1name: Comment on pull request
 2on:
 3  workflow_run:
 4    workflows: [build]
 5    types: [completed]
 6jobs:
 7  pr_comment:
 8    if: github.event.workflow_run.event == 'pull_request' && github.event.workflow_run.conclusion == 'success'
 9    runs-on: ubuntu-latest
10    steps:
11      - uses: actions/github-script@v5
12        with:
13          # This snippet is public-domain, taken from
14          # https://github.com/oprypin/nightly.link/blob/master/.github/workflows/pr-comment.yml
15          script: |
16            async function upsertComment(owner, repo, issue_number, purpose, body) {
17              const {data: comments} = await github.rest.issues.listComments(
18                {owner, repo, issue_number});
19
20              const marker = `<!-- bot: ${purpose} -->`;
21              body = marker + "\n" + body;
22
23              const existing = comments.filter((c) => c.body.includes(marker));
24              if (existing.length > 0) {
25                const last = existing[existing.length - 1];
26                core.info(`Updating comment ${last.id}`);
27                await github.rest.issues.updateComment({
28                  owner, repo,
29                  body,
30                  comment_id: last.id,
31                });
32              } else {
33                core.info(`Creating a comment in issue / PR #${issue_number}`);
34                await github.rest.issues.createComment({issue_number, body, owner, repo});
35              }
36            }
37
38            const {owner, repo} = context.repo;
39            const run_id = ${{github.event.workflow_run.id}};
40
41            const pull_requests = ${{ toJSON(github.event.workflow_run.pull_requests) }};
42            if (!pull_requests.length) {
43              return core.error("This workflow doesn't match any pull requests!");
44            }
45
46            const artifacts = await github.paginate(
47              github.rest.actions.listWorkflowRunArtifacts, {owner, repo, run_id});
48            if (!artifacts.length) {
49              return core.error(`No artifacts found`);
50            }
51            const sha = "${{github.event.workflow_run.head_sha}}";
52            let body = `Download the artifacts for this pull request:\n`;
53            for (const art of artifacts) {
54              body += `\n* [${art.name}.zip](https://nightly.link/${owner}/${repo}/actions/artifacts/${art.id}.zip)`;
55            }
56            body += `\n\nOr use the following Docker image \`ghcr.io/${owner}/${repo}:devel-${sha.substr(0,7)}\``;
57
58            core.info("Review thread message body:", body);
59
60            for (const pr of pull_requests) {
61              await upsertComment(owner, repo, pr.number,
62                "nightly-link", body);
63            }