Add Quick Access to images comment to PRs (#1133)

* Add Quick Access to images comment to PRs

* Refactor Image comment workflow to use shared script pattern.

Also refactors away dead crud.

* Refine comment output and normalise names to prevent bugs.

* Fix PR comment writing not working.

* Please the linter

* Remove Sha Tag due to it going stale if any branch movement happens.

Author: FSG-Cat

.github/scripts/pr-ghcr-image-comment.js

@@ -0,0 +1,86 @@
+// SPDX-FileCopyrightText: 2026 Catalan Lover <catalanlover@protonmail.com>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+/**
+ * @param {Object} args
+ * @param {import('@actions/github').getOctokit} args.github
+ * @param {import('@actions/github').context} args.context
+ * @param {import('@actions/core')} args.core
+ */
+module.exports = async ({ github, context, core }) => {
+  const pullRequest = context.payload.pull_request;
+  if (!pullRequest) {
+    core.notice("No pull_request payload found; skipping.");
+    return;
+  }
+
+  const marker = "<!-- ghcr-pr-image-link -->";
+  const repo = context.repo.repo;
+  const ownerContext = context.repo.owner;
+  const prNumber = pullRequest.number;
+
+  // prOwner is a bit confusingly named it could be argued. Its Head Branch Owner effectively.
+  // It is used to determine the GHCR namespace for the PR build.
+  // In most cases this will be the same as the repo owner,
+  // but in fork scenarios it will be different and we want to ensure the GHCR namespace is correct,
+  // to keep this workflow functional for its intended purpose of providing image refs for PRs independently of origin.
+  const prOwner = pullRequest.head?.repo?.owner?.login || ownerContext;
+  const branch = pullRequest.head?.ref || "";
+  const sha = pullRequest.head?.sha || context.sha;
+  const shortSha = sha.substring(0, 7);
+  const normalizedBranch = branch.replace(/\//g, "-");
+
+  const lowerOwner = prOwner.toLowerCase();
+  const lowerRepo = repo.toLowerCase();
+
+  const imageNamespace = `ghcr.io/${lowerOwner}/${lowerRepo}`;
+  // The root package URL on GitHub. We can't link to the exact version ID without querying the GH API,
+  // so we link to the package landing page where the user can see the recent tags.
+  const packageUrl = `https://github.com/${prOwner}/${repo}/pkgs/container/${lowerRepo}`;
+
+  const branchTag = normalizedBranch || shortSha;
+
+  const body = [
+    `GHCR image refs for this PR:`,
+    "",
+    `- Namespace: \`${imageNamespace}\``,
+    `- Branch tag: \`${branchTag}\``,
+    `- Package Page: [GHCR Link](${packageUrl})`,
+    `- Pull: \`docker pull ${imageNamespace}:${branchTag}\``,
+    "",
+    `This comment is generated from PR metadata only. It does not checkout or run PR code and is generated in a static manner`,
+    marker,
+  ].join("\n");
+
+  // Update or create comments
+  const comments = await github.rest.issues.listComments({
+    owner: ownerContext,
+    repo,
+    issue_number: prNumber,
+    per_page: 100,
+  });
+
+  const existingComment = comments.data.find(
+    (comment) =>
+      comment.user?.type === "Bot" &&
+      typeof comment.body === "string" &&
+      comment.body.includes(marker)
+  );
+
+  if (existingComment) {
+    await github.rest.issues.updateComment({
+      owner: ownerContext,
+      repo,
+      comment_id: existingComment.id,
+      body,
+    });
+  } else {
+    await github.rest.issues.createComment({
+      owner: ownerContext,
+      repo,
+      issue_number: prNumber,
+      body,
+    });
+  }
+};

.github/workflows/pr-ghcr-image-comment-opened.yml

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+# SPDX-FileCopyrightText: 2026 Catalan Lover <catalanlover@protonmail.com>
+#
+# SPDX-License-Identifier: Apache-2.0
+
+name: "PR - GHCR Image Link (Opened)"
+
+on:
+  pull_request_target:
+    types: [opened, synchronize, reopened]
+
+permissions:
+  issues: write
+  pull-requests: write
+
+jobs:
+  comment-pr:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
+
+      - name: Comment on the pull request
+        uses: actions/github-script@3a2844b7e9c422d3c10d287c895573f7108da1b3
+        with:
+          script: |
+            const script = require('./.github/scripts/pr-ghcr-image-comment.js');
+            await script({ github, context, core });