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Author	SHA1	Message	Date
clawbotandsneak	e77e206fc4	next (#136 ) check / check (push) Successful in 55s Details Long-lived integration branch. One commit per work unit lands here; this PR accumulates them until it is merged to `main`. ## Landed units - Run all linting in Docker via `Dockerfile.lint` + `script/lint` — #134 golangci-lint is no longer installed or run on the host. New root `Dockerfile.lint` COPYs the repo into the digest-pinned `golangci/golangci-lint:v2.12.2` image and lints as a build step, so a successful build IS a clean lint; `script/lint` is reduced to a thin wrapper that builds it. This also works where the docker daemon is remote and bind mounts are impossible. Pinned digest and how it was verified. `golangci/golangci-lint:v2.12.2@sha256:5cceeef04e53efe1470638d4b4b4f5ceefd574955ab3941b2d9a68a8c9ad5240`, exactly as quoted in the issue. It resolves, and it is genuinely v2.12.2: ``` $ docker buildx imagetools inspect golangci/golangci-lint:v2.12.2 Name: docker.io/golangci/golangci-lint:v2.12.2 MediaType: application/vnd.oci.image.index.v1+json Digest: sha256:5cceeef04e53efe1470638d4b4b4f5ceefd574955ab3941b2d9a68a8c9ad5240 $ docker run --rm golangci/golangci-lint@sha256:5cceeef04e...ad5240 golangci-lint --version golangci-lint has version 2.12.2 built with go1.26.2 from c0d3ddc9 on 2026-05-06T11:07:58Z ``` The tag's index digest is the quoted digest, and the binary inside reports commit `c0d3ddc9`, matching the org's canonical pin `c0d3ddc9cf3faa61a4e378e879ece580256d76e5`. Forcing the linter to actually run. `Dockerfile.lint` is split into a `deps` stage (base image + `go mod download`) and a `lint` stage (source copy + linter run). `script/lint` runs: ``` docker build --progress=plain --no-cache-filter=lint --target lint -f Dockerfile.lint . ``` Caching is explicitly waived for linting, and a cached build lints nothing, so the `lint` stage is invalidated on every invocation. The invalidation is scoped: the `deps` stage stays cached and no global cache wipe is performed. `--progress=plain` keeps the linter's own output visible. `golangci-lint config verify`: deliberately NOT included. It fetches its JSON schema over a live, unpinned HTTPS call, which would make linting network-dependent and defeat hash-pinning. Omitted for that reason, and the reason is recorded in a comment at the top of `Dockerfile.lint`. `script/bootstrap` no longer installs golangci-lint (and its pinned ref is gone); it warns non-fatally when `docker` is absent instead. The `goimports` install stays, because `script/fmt` and `script/fmt-check` still run on the host. Header comment updated accordingly. Root `Dockerfile` — required consequence, not scope creep. Its builder stage ran `make check`, which now calls `script/lint`, which shells out to `docker build`; there is no docker daemon inside a docker build, so `script/cibuild` and `script/docker` would have broken. It gains its own lint stage on the same pinned image (linter invoked directly, with a comment explaining why not `make lint`), with the builder stage depending on it via `COPY --from=lint /src/go.sum /dev/null` and running `make fmt-check`, `make test`, `make build`. The now-unneeded golangci-lint install is gone from the builder stage. README `Entrypoints` and `Building` sections now describe linting as a docker-only operation. `TODO.md` updated in the same commit. ### Verification All runs via `make` / `script/` entrypoints only. Two consecutive `make lint` runs on an unchanged tree, both executing the linter: ``` # run 1 #10 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./... #10 10.98 0 issues. #10 DONE 12.0s # run 2, tree untouched #10 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./... #10 14.63 0 issues. ``` A third run shows the cache scoping is working as intended — `deps` served from cache, `lint` re-executed: ``` #6 [deps 2/4] WORKDIR /src #6 CACHED #7 [deps 3/4] COPY go.mod go.sum ./ #7 CACHED #8 [deps 4/4] RUN go mod download #8 CACHED #9 [lint 1/2] COPY . . #10 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./... ``` Negative control. A deliberate violation (an unused function containing an ineffectual assignment) was added to `internal/config/config.go`: ``` #10 11.26 internal/config/config.go:29:2: ineffectual assignment to x (ineffassign) #10 11.26 internal/config/config.go:28:6: func negativeControlUnused is unused (unused) #10 11.26 2 issues: #10 ERROR: process "/bin/sh -c golangci-lint run --config .golangci.yml ./..." did not complete successfully: exit code: 1 ERROR: failed to build: failed to solve: process "/bin/sh -c golangci-lint run --config .golangci.yml ./..." did not complete successfully: exit code: 1 make: * [Makefile:26: lint] Error 1 ``` `make lint` exited non-zero naming both findings and their exact lines. After reverting the file, `make lint` was clean again (`0 issues.`). `make check` green end to end (test, lint, fmt-check), exit 0. `script/cibuild` green, confirming the `Dockerfile` restructure does not recurse: the lint stage ran (`#16 12.56 0 issues.`), then `#22 [builder 8/9] RUN make test` with `PASS` lines, then `#23 [builder 9/9] RUN make build`. ### Notes for the owner This supersedes two PRs you still have queued for merge, both of which tune host linting that no longer exists after this change: #128 (isolates the host golangci-lint cache and lock) and #131 (always installs the pinned lint tools in `script/bootstrap`). Neither was merged or incorporated here. Made moot by this change: #121 and #130. ### Review outcome Reviewed at #136 (comment) — PASS. Three non-blocking comment-accuracy findings were recorded there for the next touch of those files; the reviewer independently confirmed the lint gate is live by negative control from a warm cache. - Live DNS tests made robust instead of gated; test caps moved to the org-wide 60s/20s/90s values — #93 The resolver's live-DNS tests failed nondeterministically, a different subset each run. Fixed by engineering the nondeterminism out, not by routing around the network. Nothing is mocked, faked, stubbed, recorded or replayed; there is no `-short` flag, no build tag, no skip, and no environment-tolerance for restricted egress. Production resolver behaviour is unchanged. ### Root causes, all test-side 1. Burst fan-out at one root server. Every test in `internal/resolver` calls `t.Parallel()` and the build hosts have many cores (48 here), so all ~35 iterative resolutions started within milliseconds of each other, and because `queryServers` walks `rootServerList()` in fixed order they all aimed their first query at `198.41.0.4`. Root servers rate-limit that, which fits the reported symptom of a different arbitrary subset failing each run. 2. No retry anywhere. One dropped UDP packet in a delegation chain failed a test outright. 3. Unanimity assertions.