-07: golangci-lint bumped to v2.12.2 (commit-pinned installs
in `Dockerfile` and `script/bootstrap`); `.golangci.yml` set to the
org-standard v2-schema config used across the org's repos
(owner-authorized; same file is being landed as canonical via prompts
PR #24), with settings under `linters.settings` so the
lll/funlen/cyclop/dupl thresholds apply; fixed the resulting
`goconst`, `dupl`, and `lll` findings; the informational `gomodguard`
deprecation warning under this config is accepted
- 2026-07-07 Adopted scripts-to-rule-them-all: `script/` entrypoints,
Makefile shims, README Entrypoints section
- 2026-02-20: iterative DNS resolver implemented; tests made hermetic
with mocked DNS (origin/feature/resolver, unmerged)
- 2026-02-20: CI actions and go install refs pinned to commit SHAs;
Gitea Actions workflow for make check (origin/ci/make-check, unmerged)
- 2026-02-20: watcher monitoring orchestrator merged to main (#8)
- 2026-02-20: DOMAINS/HOSTNAMES unified into single TARGETS config (#11)
- 2026-02-19: TCP port connectivity checker, made concurrent with port
validation; gosec G704 SSRF findings fixed without suppression
(feature branches, unmerged)
- 2026-02-19: TLS certificate inspector with no-peer-certificates error
path and IP SANs (feature branch, unmerged)
- 2026-02-19: gosec SSRF and formatting fixes on main
- 2026-02-19: initial scaffold with per-nameserver DNS monitoring model
# Future Steps
Compliance:
- Pin Dockerfile base images by sha256 and ensure the Docker build runs
make check
Branch reconciliation:
- Sync local checkout with origin: local main is 8 commits behind
origin/main; local feature/resolver has diverged from
origin/feature/resolver, which already implements the resolver
- Merge in-flight branches to main once green: feature/resolver,
ci/make-check, feature/portcheck-implementation,
feature/tlscheck-implementation
Resolver (plan from untracked TODO.md; largely implemented on
origin/feature/resolver, verify each item before closing):
- Add github.com/miekg/dns dependency
- roots.go: hardcoded IANA root server list (a through m, IPv4/IPv6),
rootServers() returning ip:53 strings
- query.go: low-level query(ctx, server, name, qtype): UDP with TCP
fallback on truncation, RD=0, context respected, 5s per-query timeout,
returns raw *dns.Msg
- trace.go: iterative delegation chasing from roots: referral detection
(NOERROR, empty answer, NS in authority), glue extraction with
bailiwick check, out-of-bailiwick NS resolved with recursion guard,
delegation depth limit (20), retry across nameservers on failure, do
not chase CNAMEs inside trace
- FindAuthoritativeNameservers: NS set via trace, sorted, FQDN
normalized, trailing dot handled; must pass its 9 tests
- QueryNameserver: resolve NS host to IPs, query A/AAAA/CNAME/MX/TXT/
SRV/CAA/NS, build NameserverResponse with status mapping (OK,
NXDomain, NoData, Error), documented record formatting, sorted values,
lame delegation detection; must pass its 16 tests
- QueryAllNameservers: find NS set for parent domain (public suffix
list), query all NS in parallel with bounded concurrency, return map
even when all fail, context cancellation; must pass its 4 tests
- LookupNS: thin wrapper over FindAuthoritativeNameservers, sorted,
identical results; must pass its 3 tests
- ResolveIPAddresses: collect A/AAAA from all NS, follow CNAME chains
with MaxCNAMEDepth, dedupe, sort, NXDOMAIN returns empty slice with
nil error; must pass its 9 tests
- All 39 resolver tests pass, make check green, merge to main
Watcher (internal/watcher/watcher.go):
- Scheduling loop in Run(ctx): initial check on startup, separate
tickers for DNS/port and TLS intervals, persist state via state.Save()
after each cycle, clean shutdown on context cancel
- Domain check: LookupNS, compare to stored state, store silently on
first run, notify with old/new NS lists on change
- Hostname check: QueryAllNameservers, compare per-NS records; notify on
record changes, NS failure, NS recovery, inconsistency detected,
inconsistency resolved, empty response; store silently on first run
- Port check: ResolveIPAddresses, check ports 80 and 443 per IP, notify
on open/closed transitions, handle new and disappeared IPs
- TLS check: for each open IP:443, CheckCertificate; notify on expiry
warning, certificate change (CN/issuer/SANs), TLS failure/recovery
Port checker (internal/portcheck/portcheck.go):
- Tests against known-open ports and RFC documentation IPs
- CheckPort: net.DialTimeout (5s), context respected; (true, nil) open,
(false, nil) closed/timeout/refused, error only for unexpected
failures
TLS checker (internal/tlscheck/tlscheck.go):
- Tests against known public HTTPS servers, verify fields populated
- CheckCertificate: tls.Dial to specific IP:443 with hostname as SNI;
extract subject CN, issuer CN and org, NotAfter, SANs; error on
handshake failure
Notification service (internal/notify/notify.go, Slack/Mattermost/ntfy
backends exist):
- Structured notification types: DNS change, port change, TLS expiry,
TLS change, NS failure, NS recovery, NS inconsistency
- Per-backend formatting: Slack/Mattermost attachment colors (red
failures/expiry, yellow warnings, green recoveries, blue info); ntfy
priorities (urgent failures, high warnings, default changes, low
recoveries); include hostname, nameserver, old/new values, timestamps
HTTP API handlers:
- Wire *state.State and *watcher.Watcher into handler params
- GET /api/v1/status: full state snapshot as JSON
- GET /api/v1/domains: domain states with NS records and last-checked
- GET /api/v1/hostnames: hostname states with per-NS record data
Infrastructure notes (from untracked TODO.md):
- Module path sneak.berlin/go/dnswatcher differs from the git.eeqj.de
remote intentionally; do not "fix" it
- Dependencies: github.com/miekg/dns, golang.org/x/net/publicsuffix
- DNS is never mocked; tests that look something up in DNS query live DNS
servers (README, "No DNS mocking. Ever.")
cmd/dnswatcher/main.go
+4 -2
View File
@@ -25,13 +25,15 @@ import (
//
//nolint:gochecknoglobals // build-time variables
var (
Appname = "dnswatcher"
Version string
Appname = "dnswatcher"
Version string
Buildarch string
)
func main() {
globals.SetAppname(Appname)
globals.SetVersion(Version)
globals.SetBuildarch(Buildarch)
fx.New(
fx.Provide(
go.mod
+1
View File
@@ -40,6 +40,7 @@ require (
go.yaml.in/yaml/v2 v2.4.2 // indirect
go.yaml.in/yaml/v3 v3.0.4 // indirect
golang.org/x/mod v0.32.0 // indirect
golang.org/x/sync v0.19.0 // indirect
golang.org/x/sys v0.41.0 // indirect
golang.org/x/text v0.34.0 // indirect
golang.org/x/tools v0.41.0 // indirect
internal/config/classify_test.go
+5 -25
View File
@@ -17,33 +17,13 @@ func TestClassifyDNSName(t *testing.T) {
}{
{name: "apex domain simple", input: "example.com", want: config.DNSNameTypeDomain},
{name: "hostname simple", input: "www.example.com", want: config.DNSNameTypeHostname},
{
name: "apex domain multi-part TLD",
input: "example.co.uk",
want: config.DNSNameTypeDomain,
},
{
name: "hostname multi-part TLD",
input: "api.example.co.uk",
want: config.DNSNameTypeHostname,
},
{name: "apex domain multi-part TLD", input: "example.co.uk", want: config.DNSNameTypeDomain},
{name: "hostname multi-part TLD", input: "api.example.co.uk", want: config.DNSNameTypeHostname},
{name: "public suffix itself", input: "co.uk", wantErr: true},
{name: "empty string", input: "", wantErr: true},
{
name: "deeply nested hostname",
input: "a.b.c.example.com",
want: config.DNSNameTypeHostname,
},
{
name: "trailing dot stripped",
input: "example.com.",
want: config.DNSNameTypeDomain,
},
{
name: "uppercase normalized",
input: "WWW.Example.COM",
want: config.DNSNameTypeHostname,
},
{name: "deeply nested hostname", input: "a.b.c.example.com", want: config.DNSNameTypeHostname},
{name: "trailing dot stripped", input: "example.com.", want: config.DNSNameTypeDomain},
{name: "uppercase normalized", input: "WWW.Example.COM", want: config.DNSNameTypeHostname},
}
for _, tt := range tests {
internal/config/config.go
+52 -59
View File
@@ -15,6 +15,12 @@ import (
"sneak.berlin/go/dnswatcher/internal/logger"
)
// ErrNoTargets is returned when DNSWATCHER_TARGETS is empty or unset.
var ErrNoTargets = errors.New(
"no targets configured: set DNSWATCHER_TARGETS to a comma-separated " +
"list of DNS names to monitor",
)
// Default configuration values.
const (
defaultPort = 8080
@@ -23,11 +29,6 @@ const (
defaultTLSExpiryWarning = 7
)
// ErrNoTargets is returned when no monitoring targets are configured.
var ErrNoTargets = errors.New(
"no monitoring targets configured: set DNSWATCHER_TARGETS environment variable",
)
// Params contains dependencies for Config.
type Params struct {
fx.In
@@ -38,24 +39,23 @@ type Params struct {
// Config holds application configuration.
type Config struct {
Port int
Debug bool
DataDir string
Domains []string
Hostnames []string
SlackWebhook string
MattermostWebhook string
NtfyTopic string
DNSInterval time.Duration
TLSInterval time.Duration
TLSExpiryWarning int
SentryDSN string
MaintenanceMode bool
MetricsUsername string
MetricsPassword string
SendTestNotification bool
params *Params
log *slog.Logger
Port int
Debug bool
DataDir string
Domains []string
Hostnames []string
SlackWebhook string
MattermostWebhook string
NtfyTopic string
DNSInterval time.Duration
TLSInterval time.Duration
TLSExpiryWarning int
SentryDSN string
MaintenanceMode bool
MetricsUsername string
MetricsPassword string
params *Params
log *slog.Logger
}
// New creates a new Config instance from environment and config files.
@@ -94,7 +94,7 @@ func setupViper(name string) {
viper.SetDefault("PORT", defaultPort)
viper.SetDefault("DEBUG", false)
viper.SetDefault("DATA_DIR", "/var/lib/"+name)
viper.SetDefault("DATA_DIR", "./data")
viper.SetDefault("TARGETS", "")
viper.SetDefault("SLACK_WEBHOOK", "")
viper.SetDefault("MATTERMOST_WEBHOOK", "")
@@ -106,7 +106,6 @@ func setupViper(name string) {
viper.SetDefault("MAINTENANCE_MODE", false)
viper.SetDefault("METRICS_USERNAME", "")
viper.SetDefault("METRICS_PASSWORD", "")
viper.SetDefault("SEND_TEST_NOTIFICATION", false)
}
func buildConfig(
@@ -125,50 +124,35 @@ func buildConfig(
}
}
dnsInterval, err := time.ParseDuration(
viper.GetString("DNS_INTERVAL"),
)
if err != nil {
dnsInterval = defaultDNSInterval
}
tlsInterval, err := time.ParseDuration(
viper.GetString("TLS_INTERVAL"),
)
if err != nil {
tlsInterval = defaultTLSInterval
}
domains, hostnames, err := parseAndValidateTargets()
domains, hostnames, err := classifyAndValidateTargets()
if err != nil {
return nil, err
}
cfg := &Config{
Port: viper.GetInt("PORT"),
Debug: viper.GetBool("DEBUG"),
DataDir: viper.GetString("DATA_DIR"),
Domains: domains,
Hostnames: hostnames,
SlackWebhook: viper.GetString("SLACK_WEBHOOK"),
MattermostWebhook: viper.GetString("MATTERMOST_WEBHOOK"),
NtfyTopic: viper.GetString("NTFY_TOPIC"),
DNSInterval: dnsInterval,
TLSInterval: tlsInterval,
TLSExpiryWarning: viper.GetInt("TLS_EXPIRY_WARNING"),
SentryDSN: viper.GetString("SENTRY_DSN"),
MaintenanceMode: viper.GetBool("MAINTENANCE_MODE"),
MetricsUsername: viper.GetString("METRICS_USERNAME"),
MetricsPassword: viper.GetString("METRICS_PASSWORD"),
SendTestNotification: viper.GetBool("SEND_TEST_NOTIFICATION"),
params: params,
log: log,
Port: viper.GetInt("PORT"),
Debug: viper.GetBool("DEBUG"),
DataDir: viper.GetString("DATA_DIR"),
Domains: domains,
Hostnames: hostnames,
SlackWebhook: viper.GetString("SLACK_WEBHOOK"),
MattermostWebhook: viper.GetString("MATTERMOST_WEBHOOK"),
NtfyTopic: viper.GetString("NTFY_TOPIC"),
DNSInterval: parseDurationOrDefault("DNS_INTERVAL", defaultDNSInterval),
TLSInterval: parseDurationOrDefault("TLS_INTERVAL", defaultTLSInterval),
TLSExpiryWarning: viper.GetInt("TLS_EXPIRY_WARNING"),
SentryDSN: viper.GetString("SENTRY_DSN"),
MaintenanceMode: viper.GetBool("MAINTENANCE_MODE"),
MetricsUsername: viper.GetString("METRICS_USERNAME"),
MetricsPassword: viper.GetString("METRICS_PASSWORD"),
params: params,
log: log,
}
return cfg, nil
}
func parseAndValidateTargets() ([]string, []string, error) {
func classifyAndValidateTargets() ([]string, []string, error) {
domains, hostnames, err := ClassifyTargets(
parseCSV(viper.GetString("TARGETS")),
)
@@ -185,6 +169,15 @@ func parseAndValidateTargets() ([]string, []string, error) {
return domains, hostnames, nil
}
func parseDurationOrDefault(key string, fallback time.Duration) time.Duration {
d, err := time.ParseDuration(viper.GetString(key))
if err != nil {
return fallback
}
return d
}
func parseCSV(input string) []string {
if input == "" {
return nil
internal/config/config_test.go
+62 -237
View File
@@ -1,262 +1,87 @@
package config_test
import (
"errors"
"testing"
"time"
"github.com/spf13/viper"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"go.uber.org/fx"
"sneak.berlin/go/dnswatcher/internal/config"
"sneak.berlin/go/dnswatcher/internal/globals"
"sneak.berlin/go/dnswatcher/internal/logger"
)
// newTestParams creates config.Params suitable for testing
// without requiring the fx dependency injection framework.
func newTestParams(t *testing.T) config.Params {
t.Helper()
g := &globals.Globals{
Appname: "dnswatcher",
Version: "test",
}
l, err := logger.New(nil, logger.Params{Globals: g})
require.NoError(t, err, "failed to create logger")
return config.Params{
Globals: g,
Logger: l,
}
}
// These tests exercise viper global state and MUST NOT use
// t.Parallel(). Each test resets viper for isolation.
func TestNew_DefaultValues(t *testing.T) {
viper.Reset()
t.Setenv("DNSWATCHER_TARGETS", "example.com,www.example.com")
cfg, err := config.New(nil, newTestParams(t))
require.NoError(t, err)
assert.Equal(t, 8080, cfg.Port)
assert.False(t, cfg.Debug)
assert.Equal(t, "/var/lib/dnswatcher", cfg.DataDir)
assert.Equal(t, time.Hour, cfg.DNSInterval)
assert.Equal(t, 12*time.Hour, cfg.TLSInterval)
assert.Equal(t, 7, cfg.TLSExpiryWarning)
assert.False(t, cfg.MaintenanceMode)
assert.Empty(t, cfg.SlackWebhook)
assert.Empty(t, cfg.MattermostWebhook)
assert.Empty(t, cfg.NtfyTopic)
assert.Empty(t, cfg.SentryDSN)
assert.Empty(t, cfg.MetricsUsername)
assert.Empty(t, cfg.MetricsPassword)
assert.False(t, cfg.SendTestNotification)
}
func TestNew_EnvironmentOverrides(t *testing.T) {
viper.Reset()
t.Setenv("DNSWATCHER_TARGETS", "example.com")
t.Setenv("PORT", "9090")
t.Setenv("DNSWATCHER_DEBUG", "true")
t.Setenv("DNSWATCHER_DATA_DIR", "/tmp/test-data")
t.Setenv("DNSWATCHER_DNS_INTERVAL", "30m")
t.Setenv("DNSWATCHER_TLS_INTERVAL", "6h")
t.Setenv("DNSWATCHER_TLS_EXPIRY_WARNING", "14")
t.Setenv("DNSWATCHER_SLACK_WEBHOOK", "https://hooks.slack.com/t")
t.Setenv("DNSWATCHER_MATTERMOST_WEBHOOK", "https://mm.test/hooks/t")
t.Setenv("DNSWATCHER_NTFY_TOPIC", "https://ntfy.sh/test")
t.Setenv("DNSWATCHER_SENTRY_DSN", "https://sentry.test/1")
t.Setenv("DNSWATCHER_MAINTENANCE_MODE", "true")
t.Setenv("DNSWATCHER_METRICS_USERNAME", "admin")
t.Setenv("DNSWATCHER_METRICS_PASSWORD", "secret")
t.Setenv("DNSWATCHER_SEND_TEST_NOTIFICATION", "true")
cfg, err := config.New(nil, newTestParams(t))
require.NoError(t, err)
assert.Equal(t, 9090, cfg.Port)
assert.True(t, cfg.Debug)
assert.Equal(t, "/tmp/test-data", cfg.DataDir)
assert.Equal(t, 30*time.Minute, cfg.DNSInterval)
assert.Equal(t, 6*time.Hour, cfg.TLSInterval)
assert.Equal(t, 14, cfg.TLSExpiryWarning)
assert.Equal(t, "https://hooks.slack.com/t", cfg.SlackWebhook)
assert.Equal(t, "https://mm.test/hooks/t", cfg.MattermostWebhook)
assert.Equal(t, "https://ntfy.sh/test", cfg.NtfyTopic)
assert.Equal(t, "https://sentry.test/1", cfg.SentryDSN)
assert.True(t, cfg.MaintenanceMode)
assert.Equal(t, "admin", cfg.MetricsUsername)
assert.Equal(t, "secret", cfg.MetricsPassword)
assert.True(t, cfg.SendTestNotification)
}
func TestNew_NoTargetsError(t *testing.T) {
viper.Reset()
func TestNewReturnsErrNoTargetsWhenEmpty(t *testing.T) {
// Cannot use t.Parallel() because t.Setenv modifies the process
// environment.
t.Setenv("DNSWATCHER_TARGETS", "")
t.Setenv("DNSWATCHER_DATA_DIR", t.TempDir())
_, err := config.New(nil, newTestParams(t))
require.Error(t, err)
assert.ErrorIs(t, err, config.ErrNoTargets)
}
var cfg *config.Config
func TestNew_OnlyEmptyCSVSegments(t *testing.T) {
viper.Reset()
t.Setenv("DNSWATCHER_TARGETS", " , , ")
_, err := config.New(nil, newTestParams(t))
require.Error(t, err)
assert.ErrorIs(t, err, config.ErrNoTargets)
}
func TestNew_InvalidDNSInterval_FallsBackToDefault(t *testing.T) {
viper.Reset()
t.Setenv("DNSWATCHER_TARGETS", "example.com")
t.Setenv("DNSWATCHER_DNS_INTERVAL", "banana")
cfg, err := config.New(nil, newTestParams(t))
require.NoError(t, err)
assert.Equal(t, time.Hour, cfg.DNSInterval,
"invalid DNS interval should fall back to 1h default")
}
func TestNew_InvalidTLSInterval_FallsBackToDefault(t *testing.T) {
viper.Reset()
t.Setenv("DNSWATCHER_TARGETS", "example.com")
t.Setenv("DNSWATCHER_TLS_INTERVAL", "notaduration")
cfg, err := config.New(nil, newTestParams(t))
require.NoError(t, err)
assert.Equal(t, 12*time.Hour, cfg.TLSInterval,
"invalid TLS interval should fall back to 12h default")
}
func TestNew_BothIntervalsInvalid(t *testing.T) {
viper.Reset()
t.Setenv("DNSWATCHER_TARGETS", "example.com")
t.Setenv("DNSWATCHER_DNS_INTERVAL", "xyz")
t.Setenv("DNSWATCHER_TLS_INTERVAL", "abc")
cfg, err := config.New(nil, newTestParams(t))
require.NoError(t, err)
assert.Equal(t, time.Hour, cfg.DNSInterval)
assert.Equal(t, 12*time.Hour, cfg.TLSInterval)
}
func TestNew_DebugEnablesDebugLogging(t *testing.T) {
viper.Reset()
t.Setenv("DNSWATCHER_TARGETS", "example.com")
t.Setenv("DNSWATCHER_DEBUG", "true")
cfg, err := config.New(nil, newTestParams(t))
require.NoError(t, err)
assert.True(t, cfg.Debug)
}
func TestNew_PortEnvNotPrefixed(t *testing.T) {
viper.Reset()
t.Setenv("DNSWATCHER_TARGETS", "example.com")
t.Setenv("PORT", "3000")
cfg, err := config.New(nil, newTestParams(t))
require.NoError(t, err)
assert.Equal(t, 3000, cfg.Port,
"PORT env should work without DNSWATCHER_ prefix")
}
func TestNew_TargetClassification(t *testing.T) {
viper.Reset()
t.Setenv("DNSWATCHER_TARGETS",
"example.com,www.example.com,api.example.com,example.org")
cfg, err := config.New(nil, newTestParams(t))
require.NoError(t, err)
// example.com and example.org are apex domains
assert.Len(t, cfg.Domains, 2)
// www.example.com and api.example.com are hostnames
assert.Len(t, cfg.Hostnames, 2)
}
func TestNew_InvalidTargetPublicSuffix(t *testing.T) {
viper.Reset()
t.Setenv("DNSWATCHER_TARGETS", "co.uk")
_, err := config.New(nil, newTestParams(t))
require.Error(t, err, "public suffix should be rejected")
}
func TestNew_EmptyAppnameDefaultsToDnswatcher(t *testing.T) {
viper.Reset()
t.Setenv("DNSWATCHER_TARGETS", "example.com")
g := &globals.Globals{Appname: "", Version: "test"}
l, err := logger.New(nil, logger.Params{Globals: g})
require.NoError(t, err)
cfg, err := config.New(
nil, config.Params{Globals: g, Logger: l},
app := fx.New(
fx.Provide(
func() *globals.Globals {
return &globals.Globals{
Appname: "dnswatcher-test-empty",
}
},
logger.New,
config.New,
),
fx.Populate(&cfg),
fx.NopLogger,
)
require.NoError(t, err)
assert.Equal(t, 8080, cfg.Port,
"defaults should load when appname is empty")
err := app.Err()
if err == nil {
t.Fatal(
"expected error when DNSWATCHER_TARGETS is empty, got nil",
)
}
if !errors.Is(err, config.ErrNoTargets) {
t.Errorf("expected ErrNoTargets, got: %v", err)
}
}
func TestNew_TargetsWithWhitespace(t *testing.T) {
viper.Reset()
t.Setenv("DNSWATCHER_TARGETS", " example.com , www.example.com ")
cfg, err := config.New(nil, newTestParams(t))
require.NoError(t, err)
assert.Equal(t, 2, len(cfg.Domains)+len(cfg.Hostnames),
"whitespace around targets should be trimmed")
}
func TestNew_TargetsWithTrailingComma(t *testing.T) {
viper.Reset()
t.Setenv("DNSWATCHER_TARGETS", "example.com,www.example.com,")
cfg, err := config.New(nil, newTestParams(t))
require.NoError(t, err)
assert.Equal(t, 2, len(cfg.Domains)+len(cfg.Hostnames),
"trailing comma should be ignored")
}
func TestNew_CustomDNSIntervalDuration(t *testing.T) {
viper.Reset()
func TestNewSucceedsWithTargets(t *testing.T) {
// Cannot use t.Parallel() because t.Setenv modifies the process
// environment.
