release.yaml

name: Release

on:
  push:
    tags:
      - "v*"

permissions:
  contents: write

jobs:
  release:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v7
        with:
          fetch-depth: 0

      - name: Set up Go
        uses: actions/setup-go@v7
        with:
          go-version-file: src/go.mod

      # The workshop ships a single moving v0.3.0 tag, so each tag move
      # re-releases onto the same GitHub release. GitHub ties a release to the
      # tag *name*, not the commit, so the release object survives a tag move
      # with its old assets attached. GoReleaser's `release.mode: replace`
      # only clears assets when it recreates the release (e.g. a draft); on a
      # reused *published* release it leaves the old assets in place and the
      # upload then fails with "already_exists" (HTTP 422). So we delete the
      # tag's existing release assets here, right before GoReleaser uploads the
      # new ones. This is a controlled re-release (binaries rebuild in minutes),
      # not an automatic push, so the brief window with no downloadable asset is
      # acceptable; relying on `mode: replace` alone fails every time GitHub
      # reuses the release. The release object itself is left
      # in place, so there is never a 404 on the release, only a short gap in
      # its assets while GoReleaser re-uploads.
      - name: Clear existing release assets for this tag
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          TAG: ${{ github.ref_name }}
        run: |
          release_id=$(gh api --paginate "repos/$GITHUB_REPOSITORY/releases" \
            --jq ".[] | select(.tag_name == \"$TAG\" and .draft == false) | .id" \
            | head -n1)
          if [ -z "$release_id" ]; then
            echo "No published release for $TAG yet; nothing to clear."
            exit 0
          fi
          echo "Clearing assets on release $release_id for $TAG"
          gh api --paginate "repos/$GITHUB_REPOSITORY/releases/$release_id/assets" \
            --jq '.[].id' \
          | while read -r asset_id; do
              echo "Deleting asset $asset_id"
              gh api -X DELETE "repos/$GITHUB_REPOSITORY/releases/assets/$asset_id"
            done

      - name: Run GoReleaser
        uses: goreleaser/goreleaser-action@v7
        with:
          version: "~> v2"
          args: release --clean
          workdir: src
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

      # Because v0.3.0 is a moving tag, GitHub allows only one *published*
      # release per tag: when this run publishes its release, GitHub demotes the
      # tag's previous release to a draft rather than deleting it, so drafts
      # accumulate one per release. Delete every draft release for this tag,
      # keeping the just-published one. Runs after GoReleaser so the published
      # release always exists first (no empty window). Deletes the release
      # object only, never the git tag.
      - name: Remove stale draft releases for this tag
        if: success()
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          TAG: ${{ github.ref_name }}
        run: |
          gh api --paginate "repos/$GITHUB_REPOSITORY/releases" \
            --jq ".[] | select(.tag_name == \"$TAG\" and .draft == true) | .id" \
          | while read -r id; do
              echo "Deleting stale draft release $id for $TAG"
              gh api -X DELETE "repos/$GITHUB_REPOSITORY/releases/$id" || true
            done