** `TestQueryAllNameservers_AllReturnOK` and `_NXDomainFromAllNS` required every nameserver of a domain to answer — four independent chances to fail per run, with no tolerance for one being slow. ### What was built New `internal/resolver/livedns_test.go` holds all the live-DNS machinery, so `resolver_test.go` itself takes only call-site edits: - Bounded live concurrency. A package-wide semaphore (`liveConcurrency = 6`) caps how many live resolutions are in flight at once. Tests keep `t.Parallel()`; only their network work is throttled. This is the direct fix for cause 1, and the 60s budget is what makes it affordable. - Retry with exponential backoff. Three attempts per live operation, 8s deadline each, 500ms base backoff doubling. The retry predicate is deliberately transport-level — "did a nameserver answer at all" — and never the assertion the test is making, so a resolver that answers incorrectly still fails on the first attempt rather than being retried into a false green. - Quorum instead of unanimity, tolerating SILENCE ONLY. A strict majority of the discovered nameservers must answer as expected, and every individual result must additionally fall inside a closed allowlist of statuses the test explicitly sanctions: `ok`/`timeout`/`error` for the all-OK test, `nxdomain`/`timeout`/`error` for the NXDOMAIN test. A nameserver that stays silent is tolerated; one that answers wrongly is not, at any count. The allowlist is the load-bearing part — see the rework note below for why a blocklist was not enough. New `internal/resolver/livedns_harness_test.go` tests that machinery directly — quorum arithmetic, status counting, the allowlist, the gate's concurrency bound, per-attempt deadlines, and recovery from a transient failure. It performs no DNS resolution of any kind, so it neither mocks DNS nor depends on it. ### Rework after review — the quorum could not fail on a wrong answer The review at #136 (comment) returned FAIL on `9cb2c2b`, correctly. Fixed in `87bce43`. The defect. The claim above was, as first written, false for `resolver.StatusNoData`. Each test banned exactly one wrong status — `_AllReturnOK` banned only `nxdomain`, `_NXDomainFromAllNS` banned only `ok` — and `nodata` is neither. It is a wrong answer, not silence: `answeredCount` counted it as answered, so it did not even trigger a retry, and with a quorum of 3-of-4 a single wrong nameserver slid through undetected. The pre-change unanimity assertions would have caught it. That is robustness work quietly becoming assertion-loosening, which is exactly what this repo cannot afford. The fix. Tolerance is now an allowlist, not a blocklist of one status. New `unsanctionedStatuses()` returns every per-nameserver result whose status the caller did not explicitly sanction, and each test asserts that list is empty in addition to its quorum. A blocklist bans the one wrong answer its author thought of and silently admits everything else, including any status added to the resolver later; an allowlist fails on anything nobody sanctioned. `answeredCount` was reframed the same way — it now counts the closed set `ok`/`nxdomain`/`nodata`, so an unfamiliar status is treated as silence and can only ever cause a retry and then a loud failure, never a quiet pass. Evidence — the reviewer's exact probe, re-run. `queryEachNS` in `internal/resolver/iterative.go` was patched to force one of `google.com`'s four nameservers to return `StatusNoData` with empty records. `make test` now goes red, naming the offending nameserver and status: ``` exit=2 --- FAIL: TestQueryAllNameservers_AllReturnOK (1.12s) Error: Should be empty, but was [ns1.google.com.=nodata] Messages: every nameserver must answer OK or not answer at all: ns1.google.com.=nodata ns2.google.com.=ok ns3.google.com.=ok ns4.google.com.=ok --- FAIL: TestQueryAllNameservers_NXDomainFromAllNS (1.34s) Error: Should be empty, but was [ns1.google.com.=nodata] Messages: every nameserver must report NXDOMAIN or not answer at all: ns1.google.com.=nodata ns2.google.com.=nxdomain ns3.google.com.=nxdomain ns4.google.com.=nxdomain FAIL sneak.berlin/go/dnswatcher/internal/resolver 1.704s ``` That is the same input that returned `exit=0` with both tests passing under the old assertions. Probe reverted, tree clean, suite green again: ``` exit=0 ok sneak.berlin/go/dnswatcher/internal/resolver 4.185s coverage: 77.1% of statements (zero `(cached)` lines) ``` Two harness tests lock the regression in without any probe: three OK plus one `nodata` (quorum satisfied, no NXDOMAIN present — the exact input that used to pass) is reported as unsanctioned, and an unknown status is neither counted as answered nor tolerated. Also fixed from the review: the per-attempt deadline assertion in `livedns_harness_test.go` had no lower bound, so it passed for a deadline far shorter than intended. It now asserts the remaining time exceeds `liveAttemptTimeout/2` as well. Deliberately not done in this rework, per the review and the owner: no `-count=1` in `script/test` (the test-cache issue is real but pre-existing and repo-wide, filed separately); the remaining non-DNS mocks stay for #97; `queryServers` root-ordering stays untouched under #138. ### The `-timeout` backstop value: 90s Per the ruling at sneak/prompts#41 (comment) the cap is org-wide with two tiers: 60s hard cap for CI green, 20s target, and anything between the two must be filed as an improvement bug. The backstop is `90s`, matching sneak/prompts#42 and preserving the 1.5x backstop-to-cap ratio the old 20s/30s pair had. It must strictly exceed the 60s cap or the cap is unreachable — the old `-timeout 30s` would have killed a 60s-capped suite at half its allowance. Applied to `script/test`; nothing else in the repo carried the old `30s`. Worst case for one live operation is 3 attempts x 8s plus ~1.5s of backoff, about 26s — comfortably inside the 90s backstop even if several operations exhaust their attempts at once. ### `REPO_POLICIES.md` is re-vendored, not hand-edited The file is org-canonical, so it was copied byte-for-byte from `prompts/REPO_POLICIES.md` on `sneak/prompts` branch `org-wide-60s-test-cap` (commit `52b5192`) rather than reworded to approximately the same thing. Verified: ``` $ cmp prompts/REPO_POLICIES.md dnswatcher/REPO_POLICIES.md && echo identical identical $ sha256sum REPO_POLICIES.md bcf11c312a1bee18a0e937eb412b51914411c1ab23308b8362409f3f88379ff7 ``` What that byte-identity does and does not certify. The source branch `org-wide-60s-test-cap` is an unmerged proposal — sneak/prompts#42 — not `prompts` `main`. So, precisely: - The 60s hard cap and 20s improvement-bug tier ARE the owner's ruling (sneak/prompts#41 (comment)). - The `90s` backstop is our own proposed number and is NOT ratified (sneak/prompts#41 (comment)). - The vendored text is therefore the proposed canonical text, pending sneak/prompts#42. If that PR lands with different numbers, this file must be re-vendored to match; it should not be hand-edited here either way. Known mismatch with this repo's actual state, recorded not papered over. Re-vendoring also picked up the paragraph at `REPO_POLICIES.md:266-271` mandating that canonical golangci-lint be installed commit-pinned via `go install ...@c0d3ddc9...`. This repo does not comply with that mechanism: `cc86473` in this same PR made linting Docker-only, and `script/bootstrap` now installs golangci-lint nowhere. The version and commit match (`v2.12.2` / `c0d3ddc9`); the installation mechanism does not. The vendored file is org-canonical and must not be edited downstream, so this is being raised upstream for the org text to accommodate Docker-only linting rather than patched here. `TESTING.md`'s stale "within the 30-second target" follows to 60. That edit is deliberately a single line so it merges cleanly when #97 lands. ### Verification All runs through `make` / `script/` entrypoints only; lint runs in Docker. Ten consecutive `make check` runs, all green, none served from cache. Go's test cache will happily report `ok pkg (cached)` without executing anything, which proves nothing about nondeterminism, so every run was forced to actually execute and each log was checked for zero `(cached)` lines: ``` check#1 exit=0 wall=32s resolver=2.895s fails=0 cached=0 check#2 exit=0 wall=27s resolver=2.872s fails=0 cached=0 check#3 exit=0 wall=47s resolver=2.729s fails=0 cached=0 check#4 exit=0 wall=36s resolver=2.885s fails=0 cached=0 check#5 exit=0 wall=32s resolver=2.899s fails=0 cached=0 check#6 exit=0 (harness tests added) fails=0 cached=0 check#7 exit=0 wall=41s resolver=2.891s fails=0 cached=0 check#8 exit=0 wall=36s resolver=2.871s fails=0 cached=0 check#9 exit=0 wall=26s resolver=2.846s fails=0 cached=0 check#10 exit=0 wall=46s resolver=2.833s fails=0 cached=0 ``` After the rework commit `87bce43`, `make check` green again end to end, zero `(cached)` test lines, Docker lint stage demonstrably executed rather