t.Setenv("DNSWATCHER_TARGETS", "example.com")
t.Setenv("DNSWATCHER_DNS_INTERVAL", "5s")
t.Setenv("DNSWATCHER_DATA_DIR", t.TempDir())
cfg, err := config.New(nil, newTestParams(t))
require.NoError(t, err)
assert.Equal(t, 5*time.Second, cfg.DNSInterval)
}
// Prevent loading a local config file by changing to a temp dir.
t.Chdir(t.TempDir())
func TestStatePath(t *testing.T) {
t.Parallel()
var cfg *config.Config
tests := []struct {
name string
dataDir string
want string
}{
{"default", "/var/lib/dnswatcher", "/var/lib/dnswatcher/state.json"},
{"absolute", "/var/lib/dw", "/var/lib/dw/state.json"},
{"nested", "/opt/app/data", "/opt/app/data/state.json"},
{"empty", "", "/state.json"},
app := fx.New(
fx.Provide(
func() *globals.Globals {
return &globals.Globals{
Appname: "dnswatcher-test-ok",
}
},
logger.New,
config.New,
),
fx.Populate(&cfg),
fx.NopLogger,
)
err := app.Err()
if err != nil {
t.Fatalf(
"expected no error with valid targets, got: %v",
err,
)
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
cfg := &config.Config{DataDir: tt.dataDir}
assert.Equal(t, tt.want, cfg.StatePath())
})
if len(cfg.Domains) != 1 || cfg.Domains[0] != "example.com" {
t.Errorf(
"expected [example.com], got domains=%v",
cfg.Domains,
)
}
}
internal/config/export_test.go
-6
View File
@@ -1,6 +0,0 @@
package config
// ParseCSVForTest exports parseCSV for use in external tests.
func ParseCSVForTest(input string) []string {
return parseCSV(input)
}
internal/config/parsecsv_test.go
-44
View File
@@ -1,44 +0,0 @@
package config_test
import (
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"sneak.berlin/go/dnswatcher/internal/config"
)
func TestParseCSV(t *testing.T) {
t.Parallel()
tests := []struct {
name string
input string
want []string
}{
{"empty string", "", nil},
{"single value", "a", []string{"a"}},
{"multiple values", "a,b,c", []string{"a", "b", "c"}},
{"whitespace trimmed", " a , b ", []string{"a", "b"}},
{"trailing comma", "a,b,", []string{"a", "b"}},
{"leading comma", ",a,b", []string{"a", "b"}},
{"consecutive commas", "a,,b", []string{"a", "b"}},
{"all empty segments", ",,,", nil},
{"whitespace only", " , , ", nil},
{"tabs", "\ta\t,\tb\t", []string{"a", "b"}},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
got := config.ParseCSVForTest(tt.input)
require.Len(t, got, len(tt.want))
for i, w := range tt.want {
assert.Equal(t, w, got[i])
}
})
}
}
internal/globals/globals.go
+18 -7
View File
@@ -12,15 +12,17 @@ import (
//
//nolint:gochecknoglobals // Required for ldflags injection at build time
var (
mu sync.RWMutex
appname string
version string
mu sync.RWMutex
appname string
version string
buildarch string
)
// Globals holds build-time variables for dependency injection.
type Globals struct {
Appname string
Version string
Appname string
Version string
Buildarch string
}
// New creates a new Globals instance from package-level variables.
@@ -29,8 +31,9 @@ func New(_ fx.Lifecycle) (*Globals, error) {
defer mu.RUnlock()
return &Globals{
Appname: appname,
Version: version,
Appname: appname,
Version: version,
Buildarch: buildarch,
}, nil
}
@@ -49,3 +52,11 @@ func SetVersion(ver string) {
version = ver
}
// SetBuildarch sets the build architecture.
func SetBuildarch(arch string) {
mu.Lock()
defer mu.Unlock()
buildarch = arch
}
internal/globals/globals_test.go
-50
View File
@@ -1,50 +0,0 @@
package globals_test
import (
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"sneak.berlin/go/dnswatcher/internal/globals"
)
// TestGlobals exercises the package-level version and appname
// variables through their setters and read-back via New. These are
// shared package state, so the test mutates a global and must run
// sequentially; it cannot use t.Parallel().
//
//nolint:paralleltest // mutates shared package-level globals, must run sequentially
func TestGlobals(t *testing.T) {
versions := []string{"v1.2.3", "dev", "", "v1.2.3-4-gabcdef"}
for _, want := range versions {
globals.SetVersion(want)
g, err := globals.New(nil)
require.NoError(t, err)
assert.Equal(t, want, g.Version,
"New must surface the version set by SetVersion")
}
names := []string{"dnswatcher", "other", ""}
for _, want := range names {
globals.SetAppname(want)
g, err := globals.New(nil)
require.NoError(t, err)
assert.Equal(t, want, g.Appname,
"New must surface the appname set by SetAppname")
}
// New returns a snapshot: a later SetVersion must not mutate a
// Globals handed out earlier.
globals.SetVersion("first")
g, err := globals.New(nil)
require.NoError(t, err)
globals.SetVersion("second")
assert.Equal(t, "first", g.Version,
"a Globals returned by New must not change when the "+
"package variable is set again")
}
internal/handlers/dashboard.go
-151
View File
@@ -1,151 +0,0 @@
package handlers
import (
"embed"
"fmt"
"html/template"
"math"
"net/http"
"strings"
"time"
"sneak.berlin/go/dnswatcher/internal/notify"
"sneak.berlin/go/dnswatcher/internal/state"
)
//go:embed templates/dashboard.html
var dashboardFS embed.FS
// Time unit constants for relative time calculations.
const (
secondsPerMinute = 60
minutesPerHour = 60
hoursPerDay = 24
)
// newDashboardTemplate parses the embedded dashboard HTML
// template with helper functions.
func newDashboardTemplate() *template.Template {
funcs := template.FuncMap{
"relTime": relTime,
"joinStrings": joinStrings,
"formatRecords": formatRecords,
"expiryDays": expiryDays,
}
return template.Must(
template.New("dashboard.html").
Funcs(funcs).
ParseFS(dashboardFS, "templates/dashboard.html"),
)
}
// dashboardData is the data passed to the dashboard template.
type dashboardData struct {
Snapshot state.Snapshot
Alerts []notify.AlertEntry
StateAge string
GeneratedAt string
}
// HandleDashboard returns the dashboard page handler.
func (h *Handlers) HandleDashboard() http.HandlerFunc {
tmpl := newDashboardTemplate()
return func(
writer http.ResponseWriter,
_ *http.Request,
) {
snap := h.state.GetSnapshot()
alerts := h.notifyHistory.Recent()
data := dashboardData{
Snapshot: snap,
Alerts: alerts,
StateAge: relTime(snap.LastUpdated),
GeneratedAt: time.Now().UTC().Format("2006-01-02 15:04:05"),
}
writer.Header().Set(
"Content-Type", "text/html; charset=utf-8",
)
err := tmpl.Execute(writer, data)
if err != nil {
h.log.Error(
"dashboard template error",
"error", err,
)
}
}
}
// relTime returns a human-readable relative time string such
// as "2 minutes ago" or "never" for zero times.
func relTime(t time.Time) string {
if t.IsZero() {
return "never"
}
d := time.Since(t)
if d < 0 {
return "just now"
}
seconds := int(math.Round(d.Seconds()))
if seconds < secondsPerMinute {
return fmt.Sprintf("%ds ago", seconds)
}
minutes := seconds / secondsPerMinute
if minutes < minutesPerHour {
return fmt.Sprintf("%dm ago", minutes)
}
hours := minutes / minutesPerHour
if hours < hoursPerDay {
return fmt.Sprintf(
"%dh %dm ago", hours, minutes%minutesPerHour,
)
}
days := hours / hoursPerDay
return fmt.Sprintf(
"%dd %dh ago", days, hours%hoursPerDay,
)
}
// joinStrings joins a string slice with a separator.
func joinStrings(items []string, sep string) string {
return strings.Join(items, sep)
}
// formatRecords formats a map of record type → values into a
// compact display string.
func formatRecords(records map[string][]string) string {
if len(records) == 0 {
return "-"
}
var parts []string
for rtype, values := range records {
for _, v := range values {
parts = append(parts, rtype+": "+v)
}
}
return strings.Join(parts, ", ")
}
// expiryDays returns the number of days until the given time,
// rounded down. Returns 0 if already expired.
func expiryDays(t time.Time) int {
d := time.Until(t).Hours() / hoursPerDay
if d < 0 {
return 0
}
return int(d)
}
internal/handlers/dashboard_test.go
-80
View File
@@ -1,80 +0,0 @@
package handlers_test
import (
"testing"
"time"
"sneak.berlin/go/dnswatcher/internal/handlers"
)
func TestRelTime(t *testing.T) {
t.Parallel()
tests := []struct {
name string
dur time.Duration
want string
}{
{"zero", 0, "never"},
{"seconds", 30 * time.Second, "30s ago"},
{"minutes", 5 * time.Minute, "5m ago"},
{"hours", 2*time.Hour + 15*time.Minute, "2h 15m ago"},
{"days", 48*time.Hour + 3*time.Hour, "2d 3h ago"},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
var input time.Time
if tt.dur > 0 {
input = time.Now().Add(-tt.dur)
}
got := handlers.RelTime(input)
if got != tt.want {
t.Errorf(
"RelTime(%v) = %q, want %q",
tt.dur, got, tt.want,
)
}
})
}
}
func TestExpiryDays(t *testing.T) {
t.Parallel()
// 10 days from now.
future := time.Now().Add(10 * 24 * time.Hour)
days := handlers.ExpiryDays(future)
if days < 9 || days > 10 {
t.Errorf("expected ~10 days, got %d", days)
}
// Already expired.
past := time.Now().Add(-24 * time.Hour)
days = handlers.ExpiryDays(past)
if days != 0 {
t.Errorf("expected 0 for expired, got %d", days)
}
}
func TestFormatRecords(t *testing.T) {
t.Parallel()
got := handlers.FormatRecords(nil)
if got != "-" {
t.Errorf("expected -, got %q", got)
}
got = handlers.FormatRecords(map[string][]string{
"A": {"1.2.3.4"},
})
if got != "A: 1.2.3.4" {
t.Errorf("unexpected format: %q", got)
}
}
internal/handlers/export_test.go
-18
View File
@@ -1,18 +0,0 @@
package handlers
import "time"
// RelTime exports relTime for testing.
func RelTime(t time.Time) string {
return relTime(t)
}
// ExpiryDays exports expiryDays for testing.
func ExpiryDays(t time.Time) int {
return expiryDays(t)
}
// FormatRecords exports formatRecords for testing.
func FormatRecords(records map[string][]string) string {
return formatRecords(records)
}
internal/handlers/handlers.go
+8 -16
View File
@@ -11,8 +11,6 @@ import (
"sneak.berlin/go/dnswatcher/internal/globals"
"sneak.berlin/go/dnswatcher/internal/healthcheck"
"sneak.berlin/go/dnswatcher/internal/logger"
"sneak.berlin/go/dnswatcher/internal/notify"
"sneak.berlin/go/dnswatcher/internal/state"
)
// Params contains dependencies for Handlers.
@@ -22,29 +20,23 @@ type Params struct {
Logger *logger.Logger
Globals *globals.Globals
Healthcheck *healthcheck.Healthcheck
State *state.State
Notify *notify.Service
}
// Handlers provides HTTP request handlers.
type Handlers struct {
log *slog.Logger
params *Params
globals *globals.Globals
hc *healthcheck.Healthcheck
state *state.State
notifyHistory *notify.AlertHistory
log *slog.Logger
params *Params
globals *globals.Globals
hc *healthcheck.Healthcheck
}
// New creates a new Handlers instance.
func New(_ fx.Lifecycle, params Params) (*Handlers, error) {
return &Handlers{
log: params.Logger.Get(),
params: &params,
globals: params.Globals,
hc: params.Healthcheck,
state: params.State,
notifyHistory: params.Notify.History(),
log: params.Logger.Get(),
params: &params,
globals: params.Globals,
hc: params.Healthcheck,
}, nil
}
internal/handlers/status.go
+5 -200
View File
@@ -2,217 +2,22 @@ package handlers
import (
"net/http"
"sort"
"time"
"sneak.berlin/go/dnswatcher/internal/state"
)
// statusDomainInfo holds status information for a monitored domain.
type statusDomainInfo struct {
Nameservers []string `json:"nameservers"`
LastChecked time.Time `json:"lastChecked"`
}
// statusHostnameNSInfo holds per-nameserver status for a hostname.
type statusHostnameNSInfo struct {
Records map[string][]string `json:"records"`
Status string `json:"status"`
LastChecked time.Time `json:"lastChecked"`
}
// statusHostnameInfo holds status information for a monitored hostname.
type statusHostnameInfo struct {
Nameservers map[string]*statusHostnameNSInfo `json:"nameservers"`
LastChecked time.Time `json:"lastChecked"`
}
// statusPortInfo holds status information for a monitored port.
type statusPortInfo struct {
Open bool `json:"open"`
Hostnames []string `json:"hostnames"`
LastChecked time.Time `json:"lastChecked"`
}
// statusCertificateInfo holds status information for a TLS certificate.
type statusCertificateInfo struct {
CommonName string `json:"commonName"`
Issuer string `json:"issuer"`
NotAfter time.Time `json:"notAfter"`
SubjectAlternativeNames []string `json:"subjectAlternativeNames"`
Status string `json:"status"`
LastChecked time.Time `json:"lastChecked"`
}
// statusCounts holds summary counts of monitored resources.
type statusCounts struct {
Domains int `json:"domains"`
Hostnames int `json:"hostnames"`
Ports int `json:"ports"`
PortsOpen int `json:"portsOpen"`
Certificates int `json:"certificates"`
CertsOK int `json:"certificatesOk"`
CertsError int `json:"certificatesError"`
}
// statusResponse is the full /api/v1/status response.
type statusResponse struct {
Status string `json:"status"`
LastUpdated time.Time `json:"lastUpdated"`
Counts statusCounts `json:"counts"`
Domains map[string]*statusDomainInfo `json:"domains"`
Hostnames map[string]*statusHostnameInfo `json:"hostnames"`
Ports map[string]*statusPortInfo `json:"ports"`
Certificates map[string]*statusCertificateInfo `json:"certificates"`
}
// HandleStatus returns the monitoring status handler.
func (h *Handlers) HandleStatus() http.HandlerFunc {
type response struct {
Status string `json:"status"`
}
return func(
writer http.ResponseWriter,
request *http.Request,
) {
snap := h.state.GetSnapshot()
resp := buildStatusResponse(snap)
h.respondJSON(
writer, request,
resp,
&response{Status: "ok"},
http.StatusOK,
)
}
}
// buildStatusResponse constructs the full status response from
// the current monitoring snapshot.
func buildStatusResponse(
snap state.Snapshot,
) *statusResponse {
resp := &statusResponse{
Status: "ok",
LastUpdated: snap.LastUpdated,
Domains: make(map[string]*statusDomainInfo),
Hostnames: make(map[string]*statusHostnameInfo),
Ports: make(map[string]*statusPortInfo),
Certificates: make(map[string]*statusCertificateInfo),
}
buildDomains(snap, resp)
buildHostnames(snap, resp)
buildPorts(snap, resp)
buildCertificates(snap, resp)
buildCounts(resp)
return resp
}
func buildDomains(
snap state.Snapshot,
resp *statusResponse,
) {
for name, ds := range snap.Domains {
ns := make([]string, len(ds.Nameservers))
copy(ns, ds.Nameservers)
sort.Strings(ns)
resp.Domains[name] = &statusDomainInfo{
Nameservers: ns,
LastChecked: ds.LastChecked,
}
}
}
func buildHostnames(
snap state.Snapshot,
resp *statusResponse,
) {
for name, hs := range snap.Hostnames {
info := &statusHostnameInfo{
Nameservers: make(map[string]*statusHostnameNSInfo),
LastChecked: hs.LastChecked,
}
for ns, nsState := range hs.RecordsByNameserver {
recs := make(map[string][]string, len(nsState.Records))
for rtype, vals := range nsState.Records {
copied := make([]string, len(vals))
copy(copied, vals)
recs[rtype] = copied
}
info.Nameservers[ns] = &statusHostnameNSInfo{
Records: recs,
Status: nsState.Status,
LastChecked: nsState.LastChecked,
}
}
resp.Hostnames[name] = info
}
}
func buildPorts(
snap state.Snapshot,
resp *statusResponse,
) {
for key, ps := range snap.Ports {
hostnames := make([]string, len(ps.Hostnames))
copy(hostnames, ps.Hostnames)
sort.Strings(hostnames)
resp.Ports[key] = &statusPortInfo{
Open: ps.Open,
Hostnames: hostnames,
LastChecked: ps.LastChecked,
}
}
}
func buildCertificates(
snap state.Snapshot,
resp *statusResponse,
) {
for key, cs := range snap.Certificates {
sans := make([]string, len(cs.SubjectAlternativeNames))
copy(sans, cs.SubjectAlternativeNames)
resp.Certificates[key] = &statusCertificateInfo{
CommonName: cs.CommonName,
Issuer: cs.Issuer,
NotAfter: cs.NotAfter,
SubjectAlternativeNames: sans,
Status: cs.Status,
LastChecked: cs.LastChecked,
}
}
}
func buildCounts(resp *statusResponse) {
var portsOpen, certsOK, certsError int
for _, ps := range resp.Ports {
if ps.Open {
portsOpen++
}
}
for _, cs := range resp.Certificates {
switch cs.Status {
case "ok":
certsOK++
case "error":
certsError++
}
}
resp.Counts = statusCounts{
Domains: len(resp.Domains),
Hostnames: len(resp.Hostnames),
Ports: len(resp.Ports),
PortsOpen: portsOpen,
Certificates: len(resp.Certificates),
CertsOK: certsOK,
CertsError: certsError,
}
}
internal/handlers/templates/dashboard.html
-370
View File
@@ -1,370 +0,0 @@
<!doctype html>
<html lang="en" class="bg-slate-950">
<head>
<meta charset="utf-8" />
<meta http-equiv="refresh" content="30" />
<meta name="viewport" content="width=device-width, initial-scale=1" />
<title>dnswatcher</title>
<link rel="stylesheet" href="/s/css/tailwind.min.css" />
</head>
<body
class="bg-surface-950 text-slate-300 font-mono text-sm min-h-screen antialiased"
>
<div class="max-w-6xl mx-auto px-4 py-8">
{{/* ---- Header ---- */}}
<div class="mb-8">
<h1 class="text-2xl font-bold text-teal-400 tracking-tight">
dnswatcher
</h1>
<p class="text-xs text-slate-500 mt-1">
state updated {{ .StateAge }} &middot; page generated
{{ .GeneratedAt }} UTC &middot; auto-refresh 30s
</p>
</div>
{{/* ---- Summary bar ---- */}}
<div
class="grid grid-cols-2 sm:grid-cols-4 gap-3 mb-8"
>
<div class="bg-surface-800 border border-slate-700/50 rounded-lg p-4">
<div class="text-xs text-slate-500 uppercase tracking-wider">
Domains
</div>
<div class="text-2xl font-bold text-teal-400 mt-1">
{{ len .Snapshot.Domains }}
</div>
</div>
<div class="bg-surface-800 border border-slate-700/50 rounded-lg p-4">
<div class="text-xs text-slate-500 uppercase tracking-wider">
Hostnames
</div>
<div class="text-2xl font-bold text-teal-400 mt-1">
{{ len .Snapshot.Hostnames }}
</div>
</div>
<div class="bg-surface-800 border border-slate-700/50 rounded-lg p-4">
<div class="text-xs text-slate-500 uppercase tracking-wider">
Ports
</div>
<div class="text-2xl font-bold text-teal-400 mt-1">
{{ len .Snapshot.Ports }}
</div>
</div>
<div class="bg-surface-800 border border-slate-700/50 rounded-lg p-4">
<div class="text-xs text-slate-500 uppercase tracking-wider">
Certificates
</div>
<div class="text-2xl font-bold text-teal-400 mt-1">
{{ len .Snapshot.Certificates }}
</div>
</div>
</div>
{{/* ---- Domains ---- */}}
<section class="mb-8">
<h2
class="text-sm font-semibold text-teal-300 uppercase tracking-wider mb-3 border-b border-slate-700/50 pb-2"
>
Domains
</h2>
{{ if .Snapshot.Domains }}
<div class="overflow-x-auto">
<table class="w-full text-left text-xs">
<thead>
<tr class="text-slate-500 uppercase tracking-wider">
<th class="py-2 px-3">Domain</th>
<th class="py-2 px-3">Nameservers</th>
<th class="py-2 px-3">Checked</th>
</tr>
</thead>
<tbody class="divide-y divide-slate-800">
{{ range $name, $ds := .Snapshot.Domains }}
<tr class="hover:bg-surface-800/50">
<td class="py-2 px-3 text-slate-200 font-medium">
{{ $name }}
</td>
<td class="py-2 px-3 text-slate-400 break-all">
{{ joinStrings $ds.Nameservers ", " }}
</td>
<td class="py-2 px-3 text-slate-500 whitespace-nowrap">
{{ relTime $ds.LastChecked }}
</td>
</tr>
{{ end }}
</tbody>
</table>
</div>
{{ else }}
<p class="text-slate-600 italic text-xs">
No domains configured.
</p>
{{ end }}
</section>
{{/* ---- Hostnames ---- */}}
<section class="mb-8">
<h2
class="text-sm font-semibold text-teal-300 uppercase tracking-wider mb-3 border-b border-slate-700/50 pb-2"
>
Hostnames
</h2>
{{ if .Snapshot.Hostnames }}
<div class="overflow-x-auto">
<table class="w-full text-left text-xs">
<thead>
<tr class="text-slate-500 uppercase tracking-wider">
<th class="py-2 px-3">Hostname</th>
<th class="py-2 px-3">NS</th>
<th class="py-2 px-3">Status</th>
<th class="py-2 px-3">Records</th>
<th class="py-2 px-3">Checked</th>
</tr>
</thead>
<tbody class="divide-y divide-slate-800">
{{ range $name, $hs := .Snapshot.Hostnames }}
{{ range $ns, $nsr := $hs.RecordsByNameserver }}
<tr class="hover:bg-surface-800/50">
<td class="py-2 px-3 text-slate-200 font-medium">
{{ $name }}
</td>
<td class="py-2 px-3 text-slate-400 break-all">
{{ $ns }}
</td>
<td class="py-2 px-3">
{{ if eq $nsr.Status "ok" }}
<span
class="inline-block px-1.5 py-0.5 rounded text-[10px] font-bold uppercase bg-teal-900/50 text-teal-400 border border-teal-700/30"
>ok</span
>
{{ else }}
<span
class="inline-block px-1.5 py-0.5 rounded text-[10px] font-bold uppercase bg-red-900/50 text-red-400 border border-red-700/30"
>{{ $nsr.Status }}</span
>
{{ end }}
</td>
<td
class="py-2 px-3 text-slate-400 break-all max-w-xs"
>
{{ formatRecords $nsr.Records }}
</td>
<td class="py-2 px-3 text-slate-500 whitespace-nowrap">
{{ relTime $nsr.LastChecked }}
</td>
</tr>
{{ end }}
{{ end }}
</tbody>
</table>
</div>
{{ else }}
<p class="text-slate-600 italic text-xs">
No hostnames configured.
