Files
vaultik/Dockerfile
sneak d257f8f658
All checks were successful
check / check (pull_request) Successful in 2m58s
Lint in a container as a build step, via Dockerfile.lint (closes #113)
Every lint run now happens inside its own container, invoked through
script/lint, and linting is a build step rather than a container
command: a successful build of the new root Dockerfile.lint IS a clean
lint. That shape also works where the docker daemon is remote and bind
mounts are impossible.

Its FROM line -- golangci/golangci-lint:v2.12.2, pinned by digest -- is
now the only pin of the linter version in this repo.

A container per run has its own lint cache and its own golangci-lint
lock, both discarded with it, so neither cross-worktree contamination
nor lock contention exists any more. The machinery that defended
against them is therefore gone: the per-worktree cache directories, the
lock-retry loop, and script/lint-audit, which existed to catch findings
replayed from a cache that no longer exists. So is the host lint path
in its entirety -- the native escape hatch, its version detection, and
VAULTIK_LINT_IN_CONTAINER in both script/lint and the Dockerfile.
Nothing lints on the host, at any version.

A cached build lints nothing, so the CHECK_EPOCH mechanism the product
Dockerfile already used is what makes a green mean something:
ARG CHECK_EPOCH with no default, placed below the module layers so
dependency caching survives, a `RUN [ -n "$CHECK_EPOCH" ] || exit 1`
guard so a build that withholds the arg fails instead of replaying, and
the value expanded into the lint command itself. script/lint computes
`epoch="$(date +%s%N)$$"` as a bare assignment on its own line, because
inline in the argument a failing substitution does not abort under
`set -eu` and yields a constant empty epoch -- which is exactly the
false green being prevented.

The product Dockerfile loses its lint stage rather than gaining a
second linter pin. That stage ran `make lint`, which is now
`docker build`: docker-in-docker inside a BuildKit step with no daemon.
Calling golangci-lint directly there instead would have meant two
independently bumpable digests for one tool. `make fmt-check` moves
beside `make test` in the builder stage, and script/cibuild now builds
Dockerfile.lint and then Dockerfile, each with its own fresh epoch,
failing on either. Consequence, stated in comments rather than left to
be discovered: script/docker builds the product image only and no
longer lints; script/check and script/cibuild are the gates.

`golangci-lint config verify` runs as its own epoch-keyed layer, above
the lint. It is not belt-and-braces: `golangci-lint run` rejects a
config it cannot PARSE but silently IGNORES an unknown top-level KEY.
Renaming .golangci.yml's `linters:` to `linterz:` -- one character --
discards `default: all`, the disable list and every threshold, leaves
only the small default linter set running, and exits 0 reporting
`0 issues.` on a tree the real config fails with an lll finding, in a
run whose lint layer demonstrably executed. That is a set-but-
ineffective config falling back to defaults instead of failing loudly,
sitting in the gate's own configuration. `config verify` catches it and
does so with the network genuinely off at this pin: under
`docker run --network none` against the pinned digest it exits 0 on
this repo's config and exits 3 on the `linterz:` variant. It is keyed
on CHECK_EPOCH like the lint itself, because a cached validation
validates nothing.

script/lint-fix is kept, reimplemented as a bind-mounted
docker run against the image parsed out of Dockerfile.lint -- a build
step cannot write fixes back to the worktree -- and its header states
outright that it is a developer convenience, never a gate, and needs a
local daemon.

cmd/vaultik/lintdocker_test.go parses both Dockerfiles and both scripts
and fails if any part of the mechanism is dropped: the digest pin, the
defaultless ARG below `go mod download`, the emptiness guard, the
expansion of the epoch into each check command, the bare per-invocation
epoch assignment in both scripts, cibuild building both files, the
config verification running before the lint, and -- structurally, not
by searching for one retired variable name -- that no script invokes
golangci-lint except through docker. Every one of those losses is
silent: the build still exits 0 and nothing is checked, which is why
they are asserted rather than trusted. The scanner behind the last of
those has its own test, because a structural check that goes blind
passes on every tree, including a broken one.

script/lint takes no arguments now, and says so instead of dropping
them: a build step has no command line to pass linter flags to.
2026-08-10 13:38:45 +00:00