than served from cache: ``` exit=0 cached=0 #8 [deps 4/4] RUN go mod download #8 CACHED #10 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./... #10 30.72 0 issues. ``` The Docker lint stage was confirmed to execute rather than cache on each run: ``` #8 [deps 4/4] RUN go mod download #8 CACHED #9 [lint 1/2] COPY . . #9 DONE 0.6s #10 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./... #10 DONE 39.7s ``` `make test` wall time: 3.6-4.1s across three timed uncached runs (`4093ms`, `3649ms`, `3729ms`). `internal/resolver` went from 2.0s to ~2.9s — the concurrency gate's cost. That is inside the 20s target, so no improvement bug is owed under the new two-tier rule. Honest note on what these runs do and do not prove. Live DNS was healthy throughout: no live-DNS retry fired even once, and no flake was observed either before or after the change (six pre-change baseline runs were also clean). So these runs demonstrate the change is not itself flaky and does not slow the suite; they do not demonstrate recovery from a real DNS failure, because no real DNS failure occurred. The original flakiness is not reproduced rather than shown fixed. The retry path is instead proven by `TestRetryLiveRecoversFromTransientFailure`, the only source of the single `retrying in 500ms` line in each log: ``` livedns_harness_test.go:90: transient: attempt 1 of 3 failed (no answer from live DNS), retrying in 500ms ``` ### Observation, not acted on The single most effective remaining lever against root-server rate limiting would be to stop `queryServers` always trying `rootServerList()` in the same order, so that load spreads across all thirteen roots instead of concentrating on `a.root-servers.net`. That is production code and this issue scopes the work as test-side, so it was left alone rather than changed quietly. It is now tracked for the owner's decision at #138. ### Interaction with #97 `TESTING.md` and `internal/resolver/resolver_test.go` auto-merge — that PR touches `resolver_test.go` only at the import block and the final timeout-test section, while this change touches the body of the file and adds two new files, and it leaves the mock-`DNSClient` timeout test at the tail of `resolver_test.go` entirely alone since removing it is that PR's job. `TODO.md` does conflict; that PR is already labelled `needs-rebase`, so this adds nothing material to its rebase. - Go's test cache disabled, so every `make test` actually queries live DNS — #139 `script/test` did not pass `-count=1`, so on an unchanged tree Go served the whole suite from cache: exit 0 in ~0.2s, every package marked `(cached)`, and not one DNS query made. This repo's suite exists to exercise live resolution on every run (`TESTING.md`), so that green asserted nothing — and it is exactly the green used as evidence that a flakiness fix works, since "run it a few times" stops being runs after the first. It had already misled two agents, each of whom forced uncached runs by hand. `-count=1` now disables caching on every invocation. The conditional verbose rerun was missing and is added here. `REPO_POLICIES.md` mandates it; the primary run had been unconditionally `-v`, which is the failure mode the policy exists to prevent (unreadable CI and `docker build` logs on success). Tests now run quiet, and only a failure triggers the `-v` rerun. Two properties matter and both are covered: the rerun carries `-count=1` too, so it cannot replay a cached copy of the failure it is meant to diagnose; and its exit status is discarded in favour of a forced `1`, so a flake that passes the second time cannot turn the build green — the first failure already proved the suite broken. `-timeout 90s` untouched. It is a deliberate backstop that must strictly exceed the 60s hard cap. No special-casing for the Docker build, which reaches the same script via `RUN make test`: a fresh container's test cache is empty, so `-count=1` is a no-op there, and carving out an exception would only create a second code path that could drift. ### Verification Proven from a warm cache, not a cold one. The suite was run first to populate the cache, and the pre-change state confirmed: ``` ok sneak.berlin/go/dnswatcher/internal/config (cached) coverage: 92.6% of statements ok sneak.berlin/go/dnswatcher/internal/resolver (cached) coverage: 77.1% of statements ...8 of 8 packages (cached)... real 0m0.203s ``` With the change applied to that same warm cache, three back-to-back runs on an unchanged tree, zero `(cached)` markers in all three: ``` # run 1 # run 2 ok .../internal/config 1.045s ok .../internal/config 1.040s ok .../internal/handlers 1.029s ok .../internal/handlers 1.021s ok .../internal/notify 1.148s ok .../internal/notify 1.252s ok .../internal/portcheck 1.026s ok .../internal/portcheck 1.025s ok .../internal/resolver 3.005s ok .../internal/resolver 2.846s ok .../internal/state 1.078s ok .../internal/state 1.097s ok .../internal/tlscheck 1.067s ok .../internal/tlscheck 1.079s ok .../internal/watcher 1.566s ok .../internal/watcher 1.544s real 0m4.174s real 0m4.015s # run 3: grep -c '(cached)' => 0 real 0m4.519s ``` Measured uncached wall time: 4.0-4.5s (was ~0.2s served from cache). Inside the 20s target, so no improvement bug is owed under the two-tier rule at sneak/prompts#41 (comment). `-count=1` composes with `-race` and `-cover`: both still present in the primary run, and the per-package coverage percentages above are identical to the pre-change values. The failure path was exercised, not assumed. A purpose-built flaky test that fails on its first run and passes every run after (marker file kept outside the module, so the tree stays byte-identical and a cached result would be served if caching were on) was run through the script: ``` exit code: 1 --- FAIL: TestFlaky (0.00s) FAIL flakeproof 0.013s --- Rerunning with -v for details --- --- PASS: TestFlaky (0.00s) ok flakeproof 1.014s ``` Quiet failure, verbose rerun that genuinely re-executed (it passed, so it did not replay the cached `FAIL`), and exit `1` regardless of the rerun passing. Scratch module removed afterwards. `make check` green, exit 0, with the Docker lint stage demonstrably executed rather than served from cache: ``` #8 [deps 4/4] RUN go mod download #8 CACHED #10 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./... #10 21.36 0 issues. #10 DONE 26.2s ``` `README.md` and `TESTING.md` record why the cache is waived, and `TODO.md` is updated in the same commit. ### Question for the owner, not filed as a defect The Docker lint run emits `The linter 'gomodguard' is deprecated (since v2.12.0) due to: new major version. Replaced by gomodguard_v2.` It is pre-existing and out of this issue's scope. It is not filed as an issue here because `.golangci.yml` tracks the org-canonical config, so switching to `gomodguard_v2` looks like an upstream `sneak/prompts` decision rather than a per-repo fix. Say the word and it gets filed in whichever place you consider canonical. - MIT `LICENSE` added; README states the licence — #102 The repo had no licence file at all, so publicly readable code was all-rights-reserved by default and nobody could legally use it. `LICENSE` was also the last file missing from `REPO_POLICIES.md`'s required minimum. MIT, by standing org policy rather than a per-repo call: any public repo lacking a licence gets MIT, and a private one with no licence is already all-rights-reserved. `sneak/dnswatcher` is public (`private: false` on the Gitea repo record). `README.md`'s first line now names the licence, per the Description requirement, and the License section states MIT and points at the file instead of recording the decision as pending. `TODO.md` updated in the same commit. ### Verification `LICENSE` is the canonical MIT text byte-for-byte with only the copyright line filled in (`Copyright (c) 2026 sneak`) — no clauses added, removed, reworded, or reflowed. It was not typed from memory: the file was copied from an existing verbatim MIT template on disk and only the copyright line edited (`diff` against that template shows that one line and nothing else), then the result was word-diffed against SPDX `MIT.txt` fetched from `spdx/license-list-data`, ignoring only line wrapping and the placeholder — identical. `make fmt` did not touch `LICENSE`, and cannot: `script/fmt` runs `gofmt -s -w .