</p>
{{ end }}
</section>
{{/* ---- Ports ---- */}}
<section class="mb-8">
<h2
class="text-sm font-semibold text-teal-300 uppercase tracking-wider mb-3 border-b border-slate-700/50 pb-2"
>
Ports
</h2>
{{ if .Snapshot.Ports }}
<div class="overflow-x-auto">
<table class="w-full text-left text-xs">
<thead>
<tr class="text-slate-500 uppercase tracking-wider">
<th class="py-2 px-3">Address</th>
<th class="py-2 px-3">State</th>
<th class="py-2 px-3">Hostnames</th>
<th class="py-2 px-3">Checked</th>
</tr>
</thead>
<tbody class="divide-y divide-slate-800">
{{ range $key, $ps := .Snapshot.Ports }}
<tr class="hover:bg-surface-800/50">
<td class="py-2 px-3 text-slate-200 font-medium">
{{ $key }}
</td>
<td class="py-2 px-3">
{{ if $ps.Open }}
<span
class="inline-block px-1.5 py-0.5 rounded text-[10px] font-bold uppercase bg-teal-900/50 text-teal-400 border border-teal-700/30"
>open</span
>
{{ else }}
<span
class="inline-block px-1.5 py-0.5 rounded text-[10px] font-bold uppercase bg-red-900/50 text-red-400 border border-red-700/30"
>closed</span
>
{{ end }}
</td>
<td class="py-2 px-3 text-slate-400 break-all">
{{ joinStrings $ps.Hostnames ", " }}
</td>
<td class="py-2 px-3 text-slate-500 whitespace-nowrap">
{{ relTime $ps.LastChecked }}
</td>
</tr>
{{ end }}
</tbody>
</table>
</div>
{{ else }}
<p class="text-slate-600 italic text-xs">
No port data yet.
</p>
{{ end }}
</section>
{{/* ---- Certificates ---- */}}
<section class="mb-8">
<h2
class="text-sm font-semibold text-teal-300 uppercase tracking-wider mb-3 border-b border-slate-700/50 pb-2"
>
Certificates
</h2>
{{ if .Snapshot.Certificates }}
<div class="overflow-x-auto">
<table class="w-full text-left text-xs">
<thead>
<tr class="text-slate-500 uppercase tracking-wider">
<th class="py-2 px-3">Endpoint</th>
<th class="py-2 px-3">Status</th>
<th class="py-2 px-3">CN</th>
<th class="py-2 px-3">Issuer</th>
<th class="py-2 px-3">Expires</th>
<th class="py-2 px-3">Checked</th>
</tr>
</thead>
<tbody class="divide-y divide-slate-800">
{{ range $key, $cs := .Snapshot.Certificates }}
<tr class="hover:bg-surface-800/50">
<td class="py-2 px-3 text-slate-400 break-all">
{{ $key }}
</td>
<td class="py-2 px-3">
{{ if eq $cs.Status "ok" }}
<span
class="inline-block px-1.5 py-0.5 rounded text-[10px] font-bold uppercase bg-teal-900/50 text-teal-400 border border-teal-700/30"
>ok</span
>
{{ else }}
<span
class="inline-block px-1.5 py-0.5 rounded text-[10px] font-bold uppercase bg-red-900/50 text-red-400 border border-red-700/30"
>{{ $cs.Status }}</span
>
{{ end }}
</td>
<td class="py-2 px-3 text-slate-200">
{{ $cs.CommonName }}
</td>
<td class="py-2 px-3 text-slate-400 break-all">
{{ $cs.Issuer }}
</td>
<td class="py-2 px-3 whitespace-nowrap">
{{ if not $cs.NotAfter.IsZero }}
{{ $days := expiryDays $cs.NotAfter }}
{{ if lt $days 7 }}
<span class="text-red-400 font-medium"
>{{ $cs.NotAfter.Format "2006-01-02" }}
({{ $days }}d)</span
>
{{ else if lt $days 30 }}
<span class="text-amber-400"
>{{ $cs.NotAfter.Format "2006-01-02" }}
({{ $days }}d)</span
>
{{ else }}
<span class="text-slate-400"
>{{ $cs.NotAfter.Format "2006-01-02" }}
({{ $days }}d)</span
>
{{ end }}
{{ end }}
</td>
<td class="py-2 px-3 text-slate-500 whitespace-nowrap">
{{ relTime $cs.LastChecked }}
</td>
</tr>
{{ end }}
</tbody>
</table>
</div>
{{ else }}
<p class="text-slate-600 italic text-xs">
No certificate data yet.
</p>
{{ end }}
</section>
{{/* ---- Recent Alerts ---- */}}
<section class="mb-8">
<h2
class="text-sm font-semibold text-teal-300 uppercase tracking-wider mb-3 border-b border-slate-700/50 pb-2"
>
Recent Alerts ({{ len .Alerts }})
</h2>
{{ if .Alerts }}
<div class="space-y-2">
{{ range .Alerts }}
<div
class="bg-surface-800 border rounded-lg px-4 py-3 {{ if eq .Priority "error" }}border-red-700/40{{ else if eq .Priority "warning" }}border-amber-700/40{{ else if eq .Priority "success" }}border-teal-700/40{{ else }}border-blue-700/40{{ end }}"
>
<div class="flex items-center gap-3 mb-1">
{{ if eq .Priority "error" }}
<span
class="inline-block px-1.5 py-0.5 rounded text-[10px] font-bold uppercase bg-red-900/50 text-red-400 border border-red-700/30"
>error</span
>
{{ else if eq .Priority "warning" }}
<span
class="inline-block px-1.5 py-0.5 rounded text-[10px] font-bold uppercase bg-amber-900/50 text-amber-400 border border-amber-700/30"
>warning</span
>
{{ else if eq .Priority "success" }}
<span
class="inline-block px-1.5 py-0.5 rounded text-[10px] font-bold uppercase bg-teal-900/50 text-teal-400 border border-teal-700/30"
>success</span
>
{{ else }}
<span
class="inline-block px-1.5 py-0.5 rounded text-[10px] font-bold uppercase bg-blue-900/50 text-blue-400 border border-blue-700/30"
>info</span
>
{{ end }}
<span class="text-slate-200 text-xs font-medium">
{{ .Title }}
</span>
<span class="text-slate-600 text-[11px] ml-auto whitespace-nowrap">
{{ .Timestamp.Format "2006-01-02 15:04:05" }} UTC
({{ relTime .Timestamp }})
</span>
</div>
<p
class="text-slate-400 text-xs whitespace-pre-line pl-0.5"
>
{{ .Message }}
</p>
</div>
{{ end }}
</div>
{{ else }}
<p class="text-slate-600 italic text-xs">
No alerts recorded since last restart.
</p>
{{ end }}
</section>
{{/* ---- Footer ---- */}}
<div
class="text-[11px] text-slate-700 border-t border-slate-800 pt-4 mt-8"
>
dnswatcher &middot; monitoring {{ len .Snapshot.Domains }} domains +
{{ len .Snapshot.Hostnames }} hostnames
</div>
</div>
</body>
</html>
internal/healthcheck/healthcheck_test.go
-134
View File
@@ -1,134 +0,0 @@
package healthcheck_test
import (
"context"
"encoding/json"
"testing"
"time"
"go.uber.org/fx"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"sneak.berlin/go/dnswatcher/internal/config"
"sneak.berlin/go/dnswatcher/internal/globals"
"sneak.berlin/go/dnswatcher/internal/healthcheck"
"sneak.berlin/go/dnswatcher/internal/logger"
)
// recordingLifecycle is a minimal fx.Lifecycle that records the hooks
// appended to it, so healthcheck.New can be exercised through its real
// constructor without standing up a whole fx application.
type recordingLifecycle struct {
hooks []fx.Hook
}
func (l *recordingLifecycle) Append(hook fx.Hook) {
l.hooks = append(l.hooks, hook)
}
// newHealthcheck builds a Healthcheck through the real constructor and
// runs the registered OnStart hook so StartupTime is set the same way
// the fx lifecycle would set it.
func newHealthcheck(
t *testing.T,
maintenance bool,
version string,
) *healthcheck.Healthcheck {
t.Helper()
g := &globals.Globals{Appname: "dnswatcher", Version: version}
log, err := logger.New(nil, logger.Params{Globals: g})
require.NoError(t, err)
lifecycle := &recordingLifecycle{}
hc, err := healthcheck.New(lifecycle, healthcheck.Params{
Globals: g,
Config: &config.Config{MaintenanceMode: maintenance},
Logger: log,
})
require.NoError(t, err)
require.Len(t, lifecycle.hooks, 1,
"New must register exactly one lifecycle hook")
require.NotNil(t, lifecycle.hooks[0].OnStart)
require.NoError(t, lifecycle.hooks[0].OnStart(context.Background()))
return hc
}
func TestCheckStatusAndPayloadShape(t *testing.T) {
t.Parallel()
hc := newHealthcheck(t, false, "v9.9.9")
resp := hc.Check()
assert.Equal(t, "ok", resp.Status)
// The JSON shape and field names are part of the contract for the
// /health and /.well-known/healthcheck routes, so assert on the
// exact set of keys the response marshals to.
raw, err := json.Marshal(resp)
require.NoError(t, err)
var fields map[string]json.RawMessage
require.NoError(t, json.Unmarshal(raw, &fields))
wantKeys := []string{
"status",
"now",
"uptimeSeconds",
"uptimeHuman",
"version",
"appname",
"maintenanceMode",
}
assert.Len(t, fields, len(wantKeys),
"response must marshal to exactly the documented fields")
for _, key := range wantKeys {
assert.Contains(t, fields, key, "missing JSON field %q", key)
}
// The Now field is documented as RFC3339Nano; a change to the
// format constant should turn this red.
_, err = time.Parse(time.RFC3339Nano, resp.Now)
assert.NoError(t, err, "Now must be RFC3339Nano")
}
func TestCheckMaintenanceModeReflectsConfig(t *testing.T) {
t.Parallel()
tests := []struct {
name string
maintenance bool
}{
{"maintenance off", false},
{"maintenance on", true},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
hc := newHealthcheck(t, tt.maintenance, "test")
resp := hc.Check()
assert.Equal(t, tt.maintenance, resp.Maintenance,
"maintenanceMode must mirror Config.MaintenanceMode")
})
}
}
func TestCheckSurfacesVersionAndAppname(t *testing.T) {
t.Parallel()
hc := newHealthcheck(t, false, "surfaced-version-123")
resp := hc.Check()
assert.Equal(t, "surfaced-version-123", resp.Version,
"version from globals must appear in the payload")
assert.Equal(t, "dnswatcher", resp.Appname)
}
internal/livednstest/livednstest.go
-121
View File
@@ -1,121 +0,0 @@
// Package livednstest runs the live DNS operations of tests. Tests that
// look something up in DNS query live DNS servers, never a stand-in —
// see TESTING.md. Nothing here mocks, fakes, stubs, records or replays
// DNS, and nothing here skips a test: it only changes *how* the live
// queries are issued, so that a single dropped UDP packet or one slow
// authoritative server does not turn correct code into a red build.
//
// Two mechanisms:
//
// 1. Bounded concurrency. Tests run in parallel and the build hosts
// have many cores, so without a limit every test starts its own
// iterative resolution at the same instant and they all hit the
// first root server within a few milliseconds of each other. Root
// servers rate-limit that, which shows up as a different arbitrary
// subset of tests failing on each run. Run caps how many live
// operations are in flight at once in one test binary.
//
// 2. Retry with exponential backoff. Each live operation gets several
// attempts with its own timeout. An attempt is retried when it
// obtained nothing to check, never because of what the test
// asserts about the result, so a wrong result still fails on the
// first attempt. A fault in the code under test that leaves
// nothing to check looks the same as live DNS not answering, and
// fails only after the last attempt.
package livednstest
import (
"context"
"errors"
"testing"
"time"
)
const (
// attempts is how many times a live DNS operation is attempted
// before the test fails.
attempts = 3
// AttemptTimeout bounds one attempt. Worst case for an operation
// is attempts * AttemptTimeout plus the backoff — about 26
// seconds, well inside the 90-second `go test -timeout` backstop
// even when several operations exhaust their attempts.
AttemptTimeout = 8 * time.Second
// backoffBase is the delay after the first failed attempt; it is
// multiplied by backoffFactor each time.
backoffBase = 500 * time.Millisecond
// backoffFactor is the exponential backoff multiplier.
backoffFactor = 2
// Concurrency caps how many live operations may be in flight
// across one test binary at once.
Concurrency = 6
)
// gate bounds concurrent live operations. It has to be package scoped:
// the whole point is that it is shared by every parallel test in the
// test binary.
//
//nolint:gochecknoglobals // package-wide live query rate limit
var gate = make(chan struct{}, Concurrency)
// ErrNoAnswer reports that a live operation produced no usable answer,
// which is retried rather than asserted on.
var ErrNoAnswer = errors.New("no answer from live DNS")
// Run executes one attempt of a live operation, holding a slot in gate
// for its duration and bounding it with its own timeout.
func Run(op func(ctx context.Context) error) error {
gate <- struct{}{}
defer func() { <-gate }()
ctx, cancel := context.WithTimeout(
context.Background(), AttemptTimeout,
)
defer cancel()
return op(ctx)
}
// Retry runs op until it reports success, retrying failures with
// exponential backoff, and fails the test if every attempt fails. op
// returns an error only for a failure to obtain an answer — never for
// an answer the test disagrees with, which belongs in an assertion so
// that it fails immediately. op stores whatever it obtained where its
// caller can find it.
func Retry(
t *testing.T,
what string,
op func(ctx context.Context) error,
) {
t.Helper()
var last error
backoff := backoffBase
for attempt := range attempts {
if attempt > 0 {
t.Logf(
"%s: attempt %d of %d failed (%v), "+
"retrying in %s",
what, attempt, attempts, last, backoff,
)
time.Sleep(backoff)
backoff *= backoffFactor
}
last = Run(op)
if last == nil {
return
}
}
t.Fatalf(
"%s: all %d live attempts failed: %v",
what, attempts, last,
)
}
internal/livednstest/livednstest_test.go
-103
View File
@@ -1,103 +0,0 @@
package livednstest_test
import (
"context"
"sync"
"testing"
"time"
"github.com/stretchr/testify/assert"
"sneak.berlin/go/dnswatcher/internal/livednstest"
)
// Tests for the retry and the concurrency limit themselves. They
// perform no DNS resolution of any kind.
func TestRetryRecoversFromTransientFailure(t *testing.T) {
t.Parallel()
const wantAttempts = 2
attempts := 0
livednstest.Retry(t, "transient", func(_ context.Context) error {
attempts++
if attempts < wantAttempts {
return livednstest.ErrNoAnswer
}
return nil
})
assert.Equal(t, wantAttempts, attempts)
}
func TestRetryGivesEachAttemptADeadline(t *testing.T) {
t.Parallel()
livednstest.Retry(t, "deadline", func(ctx context.Context) error {
deadline, ok := ctx.Deadline()
assert.True(t, ok, "attempt should carry a deadline")
remaining := time.Until(deadline)
assert.LessOrEqual(t, remaining, livednstest.AttemptTimeout)
// Lower bound too: without one this passes for a
// deadline far shorter than intended, which would
// silently turn every live attempt into an instant
// timeout.
assert.Greater(t, remaining, livednstest.AttemptTimeout/2)
return nil
})
}
func TestRunBoundsConcurrency(t *testing.T) {
t.Parallel()
const workers = 24
var (
mu sync.Mutex
wg sync.WaitGroup
inFlight int
maxSeen int
)
wg.Add(workers)
for range workers {
go func() {
defer wg.Done()
_ = livednstest.Run(func(_ context.Context) error {
mu.Lock()
inFlight++
if inFlight > maxSeen {
maxSeen = inFlight
}
mu.Unlock()
time.Sleep(time.Millisecond)
mu.Lock()
inFlight--
mu.Unlock()
return nil
})
}()
}
wg.Wait()
assert.Positive(t, maxSeen)
assert.LessOrEqual(
t, maxSeen, livednstest.Concurrency,
"live queries must stay under the package-wide gate",
)
}
internal/logger/logger.go
+1
View File
@@ -78,5 +78,6 @@ func (l *Logger) Identify() {
l.log.Info("starting",
"appname", l.params.Globals.Appname,
"version", l.params.Globals.Version,
"buildarch", l.params.Globals.Buildarch,
)
}
internal/logger/logger_test.go
-66
View File
@@ -1,66 +0,0 @@
package logger_test
import (
"context"
"log/slog"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"sneak.berlin/go/dnswatcher/internal/globals"
"sneak.berlin/go/dnswatcher/internal/logger"
)
func newTestLogger(t *testing.T) *logger.Logger {
t.Helper()
g := &globals.Globals{Appname: "dnswatcher", Version: "test"}
l, err := logger.New(nil, logger.Params{Globals: g})
require.NoError(t, err)
return l
}
// TestNewReturnsUsableLogger checks that the constructor yields a
// working *slog.Logger.
func TestNewReturnsUsableLogger(t *testing.T) {
t.Parallel()
l := newTestLogger(t)
require.NotNil(t, l.Get(), "Get must return a non-nil logger")
}
// TestDefaultLevelExcludesDebug verifies the default configuration
// logs at info: debug records are suppressed, info records pass.
func TestDefaultLevelExcludesDebug(t *testing.T) {
t.Parallel()
log := newTestLogger(t).Get()
ctx := context.Background()
assert.False(t, log.Enabled(ctx, slog.LevelDebug),
"debug must be suppressed at the default level")
assert.True(t, log.Enabled(ctx, slog.LevelInfo),
"info must be enabled at the default level")
}
// TestEnableDebugLoggingChangesLevel verifies the debug and non-debug
// configurations differ as intended: enabling debug makes debug
// records pass where they previously did not.
func TestEnableDebugLoggingChangesLevel(t *testing.T) {
t.Parallel()
l := newTestLogger(t)
log := l.Get()
ctx := context.Background()
require.False(t, log.Enabled(ctx, slog.LevelDebug),
"debug must start disabled")
l.EnableDebugLogging()
assert.True(t, log.Enabled(ctx, slog.LevelDebug),
"debug must be enabled after EnableDebugLogging")
}
internal/middleware/middleware.go
-85
View File
@@ -21,60 +21,6 @@ import (
// corsMaxAge is the maximum age for CORS preflight responses.
const corsMaxAge = 300
// Security response header values applied to every response.
//
// The CSP is as strict as the dashboard allows: the template ships no
// JavaScript, no inline styles, no inline event handlers and no images,
// and its only subresource is the embedded stylesheet at
// /s/css/tailwind.min.css, which style-src 'self' permits. Neither
// unsafe-inline nor unsafe-eval is used. frame-ancestors 'none' is the
// primary anti-framing control; X-Frame-Options is the legacy fallback.
const (
// hstsValue is emitted unconditionally, including over plain HTTP,
// because the service runs behind a TLS-terminating proxy and the
// browser must still enforce HTTPS end to end.
hstsValue = "max-age=31536000; includeSubDomains"
cspValue = "default-src 'self'; " +
"script-src 'none'; " +
"style-src 'self'; " +
"img-src 'self'; " +
"font-src 'none'; " +
"connect-src 'none'; " +
"object-src 'none'; " +
"base-uri 'none'; " +
"form-action 'none'; " +
"frame-ancestors 'none'"
frameOptionsValue = "DENY"
contentTypeOptionsValue = "nosniff"
// referrerPolicyValue is stricter than the policy minimum of
// strict-origin-when-cross-origin: the dashboard has no
// cross-origin navigation needs and its URL may name internal
// hosts.
referrerPolicyValue = "no-referrer"
permissionsPolicyValue = "accelerometer=(), " +
"autoplay=(), " +
"camera=(), " +
"display-capture=(), " +
"encrypted-media=(), " +
"fullscreen=(), " +
"geolocation=(), " +
"gyroscope=(), " +
"magnetometer=(), " +
"microphone=(), " +
"midi=(), " +
"payment=(), " +
"picture-in-picture=(), " +
"publickey-credentials-get=(), " +
"screen-wake-lock=(), " +
"usb=(), " +
"xr-spatial-tracking=()"
)
// Params contains dependencies for Middleware.
type Params struct {
fx.In
@@ -240,37 +186,6 @@ func (m *Middleware) CORS() func(http.Handler) http.Handler {
})
}
// SecurityHeaders returns middleware that sets the security response
// headers required for production internet exposure on every response.
