chore: fix issue labeler (vercel#47206)

### What?

A fork of https://github.com/github/issue-labeler that we pull in and
maintain.

### Why?

The official issue labeler had some issues which I tried to fix in PRs
and eventually got merged upstream, but the release cycle was a bit
slow, and that GitHub action had many parts we did not really need
anyway. So it makes sense to maintain it ourselves.

### How?

This PR removes the
https://github.com/vercel/next.js/blob/canary/.github/issue-labeler.yml
config file, which in our case is just a sublist of
https://github.com/vercel/next.js/labels anyway. Instead, we can pull in
the labels from GitHub directly and filter out those that we want to
apply to issues. This will keep things more in sync.

fix NEXT-750 ([link](https://linear.app/vercel/issue/NEXT-750))

---------

.eslintignore

@@ -20,6 +20,7 @@ packages/react-dev-overlay/lib/**
 **/__tmp__/**
 .github/actions/next-stats-action/.work
 .github/actions/issue-validator/index.mjs
+.github/actions/issue-labeler/lib/index.js
 packages/next-codemod/transforms/__testfixtures__/**/*
 packages/next-codemod/transforms/__tests__/**/*
 packages/next-codemod/**/*.js

.github/actions/issue-labeler/.gitignore

@@ -0,0 +1 @@
+node_modules/

.github/actions/issue-labeler/lib/package.json

@@ -0,0 +1,3 @@
+{
+  "type": "module"
+}

.github/actions/issue-labeler/package.json

@@ -0,0 +1,18 @@
+{
+  "private": true,
+  "name": "issue-labeler",
+  "type": "module",
+  "exports": "./lib/index.js",
+  "scripts": {
+    "build": "pnpm types && pnpm ncc -m -o ./lib build src/index.ts --license licenses.txt",
+    "types": "tsc"
+  },
+  "dependencies": {
+    "@actions/core": "^1.10.0",
+    "@actions/github": "^5.1.1"
+  },
+  "devDependencies": {
+    "@types/node": "^18.15.3",
+    "@vercel/ncc": "0.36.1"
+  }
+}

.github/actions/issue-labeler/src/index.ts

@@ -0,0 +1,102 @@
+import { setFailed, debug } from '@actions/core'
+import { context, getOctokit } from '@actions/github'
+
+type GitHubClient = ReturnType<typeof getOctokit>['rest']
+
+async function run() {
+  const token = process.env.GITHUB_TOKEN
+  if (!token) throw new Error('No GITHUB_TOKEN provided')
+
+  const { issue } = context.payload
+  if (!issue) return console.log('Not an issue, exiting')
+
+  const { body: issue_body, number: issue_number, title: issue_title } = issue
+  if (!issue_number) return console.log('Could not get issue number, exiting')
+  if (!issue_body) return console.log('Could not get issue body, exiting')
+  if (!issue_title) return console.log('Could not get issue title, exiting')
+
+  // A client to load data from GitHub
+  const { rest: client } = getOctokit(token)
+
+  // Load our regex rules from the repo labels
+  const labels = await loadAreaLabels(client)
+
+  debug(`Loaded labels: ${Array.from(labels.keys()).join(', ')}`)
+
+  /** List of labels to add */
+  const toAdd: string[] = []
+
+  // https://github.com/vercel/next.js/blame/canary/.github/ISSUE_TEMPLATE/1.bug_report.yml
+
+  const matchSection = issue_body
+    .split('Which area(s) of Next.js are affected? (leave empty if unsure)')[1]
+    ?.split('Link to the code that reproduces this issue')[0]
+
+  if (!matchSection) {
+    console.log(
+      `Issue #${issue_number} does not contain a match section, likely not a bug template, exiting`
+    )
+    return
+  }
+
+  debug(`Match section: ${matchSection}`)
+
+  for (const [label, description] of labels.entries()) {
+    if (matchSection.includes(description)) {
+      toAdd.push(label)
+    }
+  }
+
+  debug(`Labels to add: ${toAdd.join(', ')}`)
+
+  if (!toAdd.length) return console.log('No labels to add, exiting')
+
+  await addLabels(client, issue_number, toAdd)
+
+  debug(`Added labels to issue #${issue_number}: ${toAdd.join(', ')}`)
+}
+
+/** Load label descriptions from the repo. */
+async function loadAreaLabels(client: GitHubClient) {
+  try {
+    const { data } = await client.issues.listLabelsForRepo({
+      owner: context.repo.owner,
+      repo: context.repo.repo,
+      per_page: 100,
+    })
+
+    const labels = new Map<string, string>()
+    // Only load labels that start with `area:` and have a description
+    for (const label of data) {
+      if (label.name.startsWith('area:') && label.description) {
+        labels.set(label.name, label.description)
+      }
+    }
+    return labels
+  } catch (error) {
+    console.error('Error loading labels: ' + error)
+    throw error
+  }
+}
+
+async function addLabels(
+  client: GitHubClient,
+  issue_number: number,
+  labels: string[]
+) {
+  try {
+    const formatted = labels.map((l) => `"${l}"`).join(', ')
+    debug(`Adding label(s) (${formatted}) to issue #${issue_number}`)
+    return await client.issues.addLabels({
+      owner: context.repo.owner,
+      repo: context.repo.repo,
+      issue_number,
+      labels,
+    })
+  } catch (error) {
+    console.error(`Could not add label(s) ${labels} to issue #${issue_number}`)
+    throw error
+  }
+}
+
+run().catch(setFailed)

.github/actions/issue-labeler/tsconfig.json

@@ -0,0 +1,10 @@
+{
+  "compilerOptions": {
+    "noEmit": true,
+    "target": "esnext",
+    "moduleResolution": "node",
+    "rootDir": "./src",
+    "strict": true,
+    "noImplicitAny": true
+  }
+}

.github/workflows/issue_labeler.yml

@@ -13,9 +13,10 @@ jobs:
     name: Triage
     runs-on: ubuntu-latest
     steps:
-      - uses: github/issue-labeler@v3.0
+      - uses: actions/setup-node@v3
         with:
-          repo-token: '${{ secrets.GITHUB_TOKEN }}'
-          configuration-path: '.github/issue-labeler.yml'
-          enable-versioned-regex: 0
-          sync-labels: 0
+          node-version: 18
+      - name: 'Run issue labeler'
+        run: node ./.github/actions/issue-labeler/lib
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.prettierignore

@@ -12,6 +12,7 @@ packages/react-dev-overlay/lib/**
 lerna.json
 .github/actions/next-stats-action/.work
 .github/actions/issue-validator/index.mjs
+.github/actions/issue-labeler/lib/index.js
 packages/next-swc/crates/**/*
 packages/next-swc/target/**/*
 packages/next-swc/native/**/*