` and `goimports -w .` only, with no prettier or markdown step in the repo, so no exclusion was needed. `make check` green, exit 0. Tests executed rather than replayed (zero `(cached)` lines, `internal/resolver 3.098s`), and the Docker lint stage ran rather than cached: ``` #10 [deps 4/4] RUN go mod download #10 CACHED #12 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./... #12 36.44 0 issues. #12 DONE 36.7s ``` - Comment-only corrections in `script/bootstrap`, `script/cibuild`, and `Dockerfile.lint` — #137 Follow-up to this PR's own review. Nothing executable changed: the diff touches comment lines, one warning string, and `TODO.md`. - `script/bootstrap`'s header justified the pinned `goimports` install by claiming `script/fmt-check` runs it on the host. Verified against the script: `script/fmt-check` runs `gofmt -l .` and nothing else. The header now credits `script/fmt` alone. That `fmt-check` does not verify goimports at all is #119 and was deliberately left alone. - `script/cibuild`'s header still said the `Dockerfile` runs `make check`. It now describes the current file: lint stage runs `make fmt-check` and `golangci-lint`, builder stage runs `make test` and `make build`. - The `docker`-missing warning was three fragments, each re-prefixed with `bootstrap:` mid-clause. Now one sentence: `bootstrap: WARNING: docker not found; install it to run make lint and make docker.` - `Dockerfile.lint`'s comment explained why `golangci-lint config verify` is omitted but read as though the omission were free. It now states the residual risk: unknown top-level keys in `.golangci.yml` are silently ignored, so a mistyped or wrong-schema key lints clean while applying nothing. `config verify` was not added — the network-dependence reasoning stands. ### Verification `make check` green, exit 0. Tests executed rather than replayed (zero `(cached)` lines, `internal/resolver 2.820s`), Docker lint stage executed rather than cached: ``` #8 [deps 4/4] RUN go mod download #8 CACHED #10 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./... #10 13.30 0 issues. ``` Comment-only confirmed by reading the whole diff: no statement, flag, or command changed anywhere. --- ## Issues closed by this merge The commits on `next` each carry a bare `(closes #N)` in their subject, but the references in the prose above are full URLs, which Gitea's auto-close parser does not act on. Listing them here in bare form so the merge to `main` definitively closes them rather than leaving them open to be re-picked up as idle work: Closes #93 Closes #102 Closes #134 Closes #137 Closes #139 Co-authored-by: sneak <sneak@sneak.berlin> Reviewed-on: #136 Co-authored-by: clawbot <clawbot@noreply.example.org> Co-committed-by: clawbot <clawbot@noreply.example.org>	2026-09-09 14:57:55 +02:00
clawbotandsneak	9347a2838b	build: update golangci-lint to v2.12.2 with org-standard v2 config (#96 ) check / check (push) Successful in 4s Details Updates golangci-lint to v2.12.2 and sets `.golangci.yml` to the org-standard v2-schema config already deployed across the org's repos. The config change is owner-authorized (see #96 (comment) and #96 (comment)); the same file is being landed as canonical via prompts PR #24 (sneak/prompts#24). ## Changes - Commit-pinned installs: golangci-lint pinned to commit `c0d3ddc9cf3faa61a4e378e879ece580256d76e5` (v2.12.2, released 2026-05-06) in `Dockerfile` and `script/bootstrap`. - `.golangci.yml` set to the org-standard v2 config (sha256 `021cc83f4e6fc7c31b95b34b846723dfcf20b66b7baeea1dc40406e643346bcb`), byte-identical to the file used across the org's other repos. Settings live under `linters.settings`, so the `lll`/`funlen`/`cyclop`/`dupl` thresholds are actually applied (under the old hybrid file, v2 silently ignored the top-level `linters-settings` block). - Lint fixes required by the now-active thresholds: - `goconst`: shared constants for repeated status/priority/DNS-fixture strings in `internal/watcher/watcher.go` and the notify, state, and watcher tests - `dupl`: consolidated duplicated ntfy/slack HTTP-error tests and SendNotification endpoint-error tests behind shared helpers in `internal/notify/delivery_test.go` - `lll`: wrapped long test table entries and comments in `internal/config/classify_test.go`, `internal/notify/history_test.go`, `internal/state/state_test.go`, `internal/watcher/watcher_test.go`; shortened one inline nolint justification in `internal/notify/retry.go` - `TODO.md`: Completed Steps entry updated in the same commit. - Rebased onto current `main` (`f79cd98`); the branch is one clean commit. ## Notes - v2.12 deprecates the `gomodguard` linter in favor of `gomodguard_v2`. The org-standard config does not disable the deprecated linter, so golangci-lint may emit an informational deprecation warning; this is accepted by the owner and does not affect the exit status (this exact config+code combination was CI-green at `dea7e44`). ## Verification - `make check` exits 0 (fmt-check, tests, lint) - `make lint`: 0 issues; no deprecation warning surfaced in the runs performed - sha256 of `.golangci.yml` at HEAD verified equal to `021cc83f4e6fc7c31b95b34b846723dfcf20b66b7baeea1dc40406e643346bcb` Co-authored-by: sneak <sneak@sneak.berlin> Reviewed-on: #96 Co-authored-by: clawbot <clawbot@noreply.example.org> Co-committed-by: clawbot <clawbot@noreply.example.org>	2026-08-07 23:15:47 +02:00
clawbotandclawbot	23f115053b	feat: add retry with exponential backoff for notification delivery (#87 ) check / check (push) Successful in 37s Details ## Summary Notifications were fire-and-forget: if Slack, Mattermost, or ntfy was temporarily down, changes were silently lost. This adds automatic retry with exponential backoff and jitter to all notification endpoints. ## Changes ### New file: `internal/notify/retry.go` - `RetryConfig` struct with configurable max retries, base delay, max delay - `backoff()` computes delay as `BaseDelay * 2^attempt`, capped at `MaxDelay`, with ±25% jitter - `deliverWithRetry()` wraps any send function with the retry loop - Defaults: 3 retries (4 total attempts), 1s base delay, 10s max delay - Context-aware: respects cancellation during retry sleep - Injectable `sleepFn` for test determinism ### Modified: `internal/notify/notify.go` - Added `retryConfig` and `sleepFn` fields to `Service` - Updated `dispatchNtfy`, `dispatchSlack`, `dispatchMattermost` to wrap sends in `deliverWithRetry` - Structured logging: warns on each retry, logs error only after all retries exhausted, logs info on success after retry ### Modified: `internal/notify/export_test.go` - Added test helpers: `SetRetryConfig`, `SetSleepFunc`, `DeliverWithRetry`, `BackoffDuration` ### New file: `internal/notify/retry_test.go` - Backoff calculation tests (exponential increase, max cap with jitter) - `deliverWithRetry` unit tests: first-attempt success, transient failure recovery, exhausted retries, context cancellation - Integration tests via `SendNotification`: transient failure retries, all-endpoints retry independently, permanent failure exhausts retries ## Verification - `make fmt` ✅ - `make check` (format + lint + tests + build) ✅ - `docker build .` ✅ - All existing tests continue to pass unchanged - No DNS client mocking — notification tests use `httptest` servers closes #62 Co-authored-by: clawbot <clawbot@noreply.git.eeqj.de> Reviewed-on: #87 Co-authored-by: clawbot <clawbot@noreply.example.org> Co-committed-by: clawbot <clawbot@noreply.example.org>	2026-03-22 07:14:59 +01:00