//
// The headers are set before the request reaches the next handler so
// that they are present on every response, including panics recovered
// by chi's Recoverer and timeouts produced by chi's Timeout.
func (m *Middleware) SecurityHeaders() func(http.Handler) http.Handler {
return func(next http.Handler) http.Handler {
return http.HandlerFunc(func(
writer http.ResponseWriter,
request *http.Request,
) {
header := writer.Header()
header.Set("Strict-Transport-Security", hstsValue)
header.Set("Content-Security-Policy", cspValue)
header.Set("X-Frame-Options", frameOptionsValue)
header.Set(
"X-Content-Type-Options",
contentTypeOptionsValue,
)
header.Set("Referrer-Policy", referrerPolicyValue)
header.Set(
"Permissions-Policy",
permissionsPolicyValue,
)
next.ServeHTTP(writer, request)
})
}
}
// MetricsAuth returns basic auth middleware for /metrics.
func (m *Middleware) MetricsAuth() func(http.Handler) http.Handler {
if m.params.Config.MetricsUsername == "" {
internal/middleware/middleware_test.go
-334
View File
@@ -1,334 +0,0 @@
package middleware_test
import (
"net/http"
"net/http/httptest"
"strings"
"testing"
"github.com/go-chi/chi/v5"
"go.uber.org/fx/fxtest"
"sneak.berlin/go/dnswatcher/internal/config"
"sneak.berlin/go/dnswatcher/internal/globals"
"sneak.berlin/go/dnswatcher/internal/handlers"
"sneak.berlin/go/dnswatcher/internal/logger"
"sneak.berlin/go/dnswatcher/internal/middleware"
"sneak.berlin/go/dnswatcher/internal/notify"
"sneak.berlin/go/dnswatcher/internal/state"
)
// Expected security header values, spelled out literally so that any
// change to the middleware has to be made deliberately here as well.
const (
wantHSTS = "max-age=31536000; includeSubDomains"
wantCSP = "default-src 'self'; " +
"script-src 'none'; " +
"style-src 'self'; " +
"img-src 'self'; " +
"font-src 'none'; " +
"connect-src 'none'; " +
"object-src 'none'; " +
"base-uri 'none'; " +
"form-action 'none'; " +
"frame-ancestors 'none'"
wantFrameOptions = "DENY"
wantContentTypeOptions = "nosniff"
wantReferrerPolicy = "no-referrer"
wantPermissionsPolicy = "accelerometer=(), " +
"autoplay=(), " +
"camera=(), " +
"display-capture=(), " +
"encrypted-media=(), " +
"fullscreen=(), " +
"geolocation=(), " +
"gyroscope=(), " +
"magnetometer=(), " +
"microphone=(), " +
"midi=(), " +
"payment=(), " +
"picture-in-picture=(), " +
"publickey-credentials-get=(), " +
"screen-wake-lock=(), " +
"usb=(), " +
"xr-spatial-tracking=()"
)
// stylesheetPath is the only subresource the dashboard loads.
const stylesheetPath = "/s/css/tailwind.min.css"
// newTestLogger builds a logger for direct component construction.
func newTestLogger(t *testing.T) *logger.Logger {
t.Helper()
glob, err := globals.New(nil)
if err != nil {
t.Fatalf("globals.New: %v", err)
}
log, err := logger.New(nil, logger.Params{Globals: glob})
if err != nil {
t.Fatalf("logger.New: %v", err)
}
return log
}
// newTestMiddleware builds a Middleware without an fx application.
func newTestMiddleware(t *testing.T) *middleware.Middleware {
t.Helper()
glob, err := globals.New(nil)
if err != nil {
t.Fatalf("globals.New: %v", err)
}
mw, err := middleware.New(nil, middleware.Params{
Logger: newTestLogger(t),
Globals: glob,
Config: &config.Config{},
})
if err != nil {
t.Fatalf("middleware.New: %v", err)
}
return mw
}
// serveWithSecurityHeaders runs a GET through SecurityHeaders and
// returns the recorded response.
func serveWithSecurityHeaders(
t *testing.T,
target string,
handler http.Handler,
) *httptest.ResponseRecorder {
t.Helper()
mw := newTestMiddleware(t)
rec := httptest.NewRecorder()
req := httptest.NewRequestWithContext(
t.Context(), http.MethodGet, target, nil,
)
mw.SecurityHeaders()(handler).ServeHTTP(rec, req)
return rec
}
// okHandler writes a trivial 200 response.
func okHandler() http.Handler {
return http.HandlerFunc(func(
writer http.ResponseWriter,
_ *http.Request,
) {
writer.WriteHeader(http.StatusOK)
})
}
func TestSecurityHeaders(t *testing.T) {
t.Parallel()
tests := []struct {
name string
header string
want string
}{
{
"hsts",
"Strict-Transport-Security",
wantHSTS,
},
{
"csp",
"Content-Security-Policy",
wantCSP,
},
{
"frame options",
"X-Frame-Options",
wantFrameOptions,
},
{
"content type options",
"X-Content-Type-Options",
wantContentTypeOptions,
},
{
"referrer policy",
"Referrer-Policy",
wantReferrerPolicy,
},
{
"permissions policy",
"Permissions-Policy",
wantPermissionsPolicy,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
rec := serveWithSecurityHeaders(t, "/", okHandler())
got := rec.Header().Get(tt.header)
if got != tt.want {
t.Errorf(
"%s = %q, want %q",
tt.header, got, tt.want,
)
}
})
}
}
// TestSecurityHeadersCSPDirectives guards the properties the repo
// policy requires of the content security policy itself.
func TestSecurityHeadersCSPDirectives(t *testing.T) {
t.Parallel()
rec := serveWithSecurityHeaders(t, "/", okHandler())
csp := rec.Header().Get("Content-Security-Policy")
forbidden := []string{"unsafe-inline", "unsafe-eval"}
for _, directive := range forbidden {
if strings.Contains(csp, directive) {
t.Errorf("CSP must not contain %q: %q", directive, csp)
}
}
required := []string{
"default-src 'self'",
"script-src 'none'",
"style-src 'self'",
"frame-ancestors 'none'",
}
for _, directive := range required {
if !strings.Contains(csp, directive) {
t.Errorf("CSP must contain %q: %q", directive, csp)
}
}
}
// TestSecurityHeadersOnErrorResponse verifies the headers are emitted
// even when the wrapped handler fails, since they are set before the
// handler runs.
func TestSecurityHeadersOnErrorResponse(t *testing.T) {
t.Parallel()
failing := http.HandlerFunc(func(
writer http.ResponseWriter,
_ *http.Request,
) {
http.Error(
writer,
"boom",
http.StatusInternalServerError,
)
})
rec := serveWithSecurityHeaders(t, "/api/v1/status", failing)
if rec.Code != http.StatusInternalServerError {
t.Fatalf("status = %d, want 500", rec.Code)
}
if got := rec.Header().Get(
"X-Content-Type-Options",
); got != wantContentTypeOptions {
t.Errorf(
"X-Content-Type-Options = %q, want %q",
got, wantContentTypeOptions,
)
}
if got := rec.Header().Get(
"Strict-Transport-Security",
); got != wantHSTS {
t.Errorf(
"Strict-Transport-Security = %q, want %q",
got, wantHSTS,
)
}
}
// newTestHandlers builds real Handlers with empty monitoring state.
func newTestHandlers(t *testing.T) *handlers.Handlers {
t.Helper()
glob, err := globals.New(nil)
if err != nil {
t.Fatalf("globals.New: %v", err)
}
log := newTestLogger(t)
notifier, err := notify.New(fxtest.NewLifecycle(t), notify.Params{
Logger: log,
Config: &config.Config{},
})
if err != nil {
t.Fatalf("notify.New: %v", err)
}
hnd, err := handlers.New(nil, handlers.Params{
Logger: log,
Globals: glob,
State: state.NewForTest(),
Notify: notifier,
})
if err != nil {
t.Fatalf("handlers.New: %v", err)
}
return hnd
}
// TestDashboardRendersWithSecurityHeaders renders the real dashboard
// through the middleware and checks that the policy still permits the
// one stylesheet the page loads.
func TestDashboardRendersWithSecurityHeaders(t *testing.T) {
t.Parallel()
mw := newTestMiddleware(t)
hnd := newTestHandlers(t)
router := chi.NewRouter()
router.Use(mw.SecurityHeaders())
router.Get("/", hnd.HandleDashboard())
rec := httptest.NewRecorder()
req := httptest.NewRequestWithContext(
t.Context(), http.MethodGet, "/", nil,
)
router.ServeHTTP(rec, req)
if rec.Code != http.StatusOK {
t.Fatalf("status = %d, want 200", rec.Code)
}
body := rec.Body.String()
if !strings.Contains(body, stylesheetPath) {
t.Errorf("dashboard does not reference %q", stylesheetPath)
}
if !strings.Contains(body, "dnswatcher") {
t.Errorf("dashboard body looks empty: %d bytes", len(body))
}
csp := rec.Header().Get("Content-Security-Policy")
if csp != wantCSP {
t.Errorf("CSP = %q, want %q", csp, wantCSP)
}
// The stylesheet is same-origin, so style-src 'self' allows it.
if !strings.Contains(csp, "style-src 'self'") {
t.Errorf("CSP would block %q: %q", stylesheetPath, csp)
}
}
internal/notify/delivery_test.go
-1111
View File
File diff suppressed because it is too large Load Diff
internal/notify/export_test.go
-121
View File
@@ -1,121 +0,0 @@
package notify
import (
"context"
"io"
"log/slog"
"net/http"
"net/url"
"time"
)
// NtfyPriority exports ntfyPriority for testing.
func NtfyPriority(priority string) string {
return ntfyPriority(priority)
}
// SlackColor exports slackColor for testing.
func SlackColor(priority string) string {
return slackColor(priority)
}
// NewRequestForTest exports newRequest for testing.
func NewRequestForTest(
ctx context.Context,
method string,
target *url.URL,
body io.Reader,
) *http.Request {
return newRequest(ctx, method, target, body)
}
// NewTestService creates a Service suitable for unit testing.
// It discards log output and uses the given transport.
func NewTestService(transport http.RoundTripper) *Service {
return newService(slog.New(slog.DiscardHandler), transport)
}
// NewTestServiceWithLogger creates a Service that writes to the
// given handler, so tests can assert on emitted log records.
func NewTestServiceWithLogger(
transport http.RoundTripper,
handler slog.Handler,
) *Service {
return newService(slog.New(handler), transport)
}
// Drain exports drain for testing.
func (svc *Service) Drain(ctx context.Context) {
svc.drain(ctx)
}
// OutstandingDeliveries reports how many delivery goroutines
// are currently tracked as in flight.
func (svc *Service) OutstandingDeliveries() int64 {
return svc.outstanding.Load()
}
// SetNtfyURL sets the ntfy URL on a Service for testing.
func (svc *Service) SetNtfyURL(u *url.URL) {
svc.ntfyURL = u
}
// SetSlackWebhookURL sets the Slack webhook URL on a
// Service for testing.
func (svc *Service) SetSlackWebhookURL(u *url.URL) {
svc.slackWebhookURL = u
}
// SetMattermostWebhookURL sets the Mattermost webhook URL on
// a Service for testing.
func (svc *Service) SetMattermostWebhookURL(u *url.URL) {
svc.mattermostWebhookURL = u
}
// SendNtfy exports sendNtfy for testing.
func (svc *Service) SendNtfy(
ctx context.Context,
topicURL *url.URL,
title, message, priority string,
) error {
return svc.sendNtfy(ctx, topicURL, title, message, priority)
}
// SendSlack exports sendSlack for testing.
func (svc *Service) SendSlack(
ctx context.Context,
webhookURL *url.URL,
title, message, priority string,
) error {
return svc.sendSlack(
ctx, webhookURL, title, message, priority,
)
}
// SetRetryConfig overrides the retry configuration for
// testing.
func (svc *Service) SetRetryConfig(cfg RetryConfig) {
svc.retryConfig = cfg
}
// SetSleepFunc overrides the sleep function so tests can
// eliminate real delays.
func (svc *Service) SetSleepFunc(
fn func(time.Duration) <-chan time.Time,
) {
svc.sleepFn = fn
}
// DeliverWithRetry exports deliverWithRetry for testing.
func (svc *Service) DeliverWithRetry(
ctx context.Context,
endpoint string,
fn func(context.Context) error,
) error {
return svc.deliverWithRetry(ctx, endpoint, fn)
}
// BackoffDuration exports RetryConfig.backoff for testing.
func (rc RetryConfig) BackoffDuration(attempt int) time.Duration {
return rc.defaults().backoff(attempt)
}
internal/notify/history.go
-62
View File
@@ -1,62 +0,0 @@
package notify
import (
"sync"
"time"
)
// maxAlertHistory is the maximum number of alerts to retain.
const maxAlertHistory = 100
// AlertEntry represents a single notification that was sent.
type AlertEntry struct {
Timestamp time.Time
Title string
Message string
Priority string
}
// AlertHistory is a thread-safe ring buffer that stores
// the most recent alerts.
type AlertHistory struct {
mu sync.RWMutex
entries [maxAlertHistory]AlertEntry
count int
index int
}
// NewAlertHistory creates a new empty AlertHistory.
func NewAlertHistory() *AlertHistory {
return &AlertHistory{}
}
// Add records a new alert entry in the ring buffer.
func (h *AlertHistory) Add(entry AlertEntry) {
h.mu.Lock()
defer h.mu.Unlock()
h.entries[h.index] = entry
h.index = (h.index + 1) % maxAlertHistory
if h.count < maxAlertHistory {
h.count++
}
}
// Recent returns the stored alerts in reverse chronological
// order (newest first). Returns at most maxAlertHistory entries.
func (h *AlertHistory) Recent() []AlertEntry {
h.mu.RLock()
defer h.mu.RUnlock()
result := make([]AlertEntry, h.count)
for i := range h.count {
// Walk backwards from the most recent entry.
idx := (h.index - 1 - i + maxAlertHistory) %
maxAlertHistory
result[i] = h.entries[idx]
}
return result
}
internal/notify/history_test.go
-88
View File
@@ -1,88 +0,0 @@
package notify_test
import (
"testing"
"time"
"sneak.berlin/go/dnswatcher/internal/notify"
)
func TestAlertHistoryEmpty(t *testing.T) {
t.Parallel()
h := notify.NewAlertHistory()
entries := h.Recent()
if len(entries) != 0 {
t.Fatalf("expected 0 entries, got %d", len(entries))
}
}
func TestAlertHistoryAddAndRecent(t *testing.T) {
t.Parallel()
h := notify.NewAlertHistory()
now := time.Now().UTC()
h.Add(notify.AlertEntry{
Timestamp: now.Add(-2 * time.Minute),
Title: "first",
Message: "msg1",
Priority: prioInfo,
})
h.Add(notify.AlertEntry{
Timestamp: now.Add(-1 * time.Minute),
Title: "second",
Message: "msg2",
Priority: prioWarning,
})
entries := h.Recent()
if len(entries) != 2 {
t.Fatalf("expected 2 entries, got %d", len(entries))
}
// Newest first.
if entries[0].Title != "second" {
t.Errorf(
"expected newest first, got %q", entries[0].Title,
)
}
if entries[1].Title != "first" {
t.Errorf(
"expected oldest second, got %q", entries[1].Title,
)
}
}
func TestAlertHistoryOverflow(t *testing.T) {
t.Parallel()
h := notify.NewAlertHistory()
const totalEntries = 110
// Fill beyond capacity.
for i := range totalEntries {
h.Add(notify.AlertEntry{
Timestamp: time.Now().UTC(),
Title: "alert",
Message: "msg",
Priority: string(rune('0' + i%10)),
})
}
entries := h.Recent()
const maxHistory = 100
if len(entries) != maxHistory {
t.Fatalf(
"expected %d entries, got %d",
maxHistory, len(entries),
)
}
}
internal/notify/notify.go
+57 -130
View File
@@ -12,8 +12,6 @@ import (
"log/slog"
"net/http"
"net/url"
"sync"
"sync/atomic"
"time"
"go.uber.org/fx"
@@ -114,44 +112,18 @@ type Service struct {
ntfyURL *url.URL
slackWebhookURL *url.URL
mattermostWebhookURL *url.URL
history *AlertHistory
retryConfig RetryConfig
sleepFn func(time.Duration) <-chan time.Time
// Shutdown draining state. drainMu guards draining and
// serialises it against the counter increment in
// startDelivery; inFlight tracks the delivery goroutines
// themselves and outstanding mirrors its count so a timed
// out drain can report how many were abandoned.
drainMu sync.Mutex
draining bool
inFlight sync.WaitGroup
outstanding atomic.Int64
abandon chan struct{}
abandonOnce sync.Once
}
// newService builds a Service with the fields every Service
// needs regardless of how it was constructed.
func newService(
log *slog.Logger,
transport http.RoundTripper,
) *Service {
return &Service{
log: log,
transport: transport,
history: NewAlertHistory(),
abandon: make(chan struct{}),
}
}
// New creates a new notify Service.
func New(
lifecycle fx.Lifecycle,
_ fx.Lifecycle,
params Params,
) (*Service, error) {
svc := newService(params.Logger.Get(), http.DefaultTransport)
svc.config = params.Config
svc := &Service{
log: params.Logger.Get(),
transport: http.DefaultTransport,
config: params.Config,
}
if params.Config.NtfyTopic != "" {
u, err := ValidateWebhookURL(
@@ -192,113 +164,68 @@ func New(
svc.mattermostWebhookURL = u
}
lifecycle.Append(fx.Hook{
OnStop: func(ctx context.Context) error {
svc.drain(ctx)
return nil
},
})
return svc, nil
}
// History returns the alert history for reading recent alerts.
func (svc *Service) History() *AlertHistory {
return svc.history
}
// SendNotification sends a notification to all configured
// endpoints and records it in the alert history.
// endpoints.
func (svc *Service) SendNotification(
ctx context.Context,
title, message, priority string,
) {
svc.history.Add(AlertEntry{
Timestamp: time.Now().UTC(),
Title: title,
Message: message,
Priority: priority,
})
if svc.ntfyURL != nil {
go func() {
notifyCtx := context.WithoutCancel(ctx)
svc.dispatchNtfy(ctx, title, message, priority)
svc.dispatchSlack(ctx, title, message, priority)
svc.dispatchMattermost(ctx, title, message, priority)
}
// dispatch delivers a notification to one endpoint on a
// tracked background goroutine.
//
// The delivery context is detached from ctx with
// context.WithoutCancel so that a cancelled caller does not
// kill a delivery already under way; the shutdown drain, not
// the caller, decides how long deliveries may keep running.
func (svc *Service) dispatch(
ctx context.Context,
endpoint string,
send func(context.Context) error,
) {
notifyCtx := context.WithoutCancel(ctx)
svc.startDelivery(endpoint, func() {
err := svc.deliverWithRetry(notifyCtx, endpoint, send)
if err != nil {
svc.log.Error(
"failed to send notification after retries",
"endpoint", endpoint,
"error", err,
)
}
})
}
func (svc *Service) dispatchNtfy(
ctx context.Context,
title, message, priority string,
) {
if svc.ntfyURL == nil {
return
}
svc.dispatch(ctx, "ntfy", func(c context.Context) error {
return svc.sendNtfy(
c, svc.ntfyURL, title, message, priority,
)
})
}
func (svc *Service) dispatchSlack(
ctx context.Context,
title, message, priority string,
) {
if svc.slackWebhookURL == nil {
return
}
svc.dispatch(ctx, "slack", func(c context.Context) error {
return svc.sendSlack(
c, svc.slackWebhookURL, title, message, priority,
)
})
}
func (svc *Service) dispatchMattermost(
ctx context.Context,
title, message, priority string,
) {
if svc.mattermostWebhookURL == nil {
return
}
svc.dispatch(
ctx, "mattermost",
func(c context.Context) error {
return svc.sendSlack(
c, svc.mattermostWebhookURL,
err := svc.sendNtfy(
notifyCtx,
svc.ntfyURL,
title, message, priority,
)
},
)
if err != nil {
svc.log.Error(
"failed to send ntfy notification",
"error", err,
)
}
}()
}
if svc.slackWebhookURL != nil {
go func() {
notifyCtx := context.WithoutCancel(ctx)
err := svc.sendSlack(
notifyCtx,
svc.slackWebhookURL,
title, message, priority,
)
if err != nil {
svc.log.Error(
"failed to send slack notification",
"error", err,
)
}
}()
}
if svc.mattermostWebhookURL != nil {
go func() {
notifyCtx := context.WithoutCancel(ctx)
err := svc.sendSlack(
notifyCtx,
svc.mattermostWebhookURL,
title, message, priority,
)
if err != nil {
svc.log.Error(
"failed to send mattermost notification",
"error", err,
)
}
}()
}
}
func (svc *Service) sendNtfy(
internal/notify/retry.go
-148
View File
@@ -1,148 +0,0 @@
package notify
import (
"context"
"fmt"
"math"
"math/rand/v2"
"time"
)
// Retry defaults.
const (
// DefaultMaxRetries is the number of additional attempts
// after the first failure.
DefaultMaxRetries = 5
// DefaultBaseDelay is the initial delay before the first
// retry attempt.
DefaultBaseDelay = 1 * time.Second
// DefaultMaxDelay caps the computed backoff delay.
DefaultMaxDelay = 60 * time.Second
// backoffMultiplier is the exponential growth factor.
backoffMultiplier = 2
// jitterFraction controls the ±random spread applied
// to each delay (0.25 = ±25%).
jitterFraction = 0.25
)
// RetryConfig holds tuning knobs for the retry loop.
// Zero values fall back to the package defaults above.
type RetryConfig struct {
MaxRetries int
BaseDelay time.Duration
MaxDelay time.Duration
}
// defaults returns a copy with zero fields replaced by
// package defaults.
func (rc RetryConfig) defaults() RetryConfig {
if rc.MaxRetries <= 0 {
rc.MaxRetries = DefaultMaxRetries
}
if rc.BaseDelay <= 0 {
rc.BaseDelay = DefaultBaseDelay
}
if rc.MaxDelay <= 0 {
rc.MaxDelay = DefaultMaxDelay
}
return rc
}
// backoff computes the delay for attempt n (0-indexed) with
// jitter. The raw delay is BaseDelay * 2^n, capped at
// MaxDelay, then randomised by ±jitterFraction.
func (rc RetryConfig) backoff(attempt int) time.Duration {
raw := float64(rc.BaseDelay) *
math.Pow(backoffMultiplier, float64(attempt))
if raw > float64(rc.MaxDelay) {
raw = float64(rc.MaxDelay)
}
// Apply jitter: uniform in [raw*(1-j), raw*(1+j)].
lo := raw * (1 - jitterFraction)
hi := raw * (1 + jitterFraction)
jittered := lo + rand.Float64()*(hi-lo) //nolint:gosec // jitter needs no crypto/rand
return time.Duration(jittered)
}
// deliverWithRetry calls fn, retrying on error with
// exponential backoff. It logs every failed attempt and
// returns the last error if all attempts are exhausted.
func (svc *Service) deliverWithRetry(
ctx context.Context,
endpoint string,
fn func(context.Context) error,
) error {
cfg := svc.retryConfig.defaults()
var lastErr error
// attempt 0 is the initial call; attempts 1..MaxRetries
// are retries.
for attempt := range cfg.MaxRetries + 1 {
lastErr = fn(ctx)
if lastErr == nil {
if attempt > 0 {
svc.log.Info(
"notification delivered after retry",
"endpoint", endpoint,
"attempt", attempt+1,
)
}
return nil
}
// Last attempt — don't sleep, just return.
if attempt == cfg.MaxRetries {
break
}
delay := cfg.backoff(attempt)
svc.log.Warn(
"notification delivery failed, retrying",
"endpoint", endpoint,
"attempt", attempt+1,
"maxAttempts", cfg.MaxRetries+1,
"retryIn", delay,
"error", lastErr,
)
select {
case <-ctx.Done():
return ctx.Err()
case <-svc.abandon:
// Shutdown drained past its deadline; stop
// sleeping rather than outlive the process.
// A nil channel (Service built without a
// constructor) simply never fires.
return fmt.Errorf(
"%w: %s", ErrDeliveryAbandoned, endpoint,
)
case <-svc.sleepFunc(delay):
}
}
return lastErr
}
// sleepFunc returns a channel that closes after d.
