fix(ci): stop helm release PRs from piling up and going stale (#42209)

.github/workflows/superset-helm-release.yml

@@ -1,6 +1,9 @@
 # This workflow automates the release process for Helm charts.
-# The workflow creates a new branch for the release and opens a pull request against the 'gh-pages' branch,
-# allowing the changes to be reviewed and merged manually.
+# Each run force-recreates a single 'helm-publish' branch from the tip of 'gh-pages' and
+# opens (or reuses) one pull request against 'gh-pages', allowing the changes to be
+# reviewed and merged manually. Because chart-releaser rebuilds index.yaml from all
+# published GitHub releases, the branch always contains every chart released since the
+# last merge, and the PR can never go stale or conflict with gh-pages.
 
 name: "Helm: release charts"
 
@@ -18,6 +21,12 @@ on:
         required: false
         default: "master"
 
+# Serialize runs: concurrent runs would race on force-pushing the shared
+# helm-publish branch while chart-releaser is mid-release.
+concurrency:
+  group: helm-release
+  cancel-in-progress: false
+
 jobs:
   release:
     runs-on: ubuntu-26.04
@@ -57,9 +66,9 @@ jobs:
           echo "DEBUG TAGS"
           git show-ref --tags
 
-      - name: Create unique pages branch name
+      - name: Set pages branch name
         id: vars
-        run: echo "branch_name=helm-publish-${GITHUB_SHA:0:7}" >> $GITHUB_ENV
+        run: echo "branch_name=helm-publish" >> $GITHUB_ENV
 
       - name: Force recreate branch from gh-pages
         env:
@@ -97,12 +106,17 @@ jobs:
           version: v1.6.0
           charts_dir: helm
           mark_as_latest: false
+          # A helm/** change without a Chart.yaml version bump repackages the
+          # already-released version; without this, cr aborts on the existing
+          # release tag (422 already_exists) instead of proceeding to rebuild
+          # the index, and the whole run fails.
+          skip_existing: true
           pages_branch: ${{ env.branch_name }}
         env:
           CR_TOKEN: "${{ github.token }}"
           CR_RELEASE_NAME_TEMPLATE: "superset-helm-chart-{{ .Version }}"
 
-      - name: Open Pull Request
+      - name: Open or reuse Pull Request
         uses: actions/github-script@3a2844b7e9c422d3c10d287c895573f7108da1b3 # v9.0.0
         with:
           script: |
@@ -113,15 +127,72 @@ jobs:
               throw new Error("Branch name is not defined.");
             }
 
-            const pr = await github.rest.pulls.create({
+            // The branch is force-recreated from gh-pages on every run, so an
+            // already-open PR for it now reflects this run's charts; opening
+            // another would both fail (422) and recreate the stale-PR pileup
+            // this fixed branch exists to avoid.
+            const { data: existing } = await github.rest.pulls.list({
               owner,
               repo,
-              title: `Helm chart release for ${branchName}`,
-              head: branchName,
-              base: "gh-pages", // Adjust if the target branch is different
-              body: `This PR releases Helm charts to the gh-pages branch.`,
+              state: "open",
+              head: `${owner}:${branchName}`,
+              base: "gh-pages",
             });
 
-            core.info(`Pull request created: ${pr.data.html_url}`);
+            let current;
+            if (existing.length > 0) {
+              current = existing[0];
+              core.info(`Reusing existing pull request: ${current.html_url}`);
+            } else {
+              const { data: pr } = await github.rest.pulls.create({
+                owner,
+                repo,
+                title: "Helm chart release",
+                head: branchName,
+                base: "gh-pages", // Adjust if the target branch is different
+                body: [
+                  "This PR releases Helm charts to the gh-pages branch.",
+                  "",
+                  "It is force-updated from the tip of `gh-pages` by every release run,",
+                  "so it always contains every chart released since the last merge and",
+                  "never needs to be closed as superseded.",
+                ].join("\n"),
+              });
+              current = pr;
+              core.info(`Pull request created: ${current.html_url}`);
+            }
+
+            // Sweep release PRs left open by older runs (per-SHA helm-publish-*
+            // branches from the previous scheme). Their content is a subset of
+            // the evergreen PR, so close them with a pointer to it.
+            const { data: openPrs } = await github.rest.pulls.list({
+              owner,
+              repo,
+              state: "open",
+              base: "gh-pages",
+              per_page: 100,
+            });
+
+            for (const stale of openPrs) {
+              if (
+                stale.number !== current.number &&
+                stale.head.repo?.full_name === process.env.GITHUB_REPOSITORY &&
+                stale.head.ref.startsWith("helm-publish")
+              ) {
+                await github.rest.issues.createComment({
+                  owner,
+                  repo,
+                  issue_number: stale.number,
+                  body: `Superseded by #${current.number}, which now carries all unreleased charts. Closing.`,
+                });
+                await github.rest.pulls.update({
+                  owner,
+                  repo,
+                  pull_number: stale.number,
+                  state: "closed",
+                });
+                core.info(`Closed superseded release PR #${stale.number}`);
+              }
+            }
         env:
           BRANCH_NAME: ${{ env.branch_name }}