Author

SHA1

Message

Date

clawbotandsneak

e77e206fc4

next (#136 )

check / check (push) Successful in 55s

Details

Long-lived integration branch. One commit per work unit lands here; this PR accumulates them until it is merged to `main`.

## Landed units

- **Run all linting in Docker via `Dockerfile.lint` + `script/lint`** — #134

golangci-lint is no longer installed or run on the host. New root `Dockerfile.lint` COPYs the repo into the digest-pinned `golangci/golangci-lint:v2.12.2` image and lints as a build step, so a successful build IS a clean lint; `script/lint` is reduced to a thin wrapper that builds it. This also works where the docker daemon is remote and bind mounts are impossible.

**Pinned digest and how it was verified.** `golangci/golangci-lint:v2.12.2@sha256:5cceeef04e53efe1470638d4b4b4f5ceefd574955ab3941b2d9a68a8c9ad5240`, exactly as quoted in the issue. It resolves, and it is genuinely v2.12.2:

```
$ docker buildx imagetools inspect golangci/golangci-lint:v2.12.2
Name: docker.io/golangci/golangci-lint:v2.12.2
MediaType: application/vnd.oci.image.index.v1+json
Digest: sha256:5cceeef04e53efe1470638d4b4b4f5ceefd574955ab3941b2d9a68a8c9ad5240

$ docker run --rm golangci/golangci-lint@sha256:5cceeef04e...ad5240 golangci-lint --version
golangci-lint has version 2.12.2 built with go1.26.2 from c0d3ddc9 on 2026-05-06T11:07:58Z
```

The tag's index digest is the quoted digest, and the binary inside reports commit `c0d3ddc9`, matching the org's canonical pin `c0d3ddc9cf3faa61a4e378e879ece580256d76e5`.

**Forcing the linter to actually run.** `Dockerfile.lint` is split into a `deps` stage (base image + `go mod download`) and a `lint` stage (source copy + linter run). `script/lint` runs:

```
docker build --progress=plain --no-cache-filter=lint --target lint -f Dockerfile.lint .
```

Caching is explicitly waived for linting, and a cached build lints nothing, so the `lint` stage is invalidated on every invocation. The invalidation is scoped: the `deps` stage stays cached and no global cache wipe is performed. `--progress=plain` keeps the linter's own output visible.

**`golangci-lint config verify`: deliberately NOT included.** It fetches its JSON schema over a live, unpinned HTTPS call, which would make linting network-dependent and defeat hash-pinning. Omitted for that reason, and the reason is recorded in a comment at the top of `Dockerfile.lint`.

**`script/bootstrap`** no longer installs golangci-lint (and its pinned ref is gone); it warns non-fatally when `docker` is absent instead. The `goimports` install stays, because `script/fmt` and `script/fmt-check` still run on the host. Header comment updated accordingly.

**Root `Dockerfile`** — required consequence, not scope creep. Its builder stage ran `make check`, which now calls `script/lint`, which shells out to `docker build`; there is no docker daemon inside a docker build, so `script/cibuild` and `script/docker` would have broken. It gains its own lint stage on the same pinned image (linter invoked directly, with a comment explaining why not `make lint`), with the builder stage depending on it via `COPY --from=lint /src/go.sum /dev/null` and running `make fmt-check`, `make test`, `make build`. The now-unneeded golangci-lint install is gone from the builder stage.

**README** `Entrypoints` and `Building` sections now describe linting as a docker-only operation. `TODO.md` updated in the same commit.

### Verification

All runs via `make` / `script/` entrypoints only.

Two consecutive `make lint` runs on an unchanged tree, both executing the linter:

```
# run 1
#10 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./...
#10 10.98 0 issues.
#10 DONE 12.0s

# run 2, tree untouched
#10 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./...
#10 14.63 0 issues.
```

A third run shows the cache scoping is working as intended — `deps` served from cache, `lint` re-executed:

```
#6 [deps 2/4] WORKDIR /src
#6 CACHED
#7 [deps 3/4] COPY go.mod go.sum ./
#7 CACHED
#8 [deps 4/4] RUN go mod download
#8 CACHED
#9 [lint 1/2] COPY . .
#10 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./...
```

**Negative control.** A deliberate violation (an unused function containing an ineffectual assignment) was added to `internal/config/config.go`:

```
#10 11.26 internal/config/config.go:29:2: ineffectual assignment to x (ineffassign)
#10 11.26 internal/config/config.go:28:6: func negativeControlUnused is unused (unused)
#10 11.26 2 issues:
#10 ERROR: process "/bin/sh -c golangci-lint run --config .golangci.yml ./..." did not complete successfully: exit code: 1
ERROR: failed to build: failed to solve: process "/bin/sh -c golangci-lint run --config .golangci.yml ./..." did not complete successfully: exit code: 1
make: *** [Makefile:26: lint] Error 1
```

`make lint` exited non-zero naming both findings and their exact lines. After reverting the file, `make lint` was clean again (`0 issues.`).

**`make check`** green end to end (test, lint, fmt-check), exit 0.

**`script/cibuild`** green, confirming the `Dockerfile` restructure does not recurse: the lint stage ran (`#16 12.56 0 issues.`), then `#22 [builder 8/9] RUN make test` with `PASS` lines, then `#23 [builder 9/9] RUN make build`.

### Notes for the owner

This supersedes two PRs you still have queued for merge, both of which tune host linting that no longer exists after this change: #128 (isolates the host golangci-lint cache and lock) and #131 (always installs the pinned lint tools in `script/bootstrap`). Neither was merged or incorporated here.

Made moot by this change: #121 and #130.

### Review outcome

Reviewed at #136 (comment) — **PASS**. Three non-blocking comment-accuracy findings were recorded there for the next touch of those files; the reviewer independently confirmed the lint gate is live by negative control from a warm cache.

- **Live DNS tests made robust instead of gated; test caps moved to the org-wide 60s/20s/90s values** — #93

The resolver's live-DNS tests failed nondeterministically, a different subset each run. Fixed by engineering the nondeterminism out, not by routing around the network. **Nothing is mocked, faked, stubbed, recorded or replayed; there is no `-short` flag, no build tag, no skip, and no environment-tolerance for restricted egress.** Production resolver behaviour is unchanged.

### Root causes, all test-side

1. **Burst fan-out at one root server.** Every test in `internal/resolver` calls `t.Parallel()` and the build hosts have many cores (48 here), so all ~35 iterative resolutions started within milliseconds of each other, and because `queryServers` walks `rootServerList()` in fixed order they all aimed their first query at `198.41.0.4`. Root servers rate-limit that, which fits the reported symptom of a different arbitrary subset failing each run.
2. **No retry anywhere.** One dropped UDP packet in a delegation chain failed a test outright.
3. **Unanimity assertions.** `TestQueryAllNameservers_AllReturnOK` and `_NXDomainFromAllNS` required *every* nameserver of a domain to answer — four independent chances to fail per run, with no tolerance for one being slow.

### What was built

New `internal/resolver/livedns_test.go` holds all the live-DNS machinery, so `resolver_test.go` itself takes only call-site edits:

- **Bounded live concurrency.** A package-wide semaphore (`liveConcurrency = 6`) caps how many live resolutions are in flight at once. Tests keep `t.Parallel()`; only their network work is throttled. This is the direct fix for cause 1, and the 60s budget is what makes it affordable.
- **Retry with exponential backoff.** Three attempts per live operation, 8s deadline each, 500ms base backoff doubling. The retry predicate is deliberately **transport-level** — "did a nameserver answer at all" — and never the assertion the test is making, so a resolver that answers *incorrectly* still fails on the first attempt rather than being retried into a false green.
- **Quorum instead of unanimity, tolerating SILENCE ONLY.** A strict majority of the discovered nameservers must answer as expected, and every individual result must additionally fall inside a closed **allowlist** of statuses the test explicitly sanctions: `ok`/`timeout`/`error` for the all-OK test, `nxdomain`/`timeout`/`error` for the NXDOMAIN test. A nameserver that stays silent is tolerated; one that answers **wrongly** is not, at any count. The allowlist is the load-bearing part — see the rework note below for why a blocklist was not enough.

