Add attestation to releases

.github/workflows/release.yml

@@ -7,53 +7,41 @@ on: # yamllint disable rule:truthy
       - "*.*.*"
 
 jobs:
-  pkg:
-    runs-on: ubuntu-latest
-
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v6
-
-      - name: Create release archive and notes
-        # Set by GH actions, see
-        # https://docs.github.com/en/actions/learn-github-actions/environment-variables#default-environment-variables
-        run: ./ci/package.sh "${{ github.ref_name }}"
-
-      - name: Archive release artifacts
-        uses: actions/upload-artifact@v6
-        with:
-          name: release
-          path: release/*
-          retention-days: 5
-
+  # Delegate the release archive build + attestation + GitHub release
+  # creation to the bazel-contrib reusable workflow. BCR's verifier
+  # only trusts attestations whose builder ID matches this reusable
+  # workflow path; rolling our own actions/attest-build-provenance
+  # would produce a valid SLSA attestation that BCR would still reject.
+  #
+  # The reusable workflow calls .github/workflows/release_prep.sh
+  # (hardcoded path) with the tag as $1, expects release notes on
+  # stdout, and expects release_files to be produced in cwd.
   release:
-    runs-on: ubuntu-latest
     permissions:
       contents: write
-    needs: pkg
-    steps:
-      - name: Download release artifacts
-        uses: actions/download-artifact@v7
-        with:
-          name: release
-
-      - name: Release
-        uses: softprops/action-gh-release@v2
-        with:
-          generate_release_notes: true
-          body_path: release_notes.md
-          fail_on_unmatched_files: true
-          files: rules_shellcheck-*.tar.gz
+      # id-token: write + attestations: write let the reusable
+      # workflow run actions/attest-build-provenance and attach a
+      # BCR-trusted SLSA attestation to the release.
+      id-token: write
+      attestations: write
+    uses: bazel-contrib/.github/.github/workflows/release_ruleset.yaml@v7.6.0
+    with:
+      release_files: rules_shellcheck-*.tar.gz
+      prerelease: false
+      tag_name: ${{ github.ref_name }}
 
   bcr-publish:
     needs: [release]
     uses: bazel-contrib/publish-to-bcr/.github/workflows/publish.yaml@v1.1.0
     permissions:
       contents: write
+      # Propagate id-token: write + attestations: write so the
+      # reusable publish workflow can read the release's attestation
+      # and re-attest the BCR entry files.
       id-token: write
       attestations: write
     with:
-      tag_name: ${{ needs.release.outputs.release_version }}
+      tag_name: ${{ github.ref_name }}
       registry_fork: aignas/bazel-central-registry
       author_name: aignas
       author_email: 240938+aignas@users.noreply.github.com

.github/workflows/release_prep.sh

@@ -0,0 +1,35 @@
+#!/usr/bin/env bash
+# Build the rules_shellcheck release archive and emit release notes.
+# Invoked by bazel-contrib/.github/.github/workflows/release_ruleset.yaml
+# at the hardcoded path `.github/workflows/release_prep.sh`.
+#
+# Args:
+#   $1: tag name (e.g. 0.4.0). Passed through as the --embed_label
+#       value so the archive is stamped with the release version.
+#
+# Side effects:
+#   Writes rules_shellcheck-${TAG}.tar.gz to the current directory —
+#   the location the `release_files` glob in release.yml expects.
+#
+# Output:
+#   Release notes to stdout. The reusable workflow redirects stdout
+#   into release_notes.txt for the GitHub release body; every other
+#   line goes to stderr so it doesn't pollute the notes.
+
+set -euo pipefail
+
+# Redirect stdout to stderr; keep fd 3 for the final release-notes write.
+exec 3>&1 1>&2
+
+TAG="${1:?tag_name required}"
+
+# Reuse the existing //:release target — same tarball and rendered
+# notes that ci/package.sh produces for PR validation, minus the
+# example-validation loop (release_ruleset already runs bazel test).
+bazel run --stamp --embed_label "${TAG}" //:release -- release
+
+# //:release writes into ./release/; move the archive up so the
+# `release_files: rules_shellcheck-*.tar.gz` glob picks it up.
+mv "release/rules_shellcheck-${TAG}.tar.gz" .
+
+cat "release/release_notes.md" >&3