feat: post CI results in PRs

Signed-off-by: avivkeller <me@aviv.sh>

Author: avivkeller

lib/jenkins-ci-results.js

@@ -0,0 +1,54 @@
+import { Writable } from 'node:stream'
+
+import CLI from 'node-core-utils/lib/cli.js'
+import Request from 'node-core-utils/lib/request.js'
+import { PRBuild } from 'node-core-utils/lib/ci/build-types/pr_build.js'
+
+import { createPrComment } from './github-comment.js'
+
+export function extractBuildNumber (build) {
+  // e.g. https://ci.nodejs.org/job/node-test-pull-request/21633/
+  const match = /\/job\/node-test-pull-request\/(\d+)/.exec(build.url || '')
+  return match ? parseInt(match[1], 10) : null
+}
+
+export async function fetchResultsMarkdown (buildNumber) {
+  // node-core-utils insists on writing progress output to a stream
+  const nullStream = new Writable({ write (chunk, encoding, callback) { callback() } })
+  const cli = new CLI(nullStream)
+  const request = new Request({
+    jenkins: Buffer.from(process.env.JENKINS_API_CREDENTIALS).toString('base64')
+  })
+
+  const prBuild = new PRBuild(cli, request, buildNumber)
+  await prBuild.getResults()
+  return prBuild.formatAsMarkdown()
+}
+
+export async function postBuildResults (options, build, fetchResults = fetchResultsMarkdown) {
+  const { pr } = options
+  const buildNumber = extractBuildNumber(build)
+
+  const traceFields = { pr, job: build.identifier, gitRef: build.ref, buildNumber }
+  const logger = options.logger.child(traceFields, true)
+
+  if (!process.env.JENKINS_API_CREDENTIALS) {
+    logger.info('JENKINS_API_CREDENTIALS is not set, skipping CI results comment')
+    return
+  }
+
+  if (buildNumber === null) {
+    logger.warn('Unable to find build number in build URL, skipping CI results comment')
+    return
+  }
+
+  const markdown = await fetchResults(buildNumber)
+
+  if (!markdown) {
+    logger.warn('Got no CI results back from node-core-utils, skipping CI results comment')
+    return
+  }
+
+  await createPrComment({ issue_number: pr, ...options, logger }, markdown)
+  logger.info('Jenkins CI results comment posted')
+}

lib/push-jenkins-update.js

@@ -1,5 +1,6 @@
 import githubClient from './github-client.js'
 import { createPrComment } from './github-comment.js'
+import { postBuildResults } from './jenkins-ci-results.js'
 
 export function pushStarted (options, build, cb) {
   const pr = findPrInRef(build.ref)
@@ -54,6 +55,14 @@ export function pushEnded (options, build, cb) {
 
   const optsWithPr = Object.assign({ pr }, options)
 
+  if (build.identifier === 'node-test-pull-request') {
+    // fetching the CI results involves many Jenkins API calls, so let them
+    // finish in the background instead of holding up the status update
+    postBuildResults(optsWithPr, build).catch((err) => {
+      logger.error(err, 'Error while posting Jenkins CI results')
+    })
+  }
+
   findLatestCommitInPr(optsWithPr).then(latestCommit => {
     const statusOpts = Object.assign({
       sha: latestCommit.sha,