New `internal/resolver/livedns_harness_test.go` tests that machinery directly — quorum arithmetic, status counting, the allowlist, the gate's concurrency bound, per-attempt deadlines, and recovery from a transient failure. It performs no DNS resolution of any kind, so it neither mocks DNS nor depends on it.

### Rework after review — the quorum could not fail on a wrong answer

The review at #136 (comment) returned **FAIL** on `9cb2c2b`, correctly. Fixed in `87bce43`.

**The defect.** The claim above was, as first written, false for `resolver.StatusNoData`. Each test banned exactly one wrong status — `_AllReturnOK` banned only `nxdomain`, `_NXDomainFromAllNS` banned only `ok` — and `nodata` is neither. It is a **wrong answer, not silence**: `answeredCount` counted it as answered, so it did not even trigger a retry, and with a quorum of 3-of-4 a single wrong nameserver slid through undetected. The pre-change unanimity assertions would have caught it. That is robustness work quietly becoming assertion-loosening, which is exactly what this repo cannot afford.

**The fix.** Tolerance is now an allowlist, not a blocklist of one status. New `unsanctionedStatuses()` returns every per-nameserver result whose status the caller did not explicitly sanction, and each test asserts that list is empty in addition to its quorum. A blocklist bans the one wrong answer its author thought of and silently admits everything else, including any status added to the resolver later; an allowlist fails on anything nobody sanctioned. `answeredCount` was reframed the same way — it now counts the closed set `ok`/`nxdomain`/`nodata`, so an unfamiliar status is treated as silence and can only ever cause a retry and then a loud failure, never a quiet pass.

**Evidence — the reviewer's exact probe, re-run.** `queryEachNS` in `internal/resolver/iterative.go` was patched to force one of `google.com`'s four nameservers to return `StatusNoData` with empty records. `make test` now goes **red**, naming the offending nameserver and status:

```
exit=2
--- FAIL: TestQueryAllNameservers_AllReturnOK (1.12s)
Error: Should be empty, but was [ns1.google.com.=nodata]
Messages: every nameserver must answer OK or not answer at all:
ns1.google.com.=nodata ns2.google.com.=ok
ns3.google.com.=ok ns4.google.com.=ok
--- FAIL: TestQueryAllNameservers_NXDomainFromAllNS (1.34s)
Error: Should be empty, but was [ns1.google.com.=nodata]
Messages: every nameserver must report NXDOMAIN or not answer at all:
ns1.google.com.=nodata ns2.google.com.=nxdomain
ns3.google.com.=nxdomain ns4.google.com.=nxdomain
FAIL sneak.berlin/go/dnswatcher/internal/resolver 1.704s
```

That is the same input that returned `exit=0` with both tests **passing** under the old assertions. Probe reverted, tree clean, suite green again:

```
exit=0
ok sneak.berlin/go/dnswatcher/internal/resolver 4.185s coverage: 77.1% of statements
(zero `(cached)` lines)
```

Two harness tests lock the regression in without any probe: three OK plus one `nodata` (quorum satisfied, no NXDOMAIN present — the exact input that used to pass) is reported as unsanctioned, and an unknown status is neither counted as answered nor tolerated.

Also fixed from the review: the per-attempt deadline assertion in `livedns_harness_test.go` had no lower bound, so it passed for a deadline far shorter than intended. It now asserts the remaining time exceeds `liveAttemptTimeout/2` as well.

Deliberately **not** done in this rework, per the review and the owner: no `-count=1` in `script/test` (the test-cache issue is real but pre-existing and repo-wide, filed separately); the remaining non-DNS mocks stay for #97; `queryServers` root-ordering stays untouched under #138.

### The `-timeout` backstop value: 90s

Per the ruling at sneak/prompts#41 (comment) the cap is org-wide with two tiers: **60s hard cap for CI green, 20s target, and anything between the two must be filed as an improvement bug.** The backstop is **`90s`**, matching sneak/prompts#42 and preserving the 1.5x backstop-to-cap ratio the old 20s/30s pair had. It must strictly exceed the 60s cap or the cap is unreachable — the old `-timeout 30s` would have killed a 60s-capped suite at half its allowance. Applied to `script/test`; nothing else in the repo carried the old `30s`.

Worst case for one live operation is 3 attempts x 8s plus ~1.5s of backoff, about 26s — comfortably inside the 90s backstop even if several operations exhaust their attempts at once.

### `REPO_POLICIES.md` is re-vendored, not hand-edited

The file is org-canonical, so it was **copied byte-for-byte** from `prompts/REPO_POLICIES.md` on `sneak/prompts` branch `org-wide-60s-test-cap` (commit `52b5192`) rather than reworded to approximately the same thing. Verified:

```
$ cmp prompts/REPO_POLICIES.md dnswatcher/REPO_POLICIES.md && echo identical
identical
$ sha256sum REPO_POLICIES.md
bcf11c312a1bee18a0e937eb412b51914411c1ab23308b8362409f3f88379ff7
```

**What that byte-identity does and does not certify.** The source branch `org-wide-60s-test-cap` is an **unmerged proposal** — sneak/prompts#42 — not `prompts` `main`. So, precisely:

- The **60s hard cap and 20s improvement-bug tier ARE the owner's ruling** (sneak/prompts#41 (comment)).
- The **`90s` backstop is our own proposed number and is NOT ratified** (sneak/prompts#41 (comment)).
- The vendored text is therefore **the proposed canonical text, pending** sneak/prompts#42. If that PR lands with different numbers, this file must be re-vendored to match; it should not be hand-edited here either way.

**Known mismatch with this repo's actual state, recorded not papered over.** Re-vendoring also picked up the paragraph at `REPO_POLICIES.md:266-271` mandating that canonical golangci-lint be installed commit-pinned via `go install ...@c0d3ddc9...`. This repo does **not** comply with that mechanism: `cc86473` in this same PR made linting Docker-only, and `script/bootstrap` now installs golangci-lint nowhere. The **version and commit match** (`v2.12.2` / `c0d3ddc9`); the **installation mechanism does not**. The vendored file is org-canonical and must not be edited downstream, so this is being raised upstream for the org text to accommodate Docker-only linting rather than patched here.

`TESTING.md`'s stale "within the 30-second target" follows to 60. That edit is deliberately a single line so it merges cleanly when #97 lands.

### Verification

All runs through `make` / `script/` entrypoints only; lint runs in Docker.

**Ten consecutive `make check` runs, all green, none served from cache.** Go's test cache will happily report `ok pkg (cached)` without executing anything, which proves nothing about nondeterminism, so every run was forced to actually execute and each log was checked for zero `(cached)` lines:

```
check#1 exit=0 wall=32s resolver=2.895s fails=0 cached=0
check#2 exit=0 wall=27s resolver=2.872s fails=0 cached=0
check#3 exit=0 wall=47s resolver=2.729s fails=0 cached=0
check#4 exit=0 wall=36s resolver=2.885s fails=0 cached=0
check#5 exit=0 wall=32s resolver=2.899s fails=0 cached=0
check#6 exit=0 (harness tests added) fails=0 cached=0
check#7 exit=0 wall=41s resolver=2.891s fails=0 cached=0
check#8 exit=0 wall=36s resolver=2.871s fails=0 cached=0
check#9 exit=0 wall=26s resolver=2.846s fails=0 cached=0
check#10 exit=0 wall=46s resolver=2.833s fails=0 cached=0
```

After the rework commit `87bce43`, `make check` green again end to end, zero `(cached)` test lines, Docker lint stage demonstrably executed rather than served from cache:

```
exit=0 cached=0
#8 [deps 4/4] RUN go mod download
#8 CACHED
#10 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./...
#10 30.72 0 issues.
```

The Docker lint stage was confirmed to execute rather than cache on each run:

```
#8 [deps 4/4] RUN go mod download
#8 CACHED
#9 [lint 1/2] COPY . .
#9 DONE 0.6s
#10 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./...
#10 DONE 39.7s
```

**`make test` wall time: 3.6-4.1s** across three timed uncached runs (`4093ms`, `3649ms`, `3729ms`). `internal/resolver` went from 2.0s to ~2.9s — the concurrency gate's cost. That is inside the 20s target, so no improvement bug is owed under the new two-tier rule.

