add Helm chart release to GitHub Actions workflow

Signed-off-by: zeroalphat <taichi-takemura@cybozu.co.jp>

Author: zeroalphat

.github/workflows/release.yaml

@@ -60,3 +60,31 @@ jobs:
           gh release create $VERSION $PRERELEASE_FLAG \
             -t "Release $VERSION"  \
             --generate-notes 
+  chart-release:
+    permissions:
+      contents: write
+    runs-on: "ubuntu-24.04"
+    needs: release
+    if: contains(needs.release.result, 'success')
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - name: Create release notes
+        run: |
+          tag_version=${GITHUB_REF##*/}
+          cat <<EOF > ./charts/ofen/RELEASE.md
+          Helm chart for ofen [$tag_version](https://github.com/cybozu-go/ofen/releases/tag/$tag_version)
+
+          EOF
+      - name: Configure Git
+        run: |
+          git config user.name "$GITHUB_ACTOR"
+          git config user.email "$GITHUB_ACTOR@users.noreply.github.com"
+      - name: Run chart-releaser
+        uses: helm/chart-releaser-action@cae68fefc6b5f367a0275617c9f83181ba54714f # v1.7.0
+        with:
+          config: "cr.yaml"
+        env:
+          CR_TOKEN: "${{ secrets.GITHUB_TOKEN }}"

cr.yaml

@@ -0,0 +1,4 @@
+owner: cybozu-go
+git-repo: ofen
+release-name-template: "{{ .Name }}-chart-{{ .Version }}"
+release-notes-file: RELEASE.md