// It is a field-level indirection so tests can override it.
func (svc *Service) sleepFunc(d time.Duration) <-chan time.Time {
if svc.sleepFn != nil {
return svc.sleepFn(d)
}
return time.After(d)
}
internal/notify/retry_test.go
-493
View File
@@ -1,493 +0,0 @@
package notify_test
import (
"context"
"errors"
"net/http"
"net/http/httptest"
"net/url"
"sync"
"sync/atomic"
"testing"
"time"
"sneak.berlin/go/dnswatcher/internal/notify"
)
// Static test errors (err113).
var (
errTransient = errors.New("transient failure")
errPermanent = errors.New("permanent failure")
errFail = errors.New("fail")
)
// instantSleep returns a closed channel immediately, removing
// real delays from tests.
func instantSleep(_ time.Duration) <-chan time.Time {
ch := make(chan time.Time, 1)
ch <- time.Now()
return ch
}
// ── backoff calculation ───────────────────────────────────
func TestBackoffDurationIncreases(t *testing.T) {
t.Parallel()
cfg := notify.RetryConfig{
MaxRetries: 5,
BaseDelay: 1 * time.Second,
MaxDelay: 30 * time.Second,
}
prev := time.Duration(0)
// With jitter the exact value varies, but the trend
// should be increasing for the first few attempts.
for attempt := range 4 {
d := cfg.BackoffDuration(attempt)
if d <= 0 {
t.Fatalf(
"attempt %d: backoff must be positive, got %v",
attempt, d,
)
}
// Allow jitter to occasionally flatten a step, but
// the midpoint (no-jitter) should be strictly higher.
midpoint := cfg.BaseDelay * (1 << attempt)
if attempt > 0 && midpoint <= prev {
t.Fatalf(
"midpoint should grow: attempt %d midpoint=%v prev=%v",
attempt, midpoint, prev,
)
}
prev = midpoint
}
}
func TestBackoffDurationCappedAtMax(t *testing.T) {
t.Parallel()
cfg := notify.RetryConfig{
MaxRetries: 5,
BaseDelay: 1 * time.Second,
MaxDelay: 5 * time.Second,
}
// Attempt 10 would be 1024s without capping.
d := cfg.BackoffDuration(10)
// With ±25% jitter on a 5s cap: max is 6.25s.
const maxWithJitter = 5*time.Second +
5*time.Second/4 +
time.Millisecond // rounding margin
if d > maxWithJitter {
t.Errorf(
"backoff %v exceeds max+jitter %v",
d, maxWithJitter,
)
}
}
// ── deliverWithRetry ──────────────────────────────────────
func TestDeliverWithRetrySucceedsFirstAttempt(t *testing.T) {
t.Parallel()
svc := notify.NewTestService(http.DefaultTransport)
svc.SetSleepFunc(instantSleep)
var calls atomic.Int32
err := svc.DeliverWithRetry(
context.Background(), "test",
func(_ context.Context) error {
calls.Add(1)
return nil
},
)
if err != nil {
t.Fatalf("unexpected error: %v", err)
}
if calls.Load() != 1 {
t.Errorf("expected 1 call, got %d", calls.Load())
}
}
func TestDeliverWithRetryRetriesOnFailure(t *testing.T) {
t.Parallel()
svc := notify.NewTestService(http.DefaultTransport)
svc.SetSleepFunc(instantSleep)
svc.SetRetryConfig(notify.RetryConfig{
MaxRetries: 3,
BaseDelay: time.Millisecond,
MaxDelay: 10 * time.Millisecond,
})
var calls atomic.Int32
// Fail twice, then succeed on the third attempt.
err := svc.DeliverWithRetry(
context.Background(), "test",
func(_ context.Context) error {
n := calls.Add(1)
if n <= 2 {
return errTransient
}
return nil
},
)
if err != nil {
t.Fatalf("expected success after retries: %v", err)
}
if calls.Load() != 3 {
t.Errorf("expected 3 calls, got %d", calls.Load())
}
}
func TestDeliverWithRetryExhaustsAttempts(t *testing.T) {
t.Parallel()
svc := notify.NewTestService(http.DefaultTransport)
svc.SetSleepFunc(instantSleep)
svc.SetRetryConfig(notify.RetryConfig{
MaxRetries: 2,
BaseDelay: time.Millisecond,
MaxDelay: 10 * time.Millisecond,
})
var calls atomic.Int32
err := svc.DeliverWithRetry(
context.Background(), "test",
func(_ context.Context) error {
calls.Add(1)
return errPermanent
},
)
if err == nil {
t.Fatal("expected error when all retries exhausted")
}
if !errors.Is(err, errPermanent) {
t.Errorf("expected permanent failure, got: %v", err)
}
// 1 initial + 2 retries = 3 total.
if calls.Load() != 3 {
t.Errorf("expected 3 calls, got %d", calls.Load())
}
}
func TestDeliverWithRetryRespectsContextCancellation(
t *testing.T,
) {
t.Parallel()
svc := notify.NewTestService(http.DefaultTransport)
svc.SetRetryConfig(notify.RetryConfig{
MaxRetries: 5,
BaseDelay: time.Millisecond,
MaxDelay: 10 * time.Millisecond,
})
// Use a blocking sleep so the context cancellation is
// the only way out.
svc.SetSleepFunc(func(_ time.Duration) <-chan time.Time {
return make(chan time.Time) // never fires
})
ctx, cancel := context.WithCancel(context.Background())
done := make(chan error, 1)
go func() {
done <- svc.DeliverWithRetry(
ctx, "test",
func(_ context.Context) error {
return errFail
},
)
}()
// Wait for the first failure + retry sleep to be
// entered, then cancel.
time.Sleep(50 * time.Millisecond)
cancel()
select {
case err := <-done:
if !errors.Is(err, context.Canceled) {
t.Errorf(
"expected context.Canceled, got: %v", err,
)
}
case <-time.After(2 * time.Second):
t.Fatal("deliverWithRetry did not return after cancel")
}
}
// ── integration: SendNotification with retry ──────────────
func TestSendNotificationRetriesTransientFailure(
t *testing.T,
) {
t.Parallel()
var (
mu sync.Mutex
attempts int
)
srv := httptest.NewServer(
http.HandlerFunc(
func(w http.ResponseWriter, _ *http.Request) {
mu.Lock()
attempts++
n := attempts
mu.Unlock()
if n <= 2 {
w.WriteHeader(
http.StatusInternalServerError,
)
return
}
w.WriteHeader(http.StatusOK)
}),
)
defer srv.Close()
svc := newRetryTestService(srv.URL, "ntfy")
svc.SendNotification(
context.Background(),
"Retry Test", "body", "warning",
)
waitForCondition(t, func() bool {
mu.Lock()
defer mu.Unlock()
return attempts >= 3
})
}
// newRetryTestService creates a test service with instant
// sleep and low retry delays for the named endpoint.
func newRetryTestService(
rawURL, endpoint string,
) *notify.Service {
svc := notify.NewTestService(http.DefaultTransport)
svc.SetSleepFunc(instantSleep)
svc.SetRetryConfig(notify.RetryConfig{
MaxRetries: 3,
BaseDelay: time.Millisecond,
MaxDelay: 10 * time.Millisecond,
})
u, _ := url.Parse(rawURL)
switch endpoint {
case "ntfy":
svc.SetNtfyURL(u)
case "slack":
svc.SetSlackWebhookURL(u)
case "mattermost":
svc.SetMattermostWebhookURL(u)
}
return svc
}
func TestSendNotificationAllEndpointsRetrySetup(
t *testing.T,
) {
t.Parallel()
result := newEndpointRetryResult()
ntfySrv, slackSrv, mmSrv := newRetryServers(result)
defer ntfySrv.Close()
defer slackSrv.Close()
defer mmSrv.Close()
svc := buildAllEndpointRetryService(
ntfySrv.URL, slackSrv.URL, mmSrv.URL,
)
svc.SendNotification(
context.Background(),
"Multi-Retry", "testing", "error",
)
assertAllEndpointsRetried(t, result)
}
// endpointRetryResult tracks per-endpoint retry state.
type endpointRetryResult struct {
mu sync.Mutex
ntfyAttempts int
slackAttempts int
mmAttempts int
ntfyOK bool
slackOK bool
mmOK bool
}
func newEndpointRetryResult() *endpointRetryResult {
return &endpointRetryResult{}
}
func newRetryServers(
r *endpointRetryResult,
) (*httptest.Server, *httptest.Server, *httptest.Server) {
mk := func(
attempts *int, ok *bool,
) *httptest.Server {
return httptest.NewServer(
http.HandlerFunc(
func(w http.ResponseWriter, _ *http.Request) {
r.mu.Lock()
*attempts++
n := *attempts
r.mu.Unlock()
if n == 1 {
w.WriteHeader(
http.StatusServiceUnavailable,
)
return
}
r.mu.Lock()
*ok = true
r.mu.Unlock()
w.WriteHeader(http.StatusOK)
}),
)
}
return mk(&r.ntfyAttempts, &r.ntfyOK),
mk(&r.slackAttempts, &r.slackOK),
mk(&r.mmAttempts, &r.mmOK)
}
func buildAllEndpointRetryService(
ntfyURL, slackURL, mmURL string,
) *notify.Service {
svc := notify.NewTestService(http.DefaultTransport)
svc.SetSleepFunc(instantSleep)
svc.SetRetryConfig(notify.RetryConfig{
MaxRetries: 3,
BaseDelay: time.Millisecond,
MaxDelay: 10 * time.Millisecond,
})
nu, _ := url.Parse(ntfyURL)
su, _ := url.Parse(slackURL)
mu, _ := url.Parse(mmURL)
svc.SetNtfyURL(nu)
svc.SetSlackWebhookURL(su)
svc.SetMattermostWebhookURL(mu)
return svc
}
func assertAllEndpointsRetried(
t *testing.T,
r *endpointRetryResult,
) {
t.Helper()
waitForCondition(t, func() bool {
r.mu.Lock()
defer r.mu.Unlock()
return r.ntfyOK && r.slackOK && r.mmOK
})
r.mu.Lock()
defer r.mu.Unlock()
if r.ntfyAttempts < 2 {
t.Errorf(
"ntfy: expected >= 2 attempts, got %d",
r.ntfyAttempts,
)
}
if r.slackAttempts < 2 {
t.Errorf(
"slack: expected >= 2 attempts, got %d",
r.slackAttempts,
)
}
if r.mmAttempts < 2 {
t.Errorf(
"mattermost: expected >= 2 attempts, got %d",
r.mmAttempts,
)
}
}
func TestSendNotificationPermanentFailureLogsError(
t *testing.T,
) {
t.Parallel()
var (
mu sync.Mutex
attempts int
)
srv := httptest.NewServer(
http.HandlerFunc(
func(w http.ResponseWriter, _ *http.Request) {
mu.Lock()
attempts++
mu.Unlock()
w.WriteHeader(
http.StatusInternalServerError,
)
}),
)
defer srv.Close()
svc := newRetryTestService(srv.URL, "slack")
svc.SetRetryConfig(notify.RetryConfig{
MaxRetries: 2,
BaseDelay: time.Millisecond,
MaxDelay: 10 * time.Millisecond,
})
svc.SendNotification(
context.Background(),
"Permanent Fail", "body", "error",
)
// 1 initial + 2 retries = 3 total.
waitForCondition(t, func() bool {
mu.Lock()
defer mu.Unlock()
return attempts >= 3
})
}
internal/notify/shutdown.go
-119
View File
@@ -1,119 +0,0 @@
package notify
import (
"context"
"errors"
)
// ErrDeliveryAbandoned is returned by a retry loop that was
// cut short because shutdown drained past its deadline.
var ErrDeliveryAbandoned = errors.New(
"notification delivery abandoned at shutdown",
)
// startDelivery runs fn on its own goroutine while tracking it,
// so that drain can wait for it during shutdown.
//
// The WaitGroup counter is incremented here, on the caller's
// goroutine, before the worker exists: incrementing it inside
// the worker would race with drain's Wait and could let
// shutdown sail past a delivery that had not started yet.
//
// Once draining has begun the delivery is refused outright
// rather than queued, so a steady stream of newly submitted
// notifications cannot keep extending the drain.
func (svc *Service) startDelivery(endpoint string, fn func()) {
svc.drainMu.Lock()
if svc.draining {
svc.drainMu.Unlock()
svc.log.Warn(
"notification not dispatched: shutdown in progress",
"endpoint", endpoint,
)
return
}
svc.outstanding.Add(1)
// WaitGroup.Go increments the counter synchronously, here,
// and only then starts the goroutine.
svc.inFlight.Go(func() {
// Runs before the WaitGroup counter is decremented, so
// a drain that times out reports an accurate count.
defer svc.outstanding.Add(-1)
fn()
})
svc.drainMu.Unlock()
}
// drain waits for in-flight notification deliveries to finish.
//
// It first stops accepting new deliveries, then waits until
// either every outstanding delivery has completed or ctx
// expires — whichever comes first. ctx is the context fx
// passes to the OnStop hook, so a permanently dead webhook
// cannot hang shutdown indefinitely.
//
// When the deadline arrives with deliveries still outstanding,
// the count is logged at warn level and the abandon channel is
// closed, which releases any retry loop sleeping in backoff.
// Deliveries already inside an HTTP round trip are bounded by
// the existing httpClientTimeout instead.
//
// A ctx that is already expired on entry is not by itself cause
// for alarm: if nothing is outstanding there is nothing to
// abandon, and the drain says so at debug level rather than
// warning about deliveries that do not exist.
func (svc *Service) drain(ctx context.Context) {
svc.drainMu.Lock()
svc.draining = true
svc.drainMu.Unlock()
done := make(chan struct{})
go func() {
svc.inFlight.Wait()
close(done)
}()
select {
case <-done:
svc.log.Debug(
"all in-flight notifications completed",
)
case <-ctx.Done():
// outstanding is decremented before the WaitGroup
// counter, and startDelivery can no longer add to it
// now that draining is set, so a zero here means every
// delivery really did finish. ctx expiring in that
// state (an OnStop context that was already cancelled
// on entry is the usual way) abandons nothing, so it
// must not close abandon or warn about it.
abandoned := svc.outstanding.Load()
if abandoned == 0 {
svc.log.Debug(
"all in-flight notifications completed",
)
return
}
svc.abandonOnce.Do(func() {
if svc.abandon != nil {
close(svc.abandon)
}
})
svc.log.Warn(
"shutdown deadline reached with notifications "+
"still in flight; abandoning them",
"abandoned", abandoned,
"error", ctx.Err(),
)
}
}
internal/notify/shutdown_test.go
-531
View File
@@ -1,531 +0,0 @@
package notify_test
import (
"bytes"
"context"
"log/slog"
"net/http"
"net/http/httptest"
"net/url"
"strings"
"sync"
"sync/atomic"
"testing"
"time"
"go.uber.org/fx"
"sneak.berlin/go/dnswatcher/internal/config"
"sneak.berlin/go/dnswatcher/internal/globals"
"sneak.berlin/go/dnswatcher/internal/logger"
"sneak.berlin/go/dnswatcher/internal/notify"
)
// Timings used by the drain tests. They stay in the same
// 10-100ms band as the retry tests so the suite never waits on
// a real backoff delay.
const (
// inFlightHold is how long a delivery is kept mid-request
// before the handler is released.
inFlightHold = 30 * time.Millisecond
// drainDeadline bounds a drain that is expected to time
// out.
drainDeadline = 50 * time.Millisecond
// drainSlack is the upper bound on how long a bounded
// drain may take; generous enough for a loaded CI box,
// still far below the 20s test ceiling.
drainSlack = 2 * time.Second
// settleDelay is how long to wait before asserting that
// something did *not* happen.
settleDelay = 50 * time.Millisecond
// idleDrainBound is the upper bound on a drain that has
// nothing in flight. It is deliberately far above the cost
// of the goroutine hop through inFlight.Wait() — which
// reached 57ms on a loaded box under -race with the package's
// parallel tests — and far below drainSlack, the deadline
// such a drain is given. A drain that blocked until its
// deadline instead of returning on the WaitGroup therefore
// still fails this bound, but scheduling delay alone cannot.
idleDrainBound = 500 * time.Millisecond
)
// syncBuffer is an io.Writer safe for concurrent use, so log
// output written from delivery goroutines can be inspected.
type syncBuffer struct {
mu sync.Mutex
buf bytes.Buffer
}
func (sb *syncBuffer) Write(p []byte) (int, error) {
sb.mu.Lock()
defer sb.mu.Unlock()
return sb.buf.Write(p) //nolint:wrapcheck // test helper
}
func (sb *syncBuffer) String() string {
sb.mu.Lock()
defer sb.mu.Unlock()
return sb.buf.String()
}
// newLoggingService returns a Service writing JSON logs into
// the returned buffer.
func newLoggingService(
transport http.RoundTripper,
) (*notify.Service, *syncBuffer) {
logs := &syncBuffer{}
handler := slog.NewJSONHandler(logs, nil)
return notify.NewTestServiceWithLogger(transport, handler),
logs
}
// blockingNtfyServer returns a server whose handler signals on
// entered, waits for release, and then responds 200.
func blockingNtfyServer(
entered chan<- struct{},
release <-chan struct{},
served *atomic.Bool,
) *httptest.Server {
var once sync.Once
return httptest.NewServer(
http.HandlerFunc(
func(w http.ResponseWriter, _ *http.Request) {
once.Do(func() { close(entered) })
<-release
served.Store(true)
w.WriteHeader(http.StatusOK)
}),
)
}
// TestDrainWaitsForInFlightDelivery verifies that a delivery
// already under way when shutdown starts is allowed to finish.
func TestDrainWaitsForInFlightDelivery(t *testing.T) {
t.Parallel()
var served atomic.Bool
entered := make(chan struct{})
release := make(chan struct{})
srv := blockingNtfyServer(entered, release, &served)
defer srv.Close()
topicURL, _ := url.Parse(srv.URL)
svc := notify.NewTestService(http.DefaultTransport)
svc.SetNtfyURL(topicURL)
svc.SendNotification(
context.Background(), "t", "m", prioInfo,
)
// Make sure the delivery really is mid-request before the
// drain begins.
select {
case <-entered:
case <-time.After(drainSlack):
t.Fatal("delivery never reached the endpoint")
}
// As in TestDrainBoundedByContextDeadline: start is captured
// before the clock it is compared against, here the timer
// holding the delivery open, so elapsed covers the whole hold
// and the lower bound cannot come out short from scheduling
// delay alone.
start := time.Now()
timer := time.AfterFunc(inFlightHold, func() {
close(release)
})
defer timer.Stop()
ctx, cancel := context.WithTimeout(
context.Background(), drainSlack,
)
defer cancel()
svc.Drain(ctx)
elapsed := time.Since(start)
if !served.Load() {
t.Error(
"drain returned before the in-flight delivery " +
"completed",
)
}
if elapsed < inFlightHold {
t.Errorf(
"drain took %v, want at least %v",
elapsed, inFlightHold,
)
}
if got := svc.OutstandingDeliveries(); got != 0 {
t.Errorf("outstanding deliveries = %d, want 0", got)
}
}
// neverFires returns a channel that never delivers, standing in
// for a long backoff sleep without actually sleeping.
func neverFires(_ time.Duration) <-chan time.Time {
return make(chan time.Time)
}
// TestDrainBoundedByContextDeadline verifies that a delivery
// stuck retrying against a dead endpoint does not hold shutdown
// past the OnStop context deadline, and that the abandoned
// deliveries are logged at warn level rather than dropped
// silently.
func TestDrainBoundedByContextDeadline(t *testing.T) {
t.Parallel()
var requests atomic.Int64
srv := httptest.NewServer(
http.HandlerFunc(
func(w http.ResponseWriter, _ *http.Request) {
requests.Add(1)
w.WriteHeader(http.StatusInternalServerError)
}),
)
defer srv.Close()
topicURL, _ := url.Parse(srv.URL)
svc, logs := newLoggingService(http.DefaultTransport)
svc.SetNtfyURL(topicURL)
// Never let the backoff sleep complete: the delivery is
// parked in its retry wait until shutdown releases it.
svc.SetSleepFunc(neverFires)
svc.SetRetryConfig(notify.RetryConfig{
MaxRetries: 5,
BaseDelay: time.Hour,
MaxDelay: time.Hour,
})
svc.SendNotification(
context.Background(), "t", "m", prioError,
)
waitForCondition(t, func() bool {
return requests.Load() >= 1 &&
svc.OutstandingDeliveries() == 1
})
// start must be captured *before* the deadline clock starts,
// so that the measured interval is a superset of the deadline
// interval. Capturing it after context.WithTimeout would
// make elapsed structurally smaller than drainDeadline and
// the lower bound below unfalsifiable-by-luck: it would fail
// whenever the two statements were separated by any
// scheduling delay, and pass otherwise, regardless of what
// the drain did.
start := time.Now()
ctx, cancel := context.WithTimeout(
context.Background(), drainDeadline,
)
defer cancel()
// The upper bound is enforced by a watchdog rather than by
// measuring after the fact: a drain that is not bounded at
// all never returns here (the delivery is parked in a backoff
// that never fires), so an unbounded drain must fail this
// test promptly instead of hanging the package until the test
// binary's 30s timeout.
returned := make(chan struct{})
go func() {
defer close(returned)
svc.Drain(ctx)
}()
select {
case <-returned:
case <-time.After(drainSlack):
t.Fatalf(
"drain did not return within %v; its %v deadline "+
"did not bound it",
drainSlack, drainDeadline,
)
}
// The lower bound is the real assertion: the drain must have
// waited for its whole deadline rather than giving up on the
// outstanding delivery early. With start captured above, an
// early return is the only thing that can make it fail.
if elapsed := time.Since(start); elapsed < drainDeadline {
t.Errorf(
"drain returned after %v, before its %v deadline",
elapsed, drainDeadline,
)
}
assertAbandonLogged(t, logs.String())
// The abandoned delivery must stop retrying rather than
// outlive the drain.
waitForCondition(t, func() bool {
return svc.OutstandingDeliveries() == 0
})
}
// assertAbandonLogged checks that the drain logged the
// abandoned deliveries at warn level with a count.
func assertAbandonLogged(t *testing.T, output string) {
t.Helper()
if !strings.Contains(output, `"level":"WARN"`) {
t.Errorf(
"abandoned deliveries not logged at warn level; "+
"log output: %s",
output,
)
}
if !strings.Contains(output, `"abandoned":1`) {
t.Errorf(
"abandoned delivery count not logged; "+
"log output: %s",
output,
)
}
}
// TestDrainRefusesNewDeliveries verifies that notifications
// submitted after the drain has begun are refused and logged,
// so a stream of new work cannot extend shutdown indefinitely.
func TestDrainRefusesNewDeliveries(t *testing.T) {
t.Parallel()
var requests atomic.Int64
srv := httptest.NewServer(
http.HandlerFunc(
func(w http.ResponseWriter, _ *http.Request) {
requests.Add(1)
w.WriteHeader(http.StatusOK)
}),
)
defer srv.Close()
target, _ := url.Parse(srv.URL)
svc, logs := newLoggingService(http.DefaultTransport)
svc.SetNtfyURL(target)
svc.SetSlackWebhookURL(target)
svc.SetMattermostWebhookURL(target)
ctx, cancel := context.WithTimeout(
context.Background(), drainSlack,
)
defer cancel()
// Nothing is in flight, so this returns immediately and
// leaves the service refusing further deliveries.
svc.Drain(ctx)
for range 3 {
svc.SendNotification(
context.Background(), "t", "m", prioInfo,
)
}
time.Sleep(settleDelay)
if got := requests.Load(); got != 0 {
t.Errorf(
"%d requests reached the endpoint after drain, "+
"want 0",
got,
)
}
if got := svc.OutstandingDeliveries(); got != 0 {
t.Errorf("outstanding deliveries = %d, want 0", got)
}
output := logs.String()
if !strings.Contains(output, "shutdown in progress") {
t.Errorf(
"refused deliveries not logged; log output: %s",
output,
)
}
}
// recordingLifecycle is a minimal fx.Lifecycle that records the
// hooks appended to it, so the wiring done by notify.New can be
// inspected without standing up a whole fx application.
type recordingLifecycle struct {
hooks []fx.Hook
}
func (l *recordingLifecycle) Append(hook fx.Hook) {
l.hooks = append(l.hooks, hook)
}
// newNotifyService builds a Service through the real
// constructor, wired to the given lifecycle.
