fix(workflows): test ci with pull_request_target (aws#5508)

## Problem
Just logging the changelog/test notification isn't really a good way

## Solution
Revert aws#5506 in favour of trying out pull_request_target. pull_request_target gives us these extra permissions to create these workflows that comment on PR's. I've also moved notification out of the lint so its non-critical path

Example run: jpinkney-aws#269

---

<!--- REMINDER: Ensure that your PR meets the guidelines in
CONTRIBUTING.md -->

License: I confirm that my contribution is made under the terms of the
Apache 2.0 license.

Author: jpinkney-aws

.github/workflows/node.js.yml

@@ -32,13 +32,6 @@ jobs:
             - uses: actions/setup-node@v4
               with:
                   node-version: '20'
-            - name: Check for tests
-              uses: actions/github-script@v7
-              with:
-                  script: |
-                      const notify = require('.github/workflows/notify.js')
-                      await notify({github, context})
-              if: github.event_name == 'pull_request'
             - name: Check PR title
               run: |
                   node "$GITHUB_WORKSPACE/.github/workflows/lintcommit.js"

.github/workflows/notification.yml

@@ -0,0 +1,42 @@
+# github actions: https://docs.github.com/en/actions/use-cases-and-examples/building-and-testing/building-and-testing-nodejs
+# setup-node: https://github.com/actions/setup-node
+
+name: Notifications
+
+on:
+    pull_request_target:
+        branches: [master, feature/*, staging]
+        # Default = opened + synchronize + reopened.
+        # We also want "edited" so that changelog notifications runs when PR title is updated.
+        # https://docs.github.com/en/actions/writing-workflows/choosing-when-your-workflow-runs/events-that-trigger-workflows#pull_request
+        types:
+            - edited
+            - opened
+            - reopened
+            - synchronize
+
+# Cancel old jobs when a pull request is updated.
+concurrency:
+    group: ${{ github.workflow }}-${{ github.ref }}
+    cancel-in-progress: true
+
+jobs:
+    notify:
+        runs-on: ubuntu-latest
+        permissions:
+            pull-requests: write
+            issues: read
+        steps:
+            - uses: actions/checkout@v4
+              with:
+                  fetch-depth: 20
+            - uses: actions/setup-node@v4
+              with:
+                  node-version: '20'
+            - name: Check for tests
+              uses: actions/github-script@v7
+              with:
+                  script: |
+                      const notify = require('.github/workflows/notify.js')
+                      await notify({github, context})
+              if: github.event_name == 'pull_request_target'

.github/workflows/notify.js

@@ -3,7 +3,7 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-const { parsePRTitle, hasPath } = require('./utils')
+const { parsePRTitle, hasPath, dedupComment } = require('./utils')
 
 const testFilesMessage =
     'This pull request modifies files in src/ but no tests were added/updated. Confirm whether tests should be added or ensure the PR description explains why tests are not required.'
@@ -21,6 +21,7 @@ module.exports = async ({ github, context }) => {
     const owner = context.repo.owner
     const repo = context.repo.repo
     const author = context.payload.pull_request.head.repo.owner.login
+    const pullRequestId = context.payload.pull_request.number
 
     const response = await github.rest.repos.compareCommitsWithBasehead({
         owner,
@@ -37,13 +38,19 @@ module.exports = async ({ github, context }) => {
         return
     }
 
+    // Check for prior comments on the PR
+    const comments = await github.rest.issues.listComments({
+        owner,
+        repo,
+        issue_number: pullRequestId,
+    })
+
     if (shouldAddTestFileMessage) {
-        // We can't really block on this one, since its valid to make a change in src/ without adding tests :(        console.error(testFilesMessage)
+        await dedupComment({ github, comments, owner, repo, pullRequestId, message: testFilesMessage })
     }
 
     if (shouldAddChangelogMessage) {
-        console.error(changelogMessage)
-        process.exit(1)
+        await dedupComment({ github, comments, owner, repo, pullRequestId, message: changelogMessage })
     }
 }
 

.github/workflows/utils.js

@@ -25,6 +25,22 @@ function parsePRTitle(title) {
     }
 }
 
+/**
+ * Create a comment on a PR if one does not already exist
+ */
+async function dedupComment({ github, pullRequestId, owner, repo, comments, message }) {
+    if (comments.data.some((comment) => comment.body.includes(message))) {
+        return
+    }
+
+    await github.rest.issues.createComment({
+        issue_number: pullRequestId,
+        owner,
+        repo,
+        body: message,
+    })
+}
+
 /*
  * Check if path is included in at least one of the filename paths
  */
@@ -34,5 +50,6 @@ function hasPath(filenames, path) {
 
 module.exports = {
     parsePRTitle,
+    dedupComment,
     hasPath,
 }