**Honest note on what these runs do and do not prove.** Live DNS was healthy throughout: **no live-DNS retry fired even once**, and no flake was observed either before or after the change (six pre-change baseline runs were also clean). So these runs demonstrate the change is not itself flaky and does not slow the suite; they do **not** demonstrate recovery from a real DNS failure, because no real DNS failure occurred. The original flakiness is *not reproduced* rather than *shown fixed*. The retry path is instead proven by `TestRetryLiveRecoversFromTransientFailure`, the only source of the single `retrying in 500ms` line in each log:

```
livedns_harness_test.go:90: transient: attempt 1 of 3 failed
(no answer from live DNS), retrying in 500ms
```

### Observation, not acted on

The single most effective remaining lever against root-server rate limiting would be to stop `queryServers` always trying `rootServerList()` in the same order, so that load spreads across all thirteen roots instead of concentrating on `a.root-servers.net`. That is **production** code and this issue scopes the work as test-side, so it was left alone rather than changed quietly. It is now tracked for the owner's decision at #138.

### Interaction with #97

`TESTING.md` and `internal/resolver/resolver_test.go` auto-merge — that PR touches `resolver_test.go` only at the import block and the final timeout-test section, while this change touches the body of the file and adds two new files, and it leaves the mock-`DNSClient` timeout test at the tail of `resolver_test.go` entirely alone since removing it is that PR's job. `TODO.md` does conflict; that PR is already labelled `needs-rebase`, so this adds nothing material to its rebase.

- **Go's test cache disabled, so every `make test` actually queries live DNS** — #139

`script/test` did not pass `-count=1`, so on an unchanged tree Go served the whole suite from cache: exit 0 in ~0.2s, every package marked `(cached)`, and not one DNS query made. This repo's suite exists to exercise live resolution on every run (`TESTING.md`), so that green asserted nothing — and it is exactly the green used as evidence that a flakiness fix works, since "run it a few times" stops being runs after the first. It had already misled two agents, each of whom forced uncached runs by hand.

`-count=1` now disables caching on every invocation.

**The conditional verbose rerun was missing and is added here.** `REPO_POLICIES.md` mandates it; the primary run had been unconditionally `-v`, which is the failure mode the policy exists to prevent (unreadable CI and `docker build` logs on success). Tests now run quiet, and only a failure triggers the `-v` rerun. Two properties matter and both are covered: the rerun carries `-count=1` too, so it cannot replay a cached copy of the failure it is meant to diagnose; and its exit status is discarded in favour of a forced `1`, so a flake that passes the second time cannot turn the build green — the first failure already proved the suite broken.

**`-timeout 90s` untouched.** It is a deliberate backstop that must strictly exceed the 60s hard cap.

**No special-casing for the Docker build**, which reaches the same script via `RUN make test`: a fresh container's test cache is empty, so `-count=1` is a no-op there, and carving out an exception would only create a second code path that could drift.

### Verification

**Proven from a warm cache, not a cold one.** The suite was run first to populate the cache, and the pre-change state confirmed:

```
ok sneak.berlin/go/dnswatcher/internal/config (cached) coverage: 92.6% of statements
ok sneak.berlin/go/dnswatcher/internal/resolver (cached) coverage: 77.1% of statements
...8 of 8 packages (cached)...
real 0m0.203s
```

With the change applied to that same warm cache, three back-to-back runs on an unchanged tree, **zero `(cached)` markers** in all three:

```
# run 1 # run 2
ok .../internal/config 1.045s ok .../internal/config 1.040s
ok .../internal/handlers 1.029s ok .../internal/handlers 1.021s
ok .../internal/notify 1.148s ok .../internal/notify 1.252s
ok .../internal/portcheck 1.026s ok .../internal/portcheck 1.025s
ok .../internal/resolver 3.005s ok .../internal/resolver 2.846s
ok .../internal/state 1.078s ok .../internal/state 1.097s
ok .../internal/tlscheck 1.067s ok .../internal/tlscheck 1.079s
ok .../internal/watcher 1.566s ok .../internal/watcher 1.544s
real 0m4.174s real 0m4.015s

# run 3: grep -c '(cached)' => 0 real 0m4.519s
```

**Measured uncached wall time: 4.0-4.5s** (was ~0.2s served from cache). Inside the 20s target, so no improvement bug is owed under the two-tier rule at sneak/prompts#41 (comment).

**`-count=1` composes with `-race` and `-cover`**: both still present in the primary run, and the per-package coverage percentages above are identical to the pre-change values.

**The failure path was exercised, not assumed.** A purpose-built flaky test that fails on its first run and passes every run after (marker file kept outside the module, so the tree stays byte-identical and a cached result would be served if caching were on) was run through the script:

```
exit code: 1
--- FAIL: TestFlaky (0.00s)
FAIL flakeproof 0.013s
--- Rerunning with -v for details ---
--- PASS: TestFlaky (0.00s)
ok flakeproof 1.014s
```

Quiet failure, verbose rerun that genuinely re-executed (it passed, so it did not replay the cached `FAIL`), and exit `1` regardless of the rerun passing. Scratch module removed afterwards.

**`make check` green**, exit 0, with the Docker lint stage demonstrably executed rather than served from cache:

```
#8 [deps 4/4] RUN go mod download
#8 CACHED
#10 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./...
#10 21.36 0 issues.
#10 DONE 26.2s
```

`README.md` and `TESTING.md` record why the cache is waived, and `TODO.md` is updated in the same commit.

### Question for the owner, not filed as a defect

The Docker lint run emits `The linter 'gomodguard' is deprecated (since v2.12.0) due to: new major version. Replaced by gomodguard_v2.` It is pre-existing and out of this issue's scope. It is not filed as an issue here because `.golangci.yml` tracks the org-canonical config, so switching to `gomodguard_v2` looks like an upstream `sneak/prompts` decision rather than a per-repo fix. Say the word and it gets filed in whichever place you consider canonical.

- **MIT `LICENSE` added; README states the licence** — #102

The repo had no licence file at all, so publicly readable code was all-rights-reserved by default and nobody could legally use it. `LICENSE` was also the last file missing from `REPO_POLICIES.md`'s required minimum.

MIT, by standing org policy rather than a per-repo call: any public repo lacking a licence gets MIT, and a private one with no licence is already all-rights-reserved. `sneak/dnswatcher` is public (`private: false` on the Gitea repo record).

`README.md`'s first line now names the licence, per the Description requirement, and the License section states MIT and points at the file instead of recording the decision as pending. `TODO.md` updated in the same commit.

### Verification

`LICENSE` is the canonical MIT text byte-for-byte with only the copyright line filled in (`Copyright (c) 2026 sneak`) — no clauses added, removed, reworded, or reflowed. It was not typed from memory: the file was copied from an existing verbatim MIT template on disk and only the copyright line edited (`diff` against that template shows that one line and nothing else), then the result was word-diffed against SPDX `MIT.txt` fetched from `spdx/license-list-data`, ignoring only line wrapping and the placeholder — identical.

`make fmt` did **not** touch `LICENSE`, and cannot: `script/fmt` runs `gofmt -s -w .` and `goimports -w .` only, with no prettier or markdown step in the repo, so no exclusion was needed.