func newNotifyService(
t *testing.T,
lifecycle fx.Lifecycle,
ntfyTopic string,
) *notify.Service {
t.Helper()
g, err := globals.New(nil)
if err != nil {
t.Fatalf("globals.New: %v", err)
}
log, err := logger.New(nil, logger.Params{Globals: g})
if err != nil {
t.Fatalf("logger.New: %v", err)
}
svc, err := notify.New(lifecycle, notify.Params{
Logger: log,
Config: &config.Config{NtfyTopic: ntfyTopic},
})
if err != nil {
t.Fatalf("notify.New: %v", err)
}
return svc
}
// TestNewRegistersDrainingStopHook verifies that notify.New
// wires an OnStop hook into the fx lifecycle and that the hook
// waits for in-flight deliveries.
func TestNewRegistersDrainingStopHook(t *testing.T) {
t.Parallel()
var served atomic.Bool
entered := make(chan struct{})
release := make(chan struct{})
srv := blockingNtfyServer(entered, release, &served)
defer srv.Close()
lifecycle := &recordingLifecycle{}
svc := newNotifyService(t, lifecycle, srv.URL)
if len(lifecycle.hooks) != 1 {
t.Fatalf(
"appended %d lifecycle hooks, want 1",
len(lifecycle.hooks),
)
}
stop := lifecycle.hooks[0].OnStop
if stop == nil {
t.Fatal("lifecycle hook has no OnStop function")
}
svc.SendNotification(
context.Background(), "t", "m", prioInfo,
)
select {
case <-entered:
case <-time.After(drainSlack):
t.Fatal("delivery never reached the endpoint")
}
timer := time.AfterFunc(inFlightHold, func() {
close(release)
})
defer timer.Stop()
ctx, cancel := context.WithTimeout(
context.Background(), drainSlack,
)
defer cancel()
err := stop(ctx)
if err != nil {
t.Fatalf("OnStop returned error: %v", err)
}
if !served.Load() {
t.Error(
"OnStop returned before the in-flight delivery " +
"completed",
)
}
}
// TestDrainWithoutDeliveriesReturnsImmediately verifies the
// common case: nothing in flight, shutdown is not delayed.
func TestDrainWithoutDeliveriesReturnsImmediately(t *testing.T) {
t.Parallel()
svc := notify.NewTestService(http.DefaultTransport)
// Captured before the deadline clock, as elsewhere in this
// file; for an upper bound that is the conservative
// direction, since the measured interval can then only be
// longer than the drain itself.
start := time.Now()
ctx, cancel := context.WithTimeout(
context.Background(), drainSlack,
)
defer cancel()
svc.Drain(ctx)
if elapsed := time.Since(start); elapsed > idleDrainBound {
t.Errorf(
"drain of an idle service took %v, want well "+
"under its %v deadline",
elapsed, drainSlack,
)
}
}
// TestDrainWithCancelledContextDoesNotWarn verifies that an
// OnStop context that is already dead on entry does not produce
// an "abandoning them" warning when there was nothing in flight
// to abandon. The expired context wins the select immediately,
// so only the outstanding count can tell the difference between
// a genuine timeout and a shutdown that had simply already run
// out of time with no work left.
func TestDrainWithCancelledContextDoesNotWarn(t *testing.T) {
t.Parallel()
svc, logs := newLoggingService(http.DefaultTransport)
ctx, cancel := context.WithCancel(context.Background())
cancel()
svc.Drain(ctx)
if output := logs.String(); strings.Contains(
output, `"level":"WARN"`,
) {
t.Errorf(
"drain with nothing in flight warned about "+
"abandoned deliveries; log output: %s",
output,
)
}
}
internal/resolver/dns_client.go
+2 -2
View File
@@ -7,8 +7,8 @@ import (
"github.com/miekg/dns"
)
// DNSClient sends one DNS message to a nameserver and returns the
// reply. The resolver holds one for UDP and one for TCP.
// DNSClient abstracts DNS wire-protocol exchanges so the resolver
// can be tested without hitting real nameservers.
type DNSClient interface {
ExchangeContext(
ctx context.Context,
internal/resolver/export_test.go
-8
View File
@@ -1,8 +0,0 @@
package resolver
import "github.com/miekg/dns"
// ExtractRecordValue exports extractRecordValue for testing.
func ExtractRecordValue(rr dns.RR) string {
return extractRecordValue(rr)
}
internal/resolver/iterative.go
+5 -8
View File
@@ -608,10 +608,7 @@ func classifyResponse(resp *NameserverResponse, state queryState) {
}
}
// extractRecordValue formats a DNS RR value as a string. DNS names
// are case-insensitive and nameservers may answer in any letter case,
// so names are lower-cased to compare equal. TXT and CAA values keep
// their letter case.
// extractRecordValue formats a DNS RR value as a string.
func extractRecordValue(rr dns.RR) string {
switch r := rr.(type) {
case *dns.A:
@@ -619,22 +616,22 @@ func extractRecordValue(rr dns.RR) string {
case *dns.AAAA:
return r.AAAA.String()
case *dns.CNAME:
return strings.ToLower(r.Target)
return r.Target
case *dns.MX:
return fmt.Sprintf("%d %s", r.Preference, strings.ToLower(r.Mx))
return fmt.Sprintf("%d %s", r.Preference, r.Mx)
case *dns.TXT:
return strings.Join(r.Txt, "")
case *dns.SRV:
return fmt.Sprintf(
"%d %d %d %s",
r.Priority, r.Weight, r.Port, strings.ToLower(r.Target),
r.Priority, r.Weight, r.Port, r.Target,
)
case *dns.CAA:
return fmt.Sprintf(
"%d %s \"%s\"", r.Flag, r.Tag, r.Value,
)
case *dns.NS:
return strings.ToLower(r.Ns)
return r.Ns
default:
return ""
}
internal/resolver/iterative_test.go
-62
View File
@@ -1,62 +0,0 @@
package resolver_test
import (
"testing"
"github.com/miekg/dns"
"github.com/stretchr/testify/assert"
"sneak.berlin/go/dnswatcher/internal/resolver"
)
func TestExtractRecordValue_LetterCase(t *testing.T) {
t.Parallel()
tests := []struct {
name string
rr dns.RR
want string
}{
{
name: "MX target lower-cased",
rr: &dns.MX{Preference: 1, Mx: "ASPMX.L.GOOGLE.COM."},
want: "1 aspmx.l.google.com.",
},
{
name: "NS target lower-cased",
rr: &dns.NS{Ns: "x.ns.joker.COM."},
want: "x.ns.joker.com.",
},
{
name: "CNAME target lower-cased",
rr: &dns.CNAME{Target: "WWW.Example.Com."},
want: "www.example.com.",
},
{
name: "SRV target lower-cased",
rr: &dns.SRV{
Priority: 10, Weight: 5, Port: 443,
Target: "SIP.Example.Com.",
},
want: "10 5 443 sip.example.com.",
},
{
name: "TXT value keeps its case",
rr: &dns.TXT{Txt: []string{"Verify=AbC123"}},
want: "Verify=AbC123",
},
{
name: "CAA value keeps its case",
rr: &dns.CAA{Flag: 0, Tag: "issue", Value: "LetsEncrypt.org"},
want: `0 issue "LetsEncrypt.org"`,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
assert.Equal(t, tt.want, resolver.ExtractRecordValue(tt.rr))
})
}
}
internal/resolver/livedns_harness_test.go
-192
View File
@@ -1,192 +0,0 @@
package resolver_test
import (
"testing"
"github.com/stretchr/testify/assert"
"sneak.berlin/go/dnswatcher/internal/resolver"
)
// Tests for the live-DNS harness in livedns_test.go itself. These
// exercise pure logic; they perform no DNS resolution of any kind, so
// they neither mock DNS nor depend on it.
// Names for the synthetic status maps below. Nothing is ever queried
// at them: they are map keys handed to the package's pure counting
// helpers, not a stand-in for a nameserver.
const (
nsExample1 = "ns1.example."
nsExample2 = "ns2.example."
nsExample3 = "ns3.example."
nsExample4 = "ns4.example."
)
func TestLiveQuorumIsStrictMajority(t *testing.T) {
t.Parallel()
cases := map[int]int{
0: 1,
1: 1,
2: 2,
3: 2,
4: 3,
5: 3,
13: 7,
}
for total, want := range cases {
assert.Equal(
t, want, liveQuorum(total),
"liveQuorum(%d)", total,
)
}
}
func TestStatusCountingIgnoresSilentNameservers(t *testing.T) {
t.Parallel()
results := map[string]*resolver.NameserverResponse{
nsExample1: {
Nameserver: nsExample1,
Status: resolver.StatusOK,
},
nsExample2: {
Nameserver: nsExample2,
Status: resolver.StatusOK,
},
nsExample3: {
Nameserver: nsExample3,
Status: resolver.StatusTimeout,
},
nsExample4: {
Nameserver: nsExample4,
Status: resolver.StatusError,
},
}
assert.Equal(
t, 2, countStatus(results, resolver.StatusOK),
)
assert.Equal(
t, 0, countStatus(results, resolver.StatusNXDomain),
)
// Two of four answered, which is short of the quorum of
// three: this is the state that triggers a retry rather
// than an assertion failure.
assert.Equal(t, 2, answeredCount(results))
assert.Less(t, answeredCount(results), liveQuorum(len(results)))
assert.Equal(
t,
"ns1.example.=ok ns2.example.=ok "+
"ns3.example.=timeout ns4.example.=error",
describeStatuses(results),
)
}
// TestUnsanctionedStatusesRejectsWrongAnswers is the regression test
// for the defect this allowlist exists to prevent: a minority of
// nameservers answering WRONGLY while quorum keeps the suite green.
// nodata is the case that motivated it — it is a wrong answer, not
// silence, and it was previously banned by neither test.
func TestUnsanctionedStatusesRejectsWrongAnswers(t *testing.T) {
t.Parallel()
// Four nameservers, three OK and one answering nodata: a
// quorum of three is satisfied and no NXDOMAIN is present, so
// the old blocklist assertions both passed on this input.
results := map[string]*resolver.NameserverResponse{
nsExample1: {
Nameserver: nsExample1,
Status: resolver.StatusOK,
},
nsExample2: {
Nameserver: nsExample2,
Status: resolver.StatusOK,
},
nsExample3: {
Nameserver: nsExample3,
Status: resolver.StatusOK,
},
nsExample4: {
Nameserver: nsExample4,
Status: resolver.StatusNoData,
},
}
assert.GreaterOrEqual(
t,
countStatus(results, resolver.StatusOK),
liveQuorum(len(results)),
)
assert.Zero(t, countStatus(results, resolver.StatusNXDomain))
// nodata is an ANSWER, so it never triggers a retry: nothing
// but the allowlist stands between it and a false green.
assert.Equal(t, len(results), answeredCount(results))
assert.Equal(
t,
[]string{nsExample4 + "=nodata"},
unsanctionedStatuses(
results,
resolver.StatusOK,
resolver.StatusTimeout,
resolver.StatusError,
),
"nodata must be reported as an unsanctioned status",
)
}
func TestUnsanctionedStatusesToleratesSilenceOnly(t *testing.T) {
t.Parallel()
results := map[string]*resolver.NameserverResponse{
nsExample1: {
Nameserver: nsExample1,
Status: resolver.StatusNXDomain,
},
nsExample2: {
Nameserver: nsExample2,
Status: resolver.StatusTimeout,
},
nsExample3: {
Nameserver: nsExample3,
Status: resolver.StatusError,
},
}
allowed := []string{
resolver.StatusNXDomain,
resolver.StatusTimeout,
resolver.StatusError,
}
assert.Empty(
t,
unsanctionedStatuses(results, allowed...),
"timeout and error are non-answers and are tolerated",
)
// The same silent nameservers do not count towards a quorum.
assert.Equal(t, 1, answeredCount(results))
// An unknown status is treated as silence by answeredCount —
// so it retries and fails loudly — and is unsanctioned by the
// allowlist rather than quietly permitted.
const laterStatus = "some-status-added-later"
results[nsExample4] = &resolver.NameserverResponse{
Nameserver: nsExample4,
Status: laterStatus,
}
assert.Equal(t, 1, answeredCount(results))
assert.Equal(
t,
[]string{nsExample4 + "=" + laterStatus},
unsanctionedStatuses(results, allowed...),
)
}
internal/resolver/livedns_test.go
-385
View File
@@ -1,385 +0,0 @@
package resolver_test
import (
"context"
"errors"
"fmt"
"slices"
"sort"
"strings"
"testing"
"sneak.berlin/go/dnswatcher/internal/livednstest"
"sneak.berlin/go/dnswatcher/internal/resolver"
)
// ----------------------------------------------------------------
// Live DNS test support
// ----------------------------------------------------------------
//
// Tests that look something up in DNS query live DNS servers, never a
// stand-in; logic that works on record data may be tested on that
// data with no lookup (see TESTING.md). Each live operation below goes
// through livednstest.Retry, which bounds how many resolutions are in
// flight at once and retries an operation that got no answer (see
// package livednstest).
//
// Where an assertion spans several independent nameservers, a quorum
// is enough: a strict majority answering as expected. A server that
// fails to answer is tolerated, while a server that answers *wrongly*
// still fails the test.
//
// That tolerance is expressed as an ALLOWLIST of sanctioned statuses,
// never as a blocklist of known-bad ones. A blocklist bans the one
// wrong answer its author thought of and silently admits every other
// status, including any added to the resolver later; an allowlist
// fails on anything nobody explicitly sanctioned. Silence (timeout,
// error) is the only thing quorum exists to tolerate. A *wrong
// answer* — nxdomain for a name that exists, ok for one that does
// not, nodata for either — is never tolerated at any count.
// minNameservers is the smallest nameserver count a well-run zone is
// expected to publish.
const minNameservers = 2
// errLiveNoQuorum reports that too few of a domain's nameservers
// answered for a quorum assertion to be made.
var errLiveNoQuorum = errors.New("no nameserver quorum")
// liveQuorum is how many of total nameservers must agree for a
// multi-nameserver assertion to hold: a strict majority.
func liveQuorum(total int) int {
if total < 1 {
return 1
}
return total/2 + 1
}
// countStatus counts the responses carrying the given status.
func countStatus(
results map[string]*resolver.NameserverResponse,
status string,
) int {
n := 0
for _, resp := range results {
if resp.Status == status {
n++
}
}
return n
}
// liveAnswerStatuses is the closed set of statuses that count as a
// nameserver having ANSWERED at all, whether or not the test agrees
// with the answer. It is deliberately an allowlist: a status added
// to the resolver later is treated as silence, so it can only ever
// cause a retry and then a loud failure, never a quiet pass.
func liveAnswerStatuses() []string {
return []string{
resolver.StatusOK,
resolver.StatusNXDomain,
resolver.StatusNoData,
}
}
// answeredCount counts the nameservers that produced an answer of
// any kind, as opposed to failing or timing out.
func answeredCount(
results map[string]*resolver.NameserverResponse,
) int {
answers := liveAnswerStatuses()
n := 0
for _, resp := range results {
if slices.Contains(answers, resp.Status) {
n++
}
}
return n
}
// unsanctionedStatuses returns "nameserver=status" for every result
// whose status the caller did not explicitly sanction, sorted for a
// stable failure message. Callers pass the full closed set they will
// accept — the expected answer plus whichever non-answers (timeout,
// error) quorum is allowed to tolerate — so that any status outside
// it fails the test by name.
func unsanctionedStatuses(
results map[string]*resolver.NameserverResponse,
allowed ...string,
) []string {
offenders := make([]string, 0, len(results))
for ns, resp := range results {
if slices.Contains(allowed, resp.Status) {
continue
}
offenders = append(
offenders, fmt.Sprintf("%s=%s", ns, resp.Status),
)
}
sort.Strings(offenders)
return offenders
}
// describeStatuses renders per-nameserver statuses for use in
// assertion failure messages.
func describeStatuses(
results map[string]*resolver.NameserverResponse,
) string {
parts := make([]string, 0, len(results))
for ns, resp := range results {
parts = append(
parts, fmt.Sprintf("%s=%s", ns, resp.Status),
)
}
sort.Strings(parts)
return strings.Join(parts, " ")
}
// ----------------------------------------------------------------
// Live operation wrappers
// ----------------------------------------------------------------
// liveFindAuthoritative resolves a domain's authoritative
// nameservers, retrying until the delegation chain can be walked.
func liveFindAuthoritative(
t *testing.T,
r *resolver.Resolver,
domain string,
) []string {
t.Helper()
var out []string
livednstest.Retry(
t,
"FindAuthoritativeNameservers("+domain+")",
func(ctx context.Context) error {
ns, err := r.FindAuthoritativeNameservers(ctx, domain)
if err != nil {
return err
}
if len(ns) == 0 {
return fmt.Errorf(
"%w: %s has no nameservers",
livednstest.ErrNoAnswer, domain,
)
}
out = ns
return nil
},
)
return out
}
// liveLookupNS is liveFindAuthoritative through the LookupNS entry
// point, so that both entry points stay independently exercised.
func liveLookupNS(
t *testing.T,
r *resolver.Resolver,
domain string,
) []string {
t.Helper()
var out []string
livednstest.Retry(
t,
"LookupNS("+domain+")",
func(ctx context.Context) error {
ns, err := r.LookupNS(ctx, domain)
if err != nil {
return err
}
if len(ns) == 0 {
return fmt.Errorf(
"%w: %s has no nameservers",
livednstest.ErrNoAnswer, domain,
)
}
out = ns
return nil
},
)
return out
}
// liveQueryNameserver queries one nameserver, retrying while that
// nameserver fails to answer. NXDOMAIN and NODATA are answers and
// are returned to the caller to assert on.
func liveQueryNameserver(
t *testing.T,
r *resolver.Resolver,
nameserver string,
hostname string,
) *resolver.NameserverResponse {
t.Helper()
what := fmt.Sprintf(
"QueryNameserver(%s, %s)", nameserver, hostname,
)
var out *resolver.NameserverResponse
livednstest.Retry(
t,
what,
func(ctx context.Context) error {
resp, err := r.QueryNameserver(
ctx, nameserver, hostname,
)
if err != nil {
return err
}
if resp.Status == resolver.StatusTimeout ||
resp.Status == resolver.StatusError {
return fmt.Errorf(
"%w: %s returned %s: %s",
livednstest.ErrNoAnswer, nameserver,
resp.Status, resp.Error,
)
}
out = resp
return nil
},
)
return out
}
// liveQueryAllNameservers queries every authoritative nameserver
// for a hostname, retrying until a quorum of them has answered.
// Individual nameservers that stay silent are left in the result
// for the caller to account for.
func liveQueryAllNameservers(
t *testing.T,
r *resolver.Resolver,
hostname string,
) map[string]*resolver.NameserverResponse {
t.Helper()
var out map[string]*resolver.NameserverResponse
livednstest.Retry(
t,
"QueryAllNameservers("+hostname+")",
func(ctx context.Context) error {
results, err := r.QueryAllNameservers(ctx, hostname)
if err != nil {
return err
}
if len(results) == 0 {
return fmt.Errorf(
"%w: no nameservers queried for %s",
livednstest.ErrNoAnswer, hostname,
)
}
answered := answeredCount(results)
if answered < liveQuorum(len(results)) {
return fmt.Errorf(
"%w: %d of %d answered: %s",
errLiveNoQuorum, answered,
len(results), describeStatuses(results),
)
}
out = results
return nil
},
)
return out
}
// liveResolveIPs resolves a hostname that is expected to have
// addresses, retrying until at least one is returned.
func liveResolveIPs(
t *testing.T,
r *resolver.Resolver,
hostname string,
) []string {
t.Helper()
var out []string
livednstest.Retry(
t,
"ResolveIPAddresses("+hostname+")",
func(ctx context.Context) error {
ips, err := r.ResolveIPAddresses(ctx, hostname)
if err != nil {
return err
}
if len(ips) == 0 {
return fmt.Errorf(
"%w: no addresses for %s",
livednstest.ErrNoAnswer, hostname,
)
}
out = ips
return nil
},
)
return out
}
// liveResolveIPsAllowingEmpty resolves a hostname that may legitimately
// have no addresses, so the empty result is returned rather than
// retried. Used for names that must not exist; the corresponding
// QueryAllNameservers test is what proves the nameservers actively
// said NXDOMAIN rather than merely staying silent.
func liveResolveIPsAllowingEmpty(
t *testing.T,
r *resolver.Resolver,
hostname string,
) []string {
t.Helper()
var out []string
livednstest.Retry(
t,
"ResolveIPAddresses("+hostname+")",
func(ctx context.Context) error {
ips, err := r.ResolveIPAddresses(ctx, hostname)
if err != nil {
return err
}
out = ips
return nil
},
)
return out
}
internal/resolver/resolver.go
+13
View File
@@ -67,4 +67,17 @@ func NewFromLogger(log *slog.Logger) *Resolver {
}
}
// NewFromLoggerWithClient creates a Resolver with a custom DNS
// client, useful for testing with mock DNS responses.
func NewFromLoggerWithClient(
log *slog.Logger,
client DNSClient,
) *Resolver {
return &Resolver{
log: log,
client: client,
tcp: client,
}
}
// Method implementations are in iterative.go.
internal/resolver/resolver_test.go
+236 -107
View File
@@ -10,6 +10,7 @@ import (
"testing"
"time"
"github.com/miekg/dns"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
@@ -31,17 +32,32 @@ func newTestResolver(t *testing.T) *resolver.Resolver {
return resolver.NewFromLogger(log)
}
// findOneNSForDomain picks one authoritative nameserver to aim a
// test at. Quorum handling lives in livedns_test.go, and the live-DNS
// retry and concurrency limit in package livednstest.
func testContext(t *testing.T) context.Context {
t.Helper()
ctx, cancel := context.WithTimeout(
context.Background(), 60*time.Second,
)
t.Cleanup(cancel)
return ctx
}
func findOneNSForDomain(
t *testing.T,
r *resolver.Resolver,
ctx context.Context, //nolint:revive // test helper
domain string,
) string {
t.Helper()
return liveFindAuthoritative(t, r, domain)[0]
nameservers, err := r.FindAuthoritativeNameservers(
ctx, domain,
)
require.NoError(t, err)
require.NotEmpty(t, nameservers)
return nameservers[0]
}
// ----------------------------------------------------------------
@@ -54,7 +70,13 @@ func TestFindAuthoritativeNameservers_ValidDomain(
t.Parallel()
r := newTestResolver(t)
nameservers := liveFindAuthoritative(t, r, "google.com")
ctx := testContext(t)
nameservers, err := r.FindAuthoritativeNameservers(
ctx, "google.com",
)
require.NoError(t, err)
require.NotEmpty(t, nameservers)
hasGoogleNS := false
@@ -77,9 +99,13 @@ func TestFindAuthoritativeNameservers_Subdomain(
t.Parallel()
r := newTestResolver(t)
nameservers := liveFindAuthoritative(t, r, "www.google.com")
ctx := testContext(t)
assert.NotEmpty(t, nameservers)
nameservers, err := r.FindAuthoritativeNameservers(
ctx, "www.google.com",
)
require.NoError(t, err)
require.NotEmpty(t, nameservers)
}
func TestFindAuthoritativeNameservers_ReturnsSorted(
@@ -88,7 +114,12 @@ func TestFindAuthoritativeNameservers_ReturnsSorted(
t.Parallel()
r := newTestResolver(t)
nameservers := liveFindAuthoritative(t, r, "google.com")
ctx := testContext(t)
nameservers, err := r.FindAuthoritativeNameservers(
ctx, "google.com",
)
require.NoError(t, err)
assert.True(
t,
@@ -103,8 +134,17 @@ func TestFindAuthoritativeNameservers_Deterministic(
t.Parallel()
r := newTestResolver(t)
first := liveFindAuthoritative(t, r, "google.com")
second := liveFindAuthoritative(t, r, "google.com")
ctx := testContext(t)
first, err := r.FindAuthoritativeNameservers(
ctx, "google.com",
)
require.NoError(t, err)
second, err := r.FindAuthoritativeNameservers(
ctx, "google.com",
)
require.NoError(t, err)
assert.Equal(t, first, second)
}
@@ -115,8 +155,17 @@ func TestFindAuthoritativeNameservers_TrailingDot(
t.Parallel()
r := newTestResolver(t)
ns1 := liveFindAuthoritative(t, r, "google.com")
ns2 := liveFindAuthoritative(t, r, "google.com.")
