release: reject dirty sources and build artifacts

Fixes #3583

.github/workflows/release-check.yml

@@ -0,0 +1,35 @@
+name: Release checks
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+defaults:
+  run:
+    shell: nix develop --fallback --command bash -e {0}
+
+jobs:
+  release-check:
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          fetch-depth: 0
+      - uses: NixOS/nix-installer-action@62c1943b776c509394b550f3f983adc14e9212d6 # main
+      - uses: Mic92/hestia@dfed9ced335d28978ba74e513939a10db1f71025 # v3.1.0
+      - name: Validate release configuration
+        run: goreleaser check
+      - name: Test release guards
+        run: bash tools/release-check-test.sh
+      - name: Build and verify Headscale release binary
+        run: goreleaser build --snapshot --clean --single-target

.goreleaser.yml

@@ -2,7 +2,6 @@
 version: 2
 before:
   hooks:
-    - go mod tidy
     - go mod vendor
 
 release:
@@ -27,6 +26,9 @@ builds:
       - linux_arm64
     flags:
       - -mod=readonly
+    hooks:
+      pre: bash tools/release-check.sh
+      post: bash tools/release-check.sh "{{ .Path }}"
 
 archives:
   - id: golang-cross

tools/release-check-test.sh

@@ -0,0 +1,84 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+root=$(cd "$(dirname "$0")/.." && pwd)
+tmp=$(mktemp -d)
+trap 'rm -rf "$tmp"' EXIT
+export GOWORK=off CGO_ENABLED=0 LC_ALL=C
+unset GOFLAGS GOOS GOARCH
+
+mkdir -p "$tmp/headscale/cmd/headscale" "$tmp/headscale/tools"
+cp "$root/.goreleaser.yml" "$tmp/headscale/"
+cp "$root/tools/release-check.sh" "$tmp/headscale/tools/"
+cd "$tmp/headscale"
+cat > go.mod <<'MOD'
+module example.com/headscale
+
+go 1.24.0
+
+// Tidy removes this block, reproducing release-time go.mod edits.
+require (
+)
+MOD
+printf 'package main\nfunc main() {}\n' > cmd/headscale/main.go
+printf 'dist/\nvendor/\n' > .gitignore
+git init -q
+git config user.name 'Release check test'
+git config user.email 'release-check@example.invalid'
+git remote add origin https://github.com/juanfont/headscale.git
+git add .
+git commit -qm 'Create release fixture'
+git tag v0.0.1
+check="$PWD/tools/release-check.sh"
+
+expect_failure() {
+    local label=$1 message=$2
+    shift 2
+    if "$@" > "$tmp/failure.log" 2>&1; then
+        printf 'FAIL: %s unexpectedly succeeded\n' "$label" >&2
+        exit 1
+    fi
+    if ! grep -Fq "$message" "$tmp/failure.log"; then
+        cat "$tmp/failure.log" >&2
+        exit 1
+    fi
+    printf 'PASS: %s\n' "$label"
+}
+
+# Use the real release hooks and every configured target, without publishing.
+if ! goreleaser build --snapshot --clean > "$tmp/build.log" 2>&1; then
+    cat "$tmp/build.log" >&2
+    exit 1
+fi
+binaries=(dist/headscale_*/headscale)
+bash "$check" "${binaries[@]}"
+printf 'PASS: clean release builds, including cross-compiled binaries\n'
+
+git config status.showUntrackedFiles no
+printf '// dirty\n' >> cmd/headscale/main.go
+expect_failure 'unstaged change' 'working tree is dirty' bash "$check"
+go build -o dist/dirty ./cmd/headscale
+git add cmd/headscale/main.go
+expect_failure 'staged change' 'working tree is dirty' bash "$check"
+git restore --staged --worktree cmd/headscale/main.go
+expect_failure 'dirty binary after source cleanup' 'lacks clean VCS metadata' bash "$check" dist/dirty
+
+touch untracked
+expect_failure 'untracked file despite Git display settings' 'working tree is dirty' bash "$check"
+rm untracked
+
+go build -buildvcs=false -o dist/unstamped ./cmd/headscale
+expect_failure 'missing VCS metadata' 'lacks clean VCS metadata' bash "$check" dist/unstamped
+expect_failure 'missing binary' 'no such file or directory' bash "$check" dist/missing
+
+git commit --allow-empty -qm 'Advance fixture HEAD'
+expect_failure 'binary from another commit' 'was not built from HEAD' bash "$check" "${binaries[0]}"
+
+# Reintroducing a mutating preparation hook must abort the actual build pipeline.
+sed -i '/    - go mod vendor/a\    - go mod tidy' .goreleaser.yml
+git add .goreleaser.yml
+git commit -qm 'Reproduce release-time tidy'
+expect_failure 'preparation dirties source' 'working tree is dirty' goreleaser build --snapshot --clean --single-target
+
+cd "$tmp"
+expect_failure 'Git failure' 'not a git repository' bash "$check"

tools/release-check.sh

@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+status=$(git status --porcelain --untracked-files=all)
+if [[ -n "$status" ]]; then
+    printf 'release: working tree is dirty\n%s\n' "$status" >&2
+    exit 1
+fi
+
+for binary in "$@"; do
+    info=$(go version -m "$binary")
+    if ! grep -Eq '[[:space:]]vcs.modified=false$' <<< "$info"; then
+        printf 'release: %s lacks clean VCS metadata\n%s\n' "$binary" "$info" >&2
+        exit 1
+    fi
+    revision=$(git rev-parse HEAD)
+    if ! grep -Eq "[[:space:]]vcs.revision=${revision}$" <<< "$info"; then
+        printf 'release: %s was not built from HEAD\n%s\n' "$binary" "$info" >&2
+        exit 1
+    fi
+done