`make check` green, exit 0. Tests executed rather than replayed (zero `(cached)` lines, `internal/resolver 3.098s`), and the Docker lint stage ran rather than cached:

```
#10 [deps 4/4] RUN go mod download
#10 CACHED
#12 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./...
#12 36.44 0 issues.
#12 DONE 36.7s
```

- **Comment-only corrections in `script/bootstrap`, `script/cibuild`, and `Dockerfile.lint`** — #137

Follow-up to this PR's own review. Nothing executable changed: the diff touches comment lines, one warning string, and `TODO.md`.

- `script/bootstrap`'s header justified the pinned `goimports` install by claiming `script/fmt-check` runs it on the host. Verified against the script: `script/fmt-check` runs `gofmt -l .` and nothing else. The header now credits `script/fmt` alone. That `fmt-check` does not verify goimports at all is #119 and was deliberately left alone.
- `script/cibuild`'s header still said the `Dockerfile` runs `make check`. It now describes the current file: lint stage runs `make fmt-check` and `golangci-lint`, builder stage runs `make test` and `make build`.
- The `docker`-missing warning was three fragments, each re-prefixed with `bootstrap:` mid-clause. Now one sentence: `bootstrap: WARNING: docker not found; install it to run make lint and make docker.`
- `Dockerfile.lint`'s comment explained why `golangci-lint config verify` is omitted but read as though the omission were free. It now states the residual risk: unknown top-level keys in `.golangci.yml` are silently ignored, so a mistyped or wrong-schema key lints clean while applying nothing. `config verify` was **not** added — the network-dependence reasoning stands.

### Verification

`make check` green, exit 0. Tests executed rather than replayed (zero `(cached)` lines, `internal/resolver 2.820s`), Docker lint stage executed rather than cached:

```
#8 [deps 4/4] RUN go mod download
#8 CACHED
#10 [lint 2/2] RUN golangci-lint run --config .golangci.yml ./...
#10 13.30 0 issues.
```

Comment-only confirmed by reading the whole diff: no statement, flag, or command changed anywhere.

---

## Issues closed by this merge

The commits on `next` each carry a bare `(closes #N)` in their subject, but the
references in the prose above are full URLs, which Gitea's auto-close parser
does not act on. Listing them here in bare form so the merge to `main`
definitively closes them rather than leaving them open to be re-picked up as
idle work:

Closes #93
Closes #102
Closes #134
Closes #137
Closes #139

Co-authored-by: sneak <sneak@sneak.berlin>
Reviewed-on: #136
Co-authored-by: clawbot <clawbot@noreply.example.org>
Co-committed-by: clawbot <clawbot@noreply.example.org>

2026-09-09 14:57:55 +02:00

clawbotandsneak

9347a2838b

build: update golangci-lint to v2.12.2 with org-standard v2 config (#96 )

check / check (push) Successful in 4s

Details

Updates golangci-lint to v2.12.2 and sets `.golangci.yml` to the org-standard v2-schema config already deployed across the org's repos. The config change is owner-authorized (see #96 (comment) and #96 (comment)); the same file is being landed as canonical via prompts PR #24 (sneak/prompts#24).

## Changes

- **Commit-pinned installs**: golangci-lint pinned to commit `c0d3ddc9cf3faa61a4e378e879ece580256d76e5` (v2.12.2, released 2026-05-06) in `Dockerfile` and `script/bootstrap`.
- **`.golangci.yml` set to the org-standard v2 config** (sha256 `021cc83f4e6fc7c31b95b34b846723dfcf20b66b7baeea1dc40406e643346bcb`), byte-identical to the file used across the org's other repos. Settings live under `linters.settings`, so the `lll`/`funlen`/`cyclop`/`dupl` thresholds are actually applied (under the old hybrid file, v2 silently ignored the top-level `linters-settings` block).
- **Lint fixes** required by the now-active thresholds:
  - `goconst`: shared constants for repeated status/priority/DNS-fixture strings in `internal/watcher/watcher.go` and the notify, state, and watcher tests
  - `dupl`: consolidated duplicated ntfy/slack HTTP-error tests and SendNotification endpoint-error tests behind shared helpers in `internal/notify/delivery_test.go`
  - `lll`: wrapped long test table entries and comments in `internal/config/classify_test.go`, `internal/notify/history_test.go`, `internal/state/state_test.go`, `internal/watcher/watcher_test.go`; shortened one inline nolint justification in `internal/notify/retry.go`
- **`TODO.md`**: Completed Steps entry updated in the same commit.
- Rebased onto current `main` (`f79cd98`); the branch is one clean commit.

## Notes

- v2.12 deprecates the `gomodguard` linter in favor of `gomodguard_v2`. The org-standard config does not disable the deprecated linter, so golangci-lint may emit an informational deprecation warning; this is accepted by the owner and does not affect the exit status (this exact config+code combination was CI-green at `dea7e44`).

## Verification

- `make check` exits 0 (fmt-check, tests, lint)
- `make lint`: 0 issues; no deprecation warning surfaced in the runs performed
- sha256 of `.golangci.yml` at HEAD verified equal to `021cc83f4e6fc7c31b95b34b846723dfcf20b66b7baeea1dc40406e643346bcb`

Co-authored-by: sneak <sneak@sneak.berlin>
Reviewed-on: #96
Co-authored-by: clawbot <clawbot@noreply.example.org>
Co-committed-by: clawbot <clawbot@noreply.example.org>

2026-08-07 23:15:47 +02:00

clawbotandclawbot

23f115053b

feat: add retry with exponential backoff for notification delivery (#87 )

check / check (push) Successful in 37s

Details

## Summary

Notifications were fire-and-forget: if Slack, Mattermost, or ntfy was temporarily down, changes were silently lost. This adds automatic retry with exponential backoff and jitter to all notification endpoints.

## Changes

### New file: `internal/notify/retry.go`
- `RetryConfig` struct with configurable max retries, base delay, max delay
- `backoff()` computes delay as `BaseDelay * 2^attempt`, capped at `MaxDelay`, with ±25% jitter
- `deliverWithRetry()` wraps any send function with the retry loop
- Defaults: 3 retries (4 total attempts), 1s base delay, 10s max delay
- Context-aware: respects cancellation during retry sleep
- Injectable `sleepFn` for test determinism

### Modified: `internal/notify/notify.go`
- Added `retryConfig` and `sleepFn` fields to `Service`
- Updated `dispatchNtfy`, `dispatchSlack`, `dispatchMattermost` to wrap sends in `deliverWithRetry`
- Structured logging: warns on each retry, logs error only after all retries exhausted, logs info on success after retry

### Modified: `internal/notify/export_test.go`
- Added test helpers: `SetRetryConfig`, `SetSleepFunc`, `DeliverWithRetry`, `BackoffDuration`

### New file: `internal/notify/retry_test.go`
- Backoff calculation tests (exponential increase, max cap with jitter)
- `deliverWithRetry` unit tests: first-attempt success, transient failure recovery, exhausted retries, context cancellation
- Integration tests via `SendNotification`: transient failure retries, all-endpoints retry independently, permanent failure exhausts retries

## Verification
- `make fmt` ✅
- `make check` (format + lint + tests + build) ✅
- `docker build .` ✅
- All existing tests continue to pass unchanged
- No DNS client mocking — notification tests use `httptest` servers

closes #62

Co-authored-by: clawbot <clawbot@noreply.git.eeqj.de>
Reviewed-on: #87
Co-authored-by: clawbot <clawbot@noreply.example.org>
Co-committed-by: clawbot <clawbot@noreply.example.org>

2026-03-22 07:14:59 +01:00