ctx := testContext(t)
ns1, err := r.FindAuthoritativeNameservers(
ctx, "google.com",
)
require.NoError(t, err)
ns2, err := r.FindAuthoritativeNameservers(
ctx, "google.com.",
)
require.NoError(t, err)
assert.Equal(t, ns1, ns2)
}
@@ -127,7 +176,13 @@ func TestFindAuthoritativeNameservers_CloudflareDomain(
t.Parallel()
r := newTestResolver(t)
nameservers := liveFindAuthoritative(t, r, "cloudflare.com")
ctx := testContext(t)
nameservers, err := r.FindAuthoritativeNameservers(
ctx, "cloudflare.com",
)
require.NoError(t, err)
require.NotEmpty(t, nameservers)
for _, ns := range nameservers {
assert.True(t, strings.HasSuffix(ns, "."),
@@ -144,9 +199,13 @@ func TestQueryNameserver_BasicA(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
ns := findOneNSForDomain(t, r, "google.com")
resp := liveQueryNameserver(t, r, ns, "www.google.com")
ctx := testContext(t)
ns := findOneNSForDomain(t, r, ctx, "google.com")
resp, err := r.QueryNameserver(
ctx, ns, "www.google.com",
)
require.NoError(t, err)
require.NotNil(t, resp)
assert.Equal(t, resolver.StatusOK, resp.Status)
@@ -163,8 +222,13 @@ func TestQueryNameserver_AAAA(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
ns := findOneNSForDomain(t, r, "cloudflare.com")
resp := liveQueryNameserver(t, r, ns, "cloudflare.com")
ctx := testContext(t)
ns := findOneNSForDomain(t, r, ctx, "cloudflare.com")
resp, err := r.QueryNameserver(
ctx, ns, "cloudflare.com",
)
require.NoError(t, err)
aaaaRecords := resp.Records["AAAA"]
require.NotEmpty(t, aaaaRecords,
@@ -183,8 +247,13 @@ func TestQueryNameserver_MX(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
ns := findOneNSForDomain(t, r, "google.com")
resp := liveQueryNameserver(t, r, ns, "google.com")
ctx := testContext(t)
ns := findOneNSForDomain(t, r, ctx, "google.com")
resp, err := r.QueryNameserver(
ctx, ns, "google.com",
)
require.NoError(t, err)
mxRecords := resp.Records["MX"]
require.NotEmpty(t, mxRecords,
@@ -196,8 +265,13 @@ func TestQueryNameserver_TXT(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
ns := findOneNSForDomain(t, r, "google.com")
resp := liveQueryNameserver(t, r, ns, "google.com")
ctx := testContext(t)
ns := findOneNSForDomain(t, r, ctx, "google.com")
resp, err := r.QueryNameserver(
ctx, ns, "google.com",
)
require.NoError(t, err)
txtRecords := resp.Records["TXT"]
require.NotEmpty(t, txtRecords,
@@ -223,10 +297,14 @@ func TestQueryNameserver_NXDomain(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
ns := findOneNSForDomain(t, r, "google.com")
resp := liveQueryNameserver(
t, r, ns, "this-surely-does-not-exist-xyz.google.com",
ctx := testContext(t)
ns := findOneNSForDomain(t, r, ctx, "google.com")
resp, err := r.QueryNameserver(
ctx, ns,
"this-surely-does-not-exist-xyz.google.com",
)
require.NoError(t, err)
assert.Equal(t, resolver.StatusNXDomain, resp.Status)
}
@@ -235,8 +313,13 @@ func TestQueryNameserver_RecordsSorted(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
ns := findOneNSForDomain(t, r, "google.com")
resp := liveQueryNameserver(t, r, ns, "google.com")
ctx := testContext(t)
ns := findOneNSForDomain(t, r, ctx, "google.com")
resp, err := r.QueryNameserver(
ctx, ns, "google.com",
)
require.NoError(t, err)
for recordType, values := range resp.Records {
assert.True(
@@ -253,8 +336,13 @@ func TestQueryNameserver_ResponseIncludesNameserver(
t.Parallel()
r := newTestResolver(t)
ns := findOneNSForDomain(t, r, "cloudflare.com")
resp := liveQueryNameserver(t, r, ns, "cloudflare.com")
ctx := testContext(t)
ns := findOneNSForDomain(t, r, ctx, "cloudflare.com")
resp, err := r.QueryNameserver(
ctx, ns, "cloudflare.com",
)
require.NoError(t, err)
assert.Equal(t, ns, resp.Nameserver)
}
@@ -265,10 +353,14 @@ func TestQueryNameserver_EmptyRecordsOnNXDomain(
t.Parallel()
r := newTestResolver(t)
ns := findOneNSForDomain(t, r, "google.com")
resp := liveQueryNameserver(
t, r, ns, "this-surely-does-not-exist-xyz.google.com",
ctx := testContext(t)
ns := findOneNSForDomain(t, r, ctx, "google.com")
resp, err := r.QueryNameserver(
ctx, ns,
"this-surely-does-not-exist-xyz.google.com",
)
require.NoError(t, err)
totalRecords := 0
for _, values := range resp.Records {
@@ -282,9 +374,18 @@ func TestQueryNameserver_TrailingDotHandling(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
ns := findOneNSForDomain(t, r, "google.com")
resp1 := liveQueryNameserver(t, r, ns, "google.com")
resp2 := liveQueryNameserver(t, r, ns, "google.com.")
ctx := testContext(t)
ns := findOneNSForDomain(t, r, ctx, "google.com")
resp1, err := r.QueryNameserver(
ctx, ns, "google.com",
)
require.NoError(t, err)
resp2, err := r.QueryNameserver(
ctx, ns, "google.com.",
)
require.NoError(t, err)
assert.Equal(t, resp1.Status, resp2.Status)
}
@@ -297,9 +398,15 @@ func TestQueryAllNameservers_ReturnsAllNS(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
results := liveQueryAllNameservers(t, r, "google.com")
ctx := testContext(t)
assert.GreaterOrEqual(t, len(results), minNameservers)
results, err := r.QueryAllNameservers(
ctx, "google.com",
)
require.NoError(t, err)
require.NotEmpty(t, results)
assert.GreaterOrEqual(t, len(results), 2)
for ns, resp := range results {
assert.Equal(t, ns, resp.Nameserver)
@@ -310,36 +417,19 @@ func TestQueryAllNameservers_AllReturnOK(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
results := liveQueryAllNameservers(t, r, "google.com")
ctx := testContext(t)
// A quorum, not unanimity: one authoritative server being
// slow or rate-limiting us is a property of the live
// internet, not a resolver defect.
assert.GreaterOrEqual(
t,
countStatus(results, resolver.StatusOK),
liveQuorum(len(results)),
"a quorum of nameservers should answer OK: %s",
describeStatuses(results),
results, err := r.QueryAllNameservers(
ctx, "google.com",
)
require.NoError(t, err)
// Quorum tolerates SILENCE only. Every individual result must
// be either the expected answer or a non-answer: ok, timeout
// or error, and nothing else. Stated as a closed allowlist so
// that a wrong answer no one thought to ban — nxdomain and
// nodata today, any status added later — fails here rather
// than sliding through under the quorum.
assert.Empty(
t,
unsanctionedStatuses(
results,
resolver.StatusOK,
resolver.StatusTimeout,
resolver.StatusError,
),
"every nameserver must answer OK or not answer at all: %s",
describeStatuses(results),
)
for ns, resp := range results {
assert.Equal(
t, resolver.StatusOK, resp.Status,
"NS %s should return OK", ns,
)
}
}
func TestQueryAllNameservers_NXDomainFromAllNS(
@@ -348,34 +438,20 @@ func TestQueryAllNameservers_NXDomainFromAllNS(
t.Parallel()
r := newTestResolver(t)
results := liveQueryAllNameservers(
t, r, "this-surely-does-not-exist-xyz.google.com",
)
ctx := testContext(t)
assert.GreaterOrEqual(
t,
countStatus(results, resolver.StatusNXDomain),
liveQuorum(len(results)),
"a quorum of nameservers should report NXDOMAIN: %s",
describeStatuses(results),
results, err := r.QueryAllNameservers(
ctx,
"this-surely-does-not-exist-xyz.google.com",
)
require.NoError(t, err)
// Silence is tolerated; any actual answer other than NXDOMAIN
// is not. Closed allowlist for the same reason as above: a
// server answering `ok` or `nodata` for a name that must not
// exist is a wrong answer, not a slow one.
assert.Empty(
t,
unsanctionedStatuses(
results,
resolver.StatusNXDomain,
resolver.StatusTimeout,
resolver.StatusError,
),
"every nameserver must report NXDOMAIN or not answer "+
"at all: %s",
describeStatuses(results),
)
for ns, resp := range results {
assert.Equal(
t, resolver.StatusNXDomain, resp.Status,
"NS %s should return nxdomain", ns,
)
}
}
// ----------------------------------------------------------------
@@ -386,7 +462,11 @@ func TestLookupNS_ValidDomain(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
nameservers := liveLookupNS(t, r, "google.com")
ctx := testContext(t)
nameservers, err := r.LookupNS(ctx, "google.com")
require.NoError(t, err)
require.NotEmpty(t, nameservers)
for _, ns := range nameservers {
assert.True(t, strings.HasSuffix(ns, "."),
@@ -399,7 +479,10 @@ func TestLookupNS_Sorted(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
nameservers := liveLookupNS(t, r, "google.com")
ctx := testContext(t)
nameservers, err := r.LookupNS(ctx, "google.com")
require.NoError(t, err)
assert.True(t, sort.StringsAreSorted(nameservers))
}
@@ -408,8 +491,15 @@ func TestLookupNS_MatchesFindAuthoritative(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
fromLookup := liveLookupNS(t, r, "google.com")
fromFind := liveFindAuthoritative(t, r, "google.com")
ctx := testContext(t)
fromLookup, err := r.LookupNS(ctx, "google.com")
require.NoError(t, err)
fromFind, err := r.FindAuthoritativeNameservers(
ctx, "google.com",
)
require.NoError(t, err)
assert.Equal(t, fromFind, fromLookup)
}
@@ -422,7 +512,11 @@ func TestResolveIPAddresses_ReturnsIPs(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
ips := liveResolveIPs(t, r, "google.com")
ctx := testContext(t)
ips, err := r.ResolveIPAddresses(ctx, "google.com")
require.NoError(t, err)
require.NotEmpty(t, ips)
for _, ip := range ips {
parsed := net.ParseIP(ip)
@@ -436,7 +530,10 @@ func TestResolveIPAddresses_Deduplicated(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
ips := liveResolveIPs(t, r, "google.com")
ctx := testContext(t)
ips, err := r.ResolveIPAddresses(ctx, "google.com")
require.NoError(t, err)
seen := make(map[string]bool)
@@ -450,7 +547,10 @@ func TestResolveIPAddresses_Sorted(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
ips := liveResolveIPs(t, r, "google.com")
ctx := testContext(t)
ips, err := r.ResolveIPAddresses(ctx, "google.com")
require.NoError(t, err)
assert.True(t, sort.StringsAreSorted(ips))
}
@@ -461,10 +561,13 @@ func TestResolveIPAddresses_NXDomainReturnsEmpty(
t.Parallel()
r := newTestResolver(t)
ips := liveResolveIPsAllowingEmpty(
t, r, "this-surely-does-not-exist-xyz.google.com",
)
ctx := testContext(t)
ips, err := r.ResolveIPAddresses(
ctx,
"this-surely-does-not-exist-xyz.google.com",
)
require.NoError(t, err)
assert.Empty(t, ips)
}
@@ -472,9 +575,11 @@ func TestResolveIPAddresses_CloudflareDomain(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
ips := liveResolveIPs(t, r, "cloudflare.com")
ctx := testContext(t)
assert.NotEmpty(t, ips)
ips, err := r.ResolveIPAddresses(ctx, "cloudflare.com")
require.NoError(t, err)
require.NotEmpty(t, ips)
}
// ----------------------------------------------------------------
@@ -525,18 +630,21 @@ func TestQueryAllNameservers_ContextCanceled(t *testing.T) {
func TestQueryNameserverIP_Timeout(t *testing.T) {
t.Parallel()
r := newTestResolver(t)
log := slog.New(slog.NewTextHandler(
os.Stderr,
&slog.HandlerOptions{Level: slog.LevelDebug},
))
r := resolver.NewFromLoggerWithClient(
log, &timeoutClient{},
)
// Nothing answers at 192.0.2.1, a documentation address. The
// resolver tries each query twice, and the first try gives up
// after two seconds. A deadline that ends during the first try
// makes the status vary from run to run between nodata and
// timeout, so the deadline must outlast the first try.
ctx, cancel := context.WithTimeout(
context.Background(), 3*time.Second,
context.Background(), 10*time.Second,
)
t.Cleanup(cancel)
// Query any IP — the client always returns a timeout error.
resp, err := r.QueryNameserverIP(
ctx, "unreachable.test.", "192.0.2.1",
"example.com",
@@ -547,6 +655,27 @@ func TestQueryNameserverIP_Timeout(t *testing.T) {
assert.NotEmpty(t, resp.Error)
}
// timeoutClient simulates DNS timeout errors for testing.
type timeoutClient struct{}
func (c *timeoutClient) ExchangeContext(
_ context.Context,
_ *dns.Msg,
_ string,
) (*dns.Msg, time.Duration, error) {
return nil, 0, &net.OpError{
Op: "read",
Net: "udp",
Err: &timeoutError{},
}
}
type timeoutError struct{}
func (e *timeoutError) Error() string { return "i/o timeout" }
func (e *timeoutError) Timeout() bool { return true }
func (e *timeoutError) Temporary() bool { return true }
func TestResolveIPAddresses_ContextCanceled(t *testing.T) {
t.Parallel()
internal/server/export_test.go
-24
View File
@@ -1,24 +0,0 @@
package server
import (
"net/http"
"time"
)
// RequestTimeout exports the handler execution budget applied by
// chimw.Timeout in SetupRoutes, so tests can assert the relationship
// between it and the server's WriteTimeout.
const RequestTimeout time.Duration = requestTimeout
// SetListenPort overrides the port Run binds. A test uses it to hand
// Run an unbindable port so ListenAndServe fails immediately and Run
// returns after storing its http.Server.
func SetListenPort(s *Server, port int) {
s.port = port
}
// HTTPServerOf returns the http.Server that Run built and stored, so a
// test can inspect the timeouts the running server actually carries.
func HTTPServerOf(s *Server) *http.Server {
return s.httpServer
}
internal/server/routes.go
+1 -23
View File
@@ -1,14 +1,11 @@
package server
import (
"net/http"
"time"
"github.com/go-chi/chi/v5"
chimw "github.com/go-chi/chi/v5/middleware"
"github.com/prometheus/client_golang/prometheus/promhttp"
"sneak.berlin/go/dnswatcher/static"
)
// requestTimeout is the maximum duration for handling a request.
@@ -21,30 +18,11 @@ func (s *Server) SetupRoutes() {
// Global middleware
s.router.Use(chimw.Recoverer)
s.router.Use(chimw.RequestID)
s.router.Use(s.mw.SecurityHeaders())
s.router.Use(s.mw.Logging())
s.router.Use(s.mw.CORS())
s.router.Use(chimw.Timeout(requestTimeout))
// Dashboard (read-only web UI)
s.router.Get("/", s.handlers.HandleDashboard())
// Static assets (embedded CSS/JS)
s.router.Mount(
"/s",
http.StripPrefix(
"/s",
http.FileServer(http.FS(static.Static)),
),
)
// Health check (standard well-known path)
s.router.Get(
"/.well-known/healthcheck",
s.handlers.HandleHealthCheck(),
)
// Legacy health check (keep for backward compatibility)
// Health check
s.router.Get("/health", s.handlers.HandleHealthCheck())
// API v1 routes
internal/server/server.go
+7 -64
View File
@@ -33,52 +33,8 @@ type Params struct {
// shutdownTimeout is how long to wait for graceful shutdown.
const shutdownTimeout = 30 * time.Second
// Socket-level timeouts for the HTTP server.
//
// These bound time spent on the connection itself and are a distinct
// control from the per-request handler budget enforced by
// chimw.Timeout(requestTimeout) in routes.go: that one cancels the
// request context after requestTimeout but never touches the socket,
// so without the values below a peer can hold a connection open
// forever (slowloris, unreaped keep-alives).
//
// The one hard constraint between the two controls is
// writeTimeout > requestTimeout. net/http arms the write deadline
// once the request headers have been read, so on a plaintext
// connection it covers handler execution AND the response flush. If
// writeTimeout were <= requestTimeout the server would sever the
// connection before a handler that legitimately consumed its full
// budget could emit anything, making the 60s budget unreachable in
// practice. The margin between them is the response-flush allowance.
//
// The only clients of this service are browsers loading the dashboard
// and a Prometheus scraper; the values are sized for those.
const (
// readHeaderTimeout is the max duration for reading request
// headers.
readHeaderTimeout = 10 * time.Second
// readTimeout bounds reading the entire request, headers plus
// body. Every route here is a GET with no body, so this only
// ever needs to cover headers; the extra 5s over
// readHeaderTimeout is slack, not a real allowance, and keeps a
// body dribbled one byte at a time from holding the read side
// open indefinitely.
readTimeout = 15 * time.Second
// writeTimeout must exceed the requestTimeout handler budget
// (60s) per the note above. The 15s difference is the allowance
// for flushing a completed response to a slow client.
writeTimeout = 75 * time.Second
// idleTimeout reaps keep-alive connections between requests. It
// is deliberately longer than the common Prometheus scrape
// intervals (15s/30s/60s) so the scraper reuses its connection
// rather than reconnecting every cycle, while a browser tab
// left open on the dashboard stops occupying a connection
// within two minutes of going quiet.
idleTimeout = 120 * time.Second
)
// readHeaderTimeout is the max duration for reading request headers.
const readHeaderTimeout = 10 * time.Second
// Server is the HTTP server.
type Server struct {
@@ -120,29 +76,16 @@ func New(
return srv, nil
}
// newHTTPServer builds the listening http.Server with every
// socket-level timeout set. All four are set deliberately: a zero
// value in net/http means "no limit", not "some default".
func newHTTPServer(
listenAddr string,
handler http.Handler,
) *http.Server {
return &http.Server{
Addr: listenAddr,
Handler: handler,
ReadTimeout: readTimeout,
ReadHeaderTimeout: readHeaderTimeout,
WriteTimeout: writeTimeout,
IdleTimeout: idleTimeout,
}
}
// Run starts the HTTP server.
func (s *Server) Run() {
s.SetupRoutes()
listenAddr := fmt.Sprintf(":%d", s.port)
s.httpServer = newHTTPServer(listenAddr, s)
s.httpServer = &http.Server{
Addr: listenAddr,
Handler: s,
ReadHeaderTimeout: readHeaderTimeout,
}
s.log.Info("http server starting", "addr", listenAddr)
internal/server/server_test.go
-130
View File
@@ -1,130 +0,0 @@
package server_test
import (
"testing"
"github.com/spf13/viper"
"go.uber.org/fx"
"sneak.berlin/go/dnswatcher/internal/config"
"sneak.berlin/go/dnswatcher/internal/globals"
"sneak.berlin/go/dnswatcher/internal/handlers"
"sneak.berlin/go/dnswatcher/internal/healthcheck"
"sneak.berlin/go/dnswatcher/internal/logger"
"sneak.berlin/go/dnswatcher/internal/middleware"
"sneak.berlin/go/dnswatcher/internal/notify"
"sneak.berlin/go/dnswatcher/internal/server"
"sneak.berlin/go/dnswatcher/internal/state"
)
// buildServer wires a *server.Server exactly as cmd/dnswatcher does,
// minus the watcher/resolver subtree that would touch live DNS. fx
// builds the object graph but the lifecycle is never started, so no
// OnStart hook runs and nothing listens or resolves. The caller must
// first configure viper (config.New reads it), which is also why the
// caller cannot run in parallel.
func buildServer(t *testing.T) *server.Server {
t.Helper()
var srv *server.Server
app := fx.New(
fx.NopLogger,
fx.Provide(
globals.New,
logger.New,
config.New,
state.New,
healthcheck.New,
notify.New,
middleware.New,
handlers.New,
server.New,
),
fx.Populate(&srv),
)
err := app.Err()
if err != nil {
t.Fatalf("building server graph: %v", err)
}
return srv
}
// TestRunWiresSocketTimeouts pins that the http.Server the running
// server actually serves — the one Run builds and hands to
// ListenAndServe — carries every socket-level timeout, plus the two
// relationships the values must satisfy.
//
// Run is driven to completion with an unbindable port: it builds and
// stores s.httpServer, then ListenAndServe fails at once and Run
// returns without ever listening. The assertions run in the same
// goroutine after Run returns, so reading s.httpServer is free of any
// data race. Nothing here measures elapsed time.