85 lines
3.6 KiB
Docker

# This file has no lint stage, deliberately.
#
# Linting lives in Dockerfile.lint, built by script/lint, and
# script/cibuild builds both. A lint stage here would have to either
# shell out to `make lint` -- which is now `docker build`, so
# docker-in-docker inside a BuildKit step with no daemon -- or call
# golangci-lint directly, which would mean a second, independently
# bumpable digest pin for the linter alongside the one in
# Dockerfile.lint. Two pins for one tool is the drift that
# https://git.eeqj.de/sneak/vaultik/issues/78 was filed over. See
# https://git.eeqj.de/sneak/vaultik/issues/113 for the ruling.
#
# Consequence, stated rather than left to be discovered: script/docker
# builds this file only and therefore does not lint. `make fmt-check`
# and `make test` still run here, so what a green build of this file
# means is "formatted, tested, and it compiles" -- the lint verdict
# comes from script/lint or script/cibuild.
# Build stage
# golang:1.26.1-alpine, 2026-03-17
FROM golang:1.26.1-alpine@sha256:2389ebfa5b7f43eeafbd6be0c3700cc46690ef842ad962f6c5bd6be49ed82039 AS builder
ARG VERSION=dev
# Install build dependencies for CGO (mattn/go-sqlite3) and sqlite3 CLI (tests)
RUN apk add --no-cache make build-base sqlite
WORKDIR /src
# Copy go mod files first for better layer caching
COPY go.mod go.sum ./
RUN go mod download
# Copy source code
COPY . .
# Run the format check and the tests.
#
# CHECK_EPOCH must stay immediately above these RUNs. These layers are
# keyed on its value, so they are cache-eligible only for a value
# already built against this same tree. script/cibuild and script/docker
# each pass a fresh value on every invocation, which is what makes their
# green mean the checks really executed.
#
# The value is expanded into each check command rather than left to a
# bare declaration, so the cache miss does not depend on BuildKit's
# unreferenced-ARG handling staying as it is. It also puts the epoch in
# the build log, where a reader can see the layer was keyed fresh.
#
# The guard is what makes a build that omits --build-arg fail instead of
# lie. An unset ARG is an empty string, and an empty string is a
# perfectly stable cache key: without the guard the first such build
# runs the checks and every one after it on an unchanged tree replays
# these layers from cache, executes nothing, and still exits 0. Failed
# steps are never cached, so the guard fails on EVERY invocation rather
# than once -- a bare `docker build .` is a loud error, not a quiet
# green. Do not give CHECK_EPOCH a default value; a default would
# satisfy the guard with a constant and restore the hole.
#
# Everything above this line (apk, go.mod, `go mod download`) is
# deliberately outside the busted range and keeps caching.
ARG CHECK_EPOCH
RUN [ -n "$CHECK_EPOCH" ] || exit 1
RUN echo "check epoch: ${CHECK_EPOCH}" && make fmt-check
RUN echo "check epoch: ${CHECK_EPOCH}" && make test
# Build (pure Go, no CGO required since we use modernc.org/sqlite)
RUN CGO_ENABLED=0 go build -ldflags "-X 'sneak.berlin/go/vaultik/internal/globals.Version=${VERSION}' -X 'sneak.berlin/go/vaultik/internal/globals.Commit=$(git rev-parse HEAD 2>/dev/null || echo unknown)' -X 'sneak.berlin/go/vaultik/internal/globals.CommitDate=$(git show -s --format=%cs HEAD 2>/dev/null || echo unknown)'" -o /vaultik ./cmd/vaultik
# Runtime stage
# alpine:3.21, 2026-02-25
FROM alpine:3.21@sha256:c3f8e73fdb79deaebaa2037150150191b9dcbfba68b4a46d70103204c53f4709
RUN apk add --no-cache ca-certificates sqlite
# Copy binary from builder
COPY --from=builder /vaultik /usr/local/bin/vaultik
# Create non-root user
RUN adduser -D -H -s /sbin/nologin vaultik
USER vaultik
ENTRYPOINT ["/usr/local/bin/vaultik"]