//
// ReadTimeout must be at least ReadHeaderTimeout. net/http reads the
// headers under ReadHeaderTimeout, then sets the read deadline for the
// rest of the request to ReadTimeout, counted from when it started
// reading the request. If ReadTimeout were smaller, a request whose
// headers arrived after ReadTimeout but within ReadHeaderTimeout would
// get a read deadline that had already passed, so reading its body
// would fail at once.
func TestRunWiresSocketTimeouts(t *testing.T) {
// Sets an env var and touches viper global state, so like the
// config tests it cannot use t.Parallel.
viper.Reset()
t.Setenv("DNSWATCHER_TARGETS", "example.com")
srv := buildServer(t)
server.SetListenPort(srv, -1)
srv.Run()
hs := server.HTTPServerOf(srv)
if hs == nil {
t.Fatal("Run did not build an http.Server")
}
if hs.ReadTimeout <= 0 {
t.Errorf("ReadTimeout must be non-zero, got %v", hs.ReadTimeout)
}
if hs.ReadHeaderTimeout <= 0 {
t.Errorf(
"ReadHeaderTimeout must be non-zero, got %v",
hs.ReadHeaderTimeout,
)
}
if hs.WriteTimeout <= 0 {
t.Errorf("WriteTimeout must be non-zero, got %v", hs.WriteTimeout)
}
if hs.IdleTimeout <= 0 {
t.Errorf("IdleTimeout must be non-zero, got %v", hs.IdleTimeout)
}
if hs.WriteTimeout <= server.RequestTimeout {
t.Errorf(
"WriteTimeout (%v) must exceed handler budget (%v)",
hs.WriteTimeout,
server.RequestTimeout,
)
}
if hs.ReadTimeout < hs.ReadHeaderTimeout {
t.Errorf(
"ReadTimeout (%v) must be >= ReadHeaderTimeout (%v)",
hs.ReadTimeout,
hs.ReadHeaderTimeout,
)
}
if hs.Handler != srv {
t.Errorf(
"Run wired handler %T, want the *server.Server",
hs.Handler,
)
}
}
internal/state/state.go
-29
View File
@@ -148,11 +148,6 @@ func New(
lifecycle.Append(fx.Hook{
OnStart: func(_ context.Context) error {
err := state.checkDataDirWritable()
if err != nil {
return err
}
return state.Load()
},
OnStop: func(_ context.Context) error {
@@ -350,27 +345,3 @@ func (s *State) GetCertificateState(
return cs, ok
}
// checkDataDirWritable creates the data directory if needed, then writes
// and removes the temp file that Save uses. It runs at startup so that an
// unwritable directory stops the process, instead of the process running
// with every save failing and only logged.
func (s *State) checkDataDirWritable() error {
dir := s.config.DataDir
tmpPath := s.config.StatePath() + ".tmp"
err := os.MkdirAll(dir, dirPermissions)
if err == nil {
err = os.WriteFile(tmpPath, nil, filePermissions)
}
if err == nil {
err = os.Remove(tmpPath)
}
if err != nil {
return fmt.Errorf("data directory %s is not writable: %w", dir, err)
}
return nil
}
internal/state/state_test.go
-1421
View File
File diff suppressed because it is too large Load Diff
internal/state/state_test_helper.go
-16
View File
@@ -20,19 +20,3 @@ func NewForTest() *State {
config: &config.Config{DataDir: ""},
}
}
// NewForTestWithDataDir creates a State backed by the given directory
// for tests that need file persistence.
func NewForTestWithDataDir(dataDir string) *State {
return &State{
log: slog.Default(),
snapshot: &Snapshot{
Version: stateVersion,
Domains: make(map[string]*DomainState),
Hostnames: make(map[string]*HostnameState),
Ports: make(map[string]*PortState),
Certificates: make(map[string]*CertificateState),
},
config: &config.Config{DataDir: dataDir},
}
}
internal/watcher/export_test.go
-25
View File
@@ -1,25 +0,0 @@
package watcher
import (
"context"
"sneak.berlin/go/dnswatcher/internal/state"
)
// NewlyDisagreeingPairs exports newlyDisagreeingPairs for testing.
func NewlyDisagreeingPairs(
prev *state.HostnameState,
current map[string]map[string][]string,
) [][2]string {
return newlyDisagreeingPairs(prev, current)
}
// DetectHostnameChanges exports detectHostnameChanges for testing.
func (w *Watcher) DetectHostnameChanges(
ctx context.Context,
hostname string,
prev *state.HostnameState,
current map[string]map[string][]string,
) {
w.detectHostnameChanges(ctx, hostname, prev, current)
}
internal/watcher/inconsistency_test.go
-182
View File
@@ -1,182 +0,0 @@
package watcher_test
import (
"slices"
"testing"
"sneak.berlin/go/dnswatcher/internal/state"
"sneak.berlin/go/dnswatcher/internal/watcher"
)
const (
host = "www.example.net"
nsA = "a.ns.example.net."
nsB = "b.ns.example.net."
nsC = "c.ns.example.net."
ip1 = "192.0.2.1"
ip2 = "192.0.2.2"
ip3 = "192.0.2.3"
)
// hostnameState builds the state a check with these records leaves behind.
func hostnameState(
records map[string]map[string][]string,
) *state.HostnameState {
hs := &state.HostnameState{
RecordsByNameserver: make(map[string]*state.NameserverRecordState),
}
for ns, recs := range records {
hs.RecordsByNameserver[ns] = &state.NameserverRecordState{
Records: recs,
Status: "ok",
}
}
return hs
}
func TestNewlyDisagreeingPairs(t *testing.T) {
t.Parallel()
onlyA := map[string]map[string][]string{nsA: {"A": {ip1}}}
agree := map[string]map[string][]string{nsA: {"A": {ip1}}, nsB: {"A": {ip1}}}
disagree := map[string]map[string][]string{nsA: {"A": {ip1}}, nsB: {"A": {ip2}}}
alert := [][2]string{{nsA, nsB}}
// b already disagrees with a and c; then c changes, so a and c,
// which agreed, now differ.
bDiffers := map[string]map[string][]string{
nsA: {"A": {ip1}}, nsB: {"A": {ip2}}, nsC: {"A": {ip1}},
}
cChanges := map[string]map[string][]string{
nsA: {"A": {ip1}}, nsB: {"A": {ip2}}, nsC: {"A": {ip3}},
}
// Each case starts from the state loaded at startup and runs the
// checks in order; want[i] is what check i alerts for.
tests := []struct {
name string
loaded map[string]map[string][]string
checks []map[string]map[string][]string
want [][][2]string
}{
{
name: "disagreement persisting across checks alerts once",
loaded: agree,
checks: []map[string]map[string][]string{disagree, disagree, disagree},
want: [][][2]string{alert, nil, nil},
},
{
name: "disagreement starting on a later check alerts on it",
loaded: agree,
checks: []map[string]map[string][]string{agree, agree, disagree},
want: [][][2]string{nil, nil, alert},
},
{
name: "disagreement in the loaded state does not alert",
loaded: disagree,
checks: []map[string]map[string][]string{disagree, disagree},
want: [][][2]string{nil, nil},
},
{
name: "nameserver new on the first check and disagreeing alerts once",
loaded: onlyA,
checks: []map[string]map[string][]string{disagree, disagree},
want: [][][2]string{alert, nil},
},
{
name: "disagreement after agreeing again alerts again",
loaded: agree,
checks: []map[string]map[string][]string{disagree, agree, disagree},
want: [][][2]string{alert, nil, alert},
},
{
name: "new disagreement while another nameserver differs alerts",
loaded: bDiffers,
checks: []map[string]map[string][]string{cChanges, cChanges},
want: [][][2]string{{{nsA, nsC}}, nil},
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
prev := hostnameState(tt.loaded)
for i, current := range tt.checks {
got := watcher.NewlyDisagreeingPairs(prev, current)
if !slices.Equal(got, tt.want[i]) {
t.Errorf(
"check %d: alerted for %v, want %v",
i, got, tt.want[i],
)
}
prev = hostnameState(current)
}
})
}
}
func TestInconsistencyAlert(t *testing.T) {
t.Parallel()
onlyA := map[string]map[string][]string{nsA: {"A": {ip1}}}
agree := map[string]map[string][]string{nsA: {"A": {ip1}}, nsB: {"A": {ip1}}}
disagree := map[string]map[string][]string{nsA: {"A": {ip1}}, nsB: {"A": {ip2}}}
// Each case starts from the state loaded at startup and then sees
// the nameservers disagree on three checks in a row.
tests := []struct {
name string
loaded map[string]map[string][]string
want int
}{
{
name: "disagreement lasting several checks alerts once",
loaded: agree,
want: 1,
},
{
name: "disagreement in the loaded state does not alert",
loaded: disagree,
want: 0,
},
{
name: "nameserver new on the first check and disagreeing alerts once",
loaded: onlyA,
want: 1,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
// The hostname change detection uses only the notifier.
notifier := &mockNotifier{}
w := watcher.NewForTest(nil, nil, nil, nil, nil, notifier)
prev := hostnameState(tt.loaded)
for range 3 {
w.DetectHostnameChanges(t.Context(), host, prev, disagree)
prev = hostnameState(disagree)
}
got := 0
for _, n := range notifier.getNotifications() {
if n.Title == "Inconsistency: "+host {
got++
}
}
if got != tt.want {
t.Errorf("sent %d inconsistency alerts, want %d", got, tt.want)
}
})
}
}
internal/watcher/watcher.go
+22 -87
View File
@@ -26,12 +26,6 @@ const tlsPort = 443
// hoursPerDay converts days to hours for duration calculations.
const hoursPerDay = 24
// Status values recorded for nameserver and certificate checks.
const (
statusOK = "ok"
statusError = "error"
)
// Params contains dependencies for Watcher.
type Params struct {
fx.In
@@ -135,7 +129,6 @@ func (w *Watcher) Run(ctx context.Context) {
)
w.RunOnce(ctx)
w.maybeSendTestNotification(ctx)
dnsTicker := time.NewTicker(w.config.DNSInterval)
tlsTicker := time.NewTicker(w.config.TLSInterval)
@@ -350,7 +343,7 @@ func buildHostnameState(
for ns, recs := range records {
hs.RecordsByNameserver[ns] = &state.NameserverRecordState{
Records: recs,
Status: statusOK,
Status: "ok",
LastChecked: now,
}
}
@@ -366,7 +359,7 @@ func (w *Watcher) detectHostnameChanges(
) {
w.detectRecordChanges(ctx, hostname, prev, current)
w.detectNSDisappearances(ctx, hostname, prev, current)
w.detectInconsistencies(ctx, hostname, prev, current)
w.detectInconsistencies(ctx, hostname, current)
}
func (w *Watcher) detectRecordChanges(
@@ -408,7 +401,7 @@ func (w *Watcher) detectNSDisappearances(
current map[string]map[string][]string,
) {
for ns, prevNS := range prev.RecordsByNameserver {
if _, ok := current[ns]; ok || prevNS.Status != statusOK {
if _, ok := current[ns]; ok || prevNS.Status != "ok" {
continue
}
@@ -427,7 +420,7 @@ func (w *Watcher) detectNSDisappearances(
for ns := range current {
prevNS, ok := prev.RecordsByNameserver[ns]
if !ok || prevNS.Status != statusError {
if !ok || prevNS.Status != "error" {
continue
}
@@ -448,11 +441,22 @@ func (w *Watcher) detectNSDisappearances(
func (w *Watcher) detectInconsistencies(
ctx context.Context,
hostname string,
prev *state.HostnameState,
current map[string]map[string][]string,
) {
for _, pair := range newlyDisagreeingPairs(prev, current) {
ns1, ns2 := pair[0], pair[1]
nameservers := make([]string, 0, len(current))
for ns := range current {
nameservers = append(nameservers, ns)
}
sort.Strings(nameservers)
for i := range len(nameservers) - 1 {
ns1 := nameservers[i]
ns2 := nameservers[i+1]
if recordsEqual(current[ns1], current[ns2]) {
continue
}
msg := fmt.Sprintf(
"Hostname: %s\n%s: %v\n%s: %v",
@@ -470,43 +474,6 @@ func (w *Watcher) detectInconsistencies(
}
}
// newlyDisagreeingPairs returns every pair of nameservers whose records
// differ in current, in sorted order of name, except pairs where both
// nameservers were in prev and already differed there. A nameserver
// missing from prev is paired with every nameserver it differs from.
func newlyDisagreeingPairs(
prev *state.HostnameState,
current map[string]map[string][]string,
) [][2]string {
nameservers := make([]string, 0, len(current))
for ns := range current {
nameservers = append(nameservers, ns)
}
sort.Strings(nameservers)
var pairs [][2]string
for i, ns1 := range nameservers {
for _, ns2 := range nameservers[i+1:] {
if recordsEqual(current[ns1], current[ns2]) {
continue
}
prev1, ok1 := prev.RecordsByNameserver[ns1]
prev2, ok2 := prev.RecordsByNameserver[ns2]
if ok1 && ok2 && !recordsEqual(prev1.Records, prev2.Records) {
continue
}
pairs = append(pairs, [2]string{ns1, ns2})
}
}
return pairs
}
func (w *Watcher) checkAllPorts(ctx context.Context) {
// Phase 1: Build current IP:port → hostname associations
// from fresh DNS data.
@@ -737,7 +704,7 @@ func (w *Watcher) handleTLSError(
now time.Time,
err error,
) {
if hasPrev && !w.firstRun && prev.Status == statusOK {
if hasPrev && !w.firstRun && prev.Status == "ok" {
msg := fmt.Sprintf(
"Host: %s\nIP: %s\nError: %s",
hostname, ip, err,
@@ -753,7 +720,7 @@ func (w *Watcher) handleTLSError(
w.state.SetCertificateState(
certKey, &state.CertificateState{
Status: statusError,
Status: "error",
Error: err.Error(),
LastChecked: now,
},
@@ -780,7 +747,7 @@ func (w *Watcher) handleTLSSuccess(
Issuer: cert.Issuer,
NotAfter: cert.NotAfter,
SubjectAlternativeNames: cert.SubjectAlternativeNames,
Status: statusOK,
Status: "ok",
LastChecked: now,
},
)
@@ -792,7 +759,7 @@ func (w *Watcher) detectTLSChanges(
prev *state.CertificateState,
cert *tlscheck.CertificateInfo,
) {
if prev.Status == statusError {
if prev.Status == "error" {
msg := fmt.Sprintf(
"Host: %s\nIP: %s\nTLS recovered",
hostname, ip,
@@ -887,38 +854,6 @@ func (w *Watcher) saveState() {
}
}
// maybeSendTestNotification sends a startup status notification
// after the first full scan completes, if SEND_TEST_NOTIFICATION
// is enabled. The message is clearly informational ("all ok")
// and not an error or anomaly alert.
func (w *Watcher) maybeSendTestNotification(ctx context.Context) {
if !w.config.SendTestNotification {
return
}
snap := w.state.GetSnapshot()
msg := fmt.Sprintf(
"dnswatcher has started and completed its initial scan.\n"+
"Monitoring %d domain(s) and %d hostname(s).\n"+
"Tracking %d port endpoint(s) and %d TLS certificate(s).\n"+
"All notification channels are working.",
len(snap.Domains),
len(snap.Hostnames),
len(snap.Ports),
len(snap.Certificates),
)
w.log.Info("sending startup test notification")
w.notify.SendNotification(
ctx,
"✅ dnswatcher startup complete",
msg,
"success",
)
}
// --- Utility functions ---
func toSet(items []string) map[string]bool {
internal/watcher/watcher_test.go
+475 -368
View File
File diff suppressed because it is too large Load Diff
script/bootstrap
-90
View File
@@ -1,90 +0,0 @@
#!/bin/sh
# script/bootstrap: install all dependencies needed to build and develop
# this repo. Idempotent: every install is guarded by a check so already
# installed tools are skipped. Base tooling comes from nix, apt, brew,
# or apk (detected in that order); assumes nothing is present.
# goimports is installed via `go install` at a pinned commit (never
# "latest") because script/fmt runs it on the host; script/fmt-check
# does not (it runs gofmt only).
# The linter is NOT installed here: golangci-lint runs via docker only
# (script/lint), pinned by image digest, so its only prerequisite is a
# working docker.
set -eu
ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
# Pinned version, 2026-08-07 (same pin as the Dockerfile)
# goimports v0.42.0
GOIMPORTS_REF="golang.org/x/tools/cmd/goimports@009367f5c17a8d4c45a961a3a509277190a9a6f0"
PKGMGR=""
SUDO=""
APT_UPDATED=""
detect_pkgmgr() {
[ -n "$PKGMGR" ] && return 0
if command -v nix-env >/dev/null 2>&1; then
PKGMGR="nix"
elif command -v apt-get >/dev/null 2>&1; then
PKGMGR="apt"
elif command -v brew >/dev/null 2>&1; then
PKGMGR="brew"
elif command -v apk >/dev/null 2>&1; then
PKGMGR="apk"
else
echo "bootstrap: no supported package manager (nix, apt, brew, apk)" >&2
exit 1
fi
if [ "$PKGMGR" = "apt" ]; then
export DEBIAN_FRONTEND=noninteractive
if [ "$(id -u)" != "0" ]; then
SUDO="sudo"
fi
fi
}
# pkg_install <nix-attr> <apt-pkg> <brew-formula> <apk-pkg>
pkg_install() {
detect_pkgmgr
case "$PKGMGR" in
nix) nix-env -iA "nixpkgs.$1" ;;
apt)
if [ -z "$APT_UPDATED" ]; then
$SUDO env DEBIAN_FRONTEND=noninteractive apt-get update
APT_UPDATED=1
fi
$SUDO env DEBIAN_FRONTEND=noninteractive apt-get install -y "$2"
;;
brew) brew install "$3" ;;
apk) apk add --no-cache "$4" ;;
esac
}
missing() {
! command -v "$1" >/dev/null 2>&1
}
main() {
cd "$ROOT"
if missing git; then pkg_install git git git git; fi
if missing make; then pkg_install gnumake make make make; fi
if missing go; then pkg_install go golang go go; fi
# Format tools, pinned via go install (installs into
# "$(go env GOPATH)/bin"; ensure that is on your PATH).
if missing goimports; then go install "$GOIMPORTS_REF"; fi
# Linting runs via docker only (script/lint). Warn, don't fail:
# everything except `make lint` works without it.
if missing docker; then
echo "bootstrap: WARNING: docker not found; install it to" \
"run make lint and make docker." >&2
fi
go mod download
echo "bootstrap complete"
}
main "$@"
script/check
-14
View File
@@ -1,14 +0,0 @@
#!/bin/sh
# script/check: run all checks (test, lint, fmt-check). Our own
# extension to scripts-to-rule-them-all. Must not modify any files.
set -eu
SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd -P)"
main() {
"$SCRIPT_DIR/test"
"$SCRIPT_DIR/lint"
"$SCRIPT_DIR/fmt-check"
}
main "$@"
script/cibuild
-18
View File
@@ -1,18 +0,0 @@
#!/bin/sh
# script/cibuild: run the CI build. The Dockerfile's lint stage runs
# make fmt-check and golangci-lint; its builder stage runs make test
# and make build.
#
# --no-cache-filter=lint,builder runs both stages on every invocation;
# otherwise an unchanged tree is served from the layer cache and passes
# without linting or querying live DNS.
set -eu
ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
main() {
cd "$ROOT"
docker build --no-cache-filter=lint,builder .
}
main "$@"
script/docker
-18
View File
@@ -1,18 +0,0 @@
#!/bin/sh
# script/docker: build the Docker image tagged with the project name.
# The tag comes from script/projectname.
#
# --no-cache-filter=lint,builder runs the lint stage and the builder
# stage (make test) on every invocation; otherwise an unchanged tree is
# served from the layer cache without linting or querying live DNS.
set -eu
SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd -P)"
ROOT="$(cd "$SCRIPT_DIR/.." && pwd -P)"
main() {
cd "$ROOT"
docker build --no-cache-filter=lint,builder -t "$("$SCRIPT_DIR/projectname")" .
}
main "$@"
script/fmt
-13
View File
@@ -1,13 +0,0 @@
#!/bin/sh
# script/fmt: format all files (writes).
set -eu
ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
main() {
cd "$ROOT"
gofmt -s -w .
goimports -w .
}
main "$@"
script/fmt-check
-18
View File
@@ -1,18 +0,0 @@
#!/bin/sh
# script/fmt-check: check formatting (read-only). Same scope as
# script/fmt, but fails instead of writing.
set -eu
ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
main() {
cd "$ROOT"
files="$(gofmt -l .)"
if [ -n "$files" ]; then
echo "gofmt: files not formatted:" >&2
echo "$files" >&2
exit 1
fi
}
main "$@"
script/install-precommit
-16
View File
@@ -1,16 +0,0 @@
#!/bin/sh
# script/install-precommit: install the git pre-commit hook that runs
# script/precommit. Our own extension to scripts-to-rule-them-all.
set -eu
ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
main() {
cd "$ROOT"
hook=".git/hooks/pre-commit"
printf '#!/bin/sh\nset -e\nscript/precommit\n' > "$hook"
chmod +x "$hook"
echo "pre-commit hook installed: runs script/precommit"
}
main "$@"
script/lint
-28
View File
@@ -1,28 +0,0 @@
#!/bin/sh
# script/lint: run the linter. golangci-lint is never installed or run
# on the host: it runs via docker only, one way, everywhere. This
# builds Dockerfile.lint, which COPYs the repo into the digest-pinned
# golangci-lint image and lints as a build step, so a successful build
# means a clean lint.
#
# --no-cache-filter=lint forces the lint stage (source copy + linter
# run) to execute on every invocation. Without it an unchanged tree
# returns success in well under a second having linted nothing. The
# deps stage (base image + go mod download) stays cached, and no global
# cache invalidation is performed. --progress=plain keeps the linter's
# own output visible.
set -eu
ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
main() {
cd "$ROOT"
docker build \
--progress=plain \
--no-cache-filter=lint \
--target lint \
-f Dockerfile.lint \
.
}
main "$@"
script/precommit
-21
View File
@@ -1,21 +0,0 @@
#!/bin/sh
# script/precommit: run by the git pre-commit hook; fails the commit if
# checks fail. Our own extension to scripts-to-rule-them-all. Go extra:
# go mod tidy must be a no-op before the checks run.
set -eu
SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd -P)"
ROOT="$(cd "$SCRIPT_DIR/.." && pwd -P)"
main() {
cd "$ROOT"
go mod tidy
if ! git diff --exit-code -- go.mod go.sum; then
echo "precommit: go mod tidy changed go.mod/go.sum;" \
"stage the changes and retry" >&2
exit 1
fi
"$SCRIPT_DIR/check"
}
main "$@"
script/projectname
-12
View File
@@ -1,12 +0,0 @@
#!/bin/sh
# script/projectname: output the name of this project. Our own
# extension to scripts-to-rule-them-all. Other scripts that need the
# name (e.g. script/docker) call this, so they can stay identical
# across all repos.
set -eu
main() {
echo "dnswatcher"
}
main "$@"
script/setup
-13
View File
@@ -1,13 +0,0 @@
#!/bin/sh
# script/setup: set up the repo for development after a fresh clone:
# installs dependencies and the git pre-commit hook.
set -eu
SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd -P)"
main() {
"$SCRIPT_DIR/bootstrap"
"$SCRIPT_DIR/install-precommit"
}
main "$@"
script/test
-35
View File
@@ -1,35 +0,0 @@
#!/bin/sh
# script/test: run the test suite.
#
# -count=1 disables Go's test cache, and is load-bearing here. This
# suite queries live DNS on every run by policy (TESTING.md); a cached
# result is a replay of an earlier run's output with no query made at
# all. On an unchanged tree the whole suite would return success in
# under a second having resolved nothing, which makes the repeated-run
# green that is used as evidence for flakiness fixes worthless. Do not
# remove it.
#
# Conditional verbose rerun per REPO_POLICIES.md: run quiet first so
# CI and docker build logs stay readable, and rerun with -v only on
# failure. The rerun also carries -count=1 (a cached replay of the
# failure would show nothing new), and the exit status is forced to 1
# no matter how the rerun ends: the first failure already proved the
# suite broken, so a flaky test that passes the second time must not
# turn the build green.
#
# -timeout 90s is a deliberate backstop above the 60s hard cap on
# suite duration. Do not lower it.
set -eu
ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
main() {
cd "$ROOT"
go test -count=1 -race -timeout 90s -cover ./... || {
echo "--- Rerunning with -v for details ---" >&2
go test -count=1 -race -timeout 90s -v ./... || true
exit 1
}
}
main "$@"
static/css/tailwind.min.css
Vendored
-1
View File
File diff suppressed because one or more lines are too long
static/static.go
-10
View File
@@ -1,10 +0,0 @@
// Package static provides embedded static assets.
package static
import "embed"
// Static contains the embedded static assets (CSS, JS) served
// at the /s/ URL prefix.
//
//go:embed css
var Static embed.FS