Auto label PRs that change docs, then auto assign tech writers (#5059)

* save

* detect doc changes

* create workflow to add label to PRs that change docs

* assign techwriters to labeled PRs

* update workflow name

* update command

* trigger workflow for testing

* fix bug

* update node version

* add missing import

* test

* revert change for testing

* update action version

* update version

* pass github token

* uppercase

* secrets

* fix workflow

* fix syntax

* use a different GHA

* downgrade

* format

* rename file

Author: Feiyang1

.github/auto_assign.yml

@@ -0,0 +1,26 @@
+# Set to true to add reviewers to pull requests
+addReviewers: false
+
+# Set to true to add assignees to pull requests
+addAssignees: true
+
+# A list of reviewers to be added to pull requests (GitHub user name)
+# reviewers:
+#  - egilmorez
+
+# A number of reviewers added to the pull request
+# Set 0 to add all the reviewers (default: 0)
+# numberOfReviewers: 0
+
+# A list of assignees, overrides reviewers if set
+assignees:
+  - egilmorez
+
+# A number of assignees to add to the pull request
+# Set to 0 to add all of the assignees.
+# Uses numberOfReviewers if unset.
+numberOfAssignees: 0
+
+# A list of keywords to be skipped the process that add reviewers if pull requests include it
+# skipKeywords:
+#   - wip

.github/workflows/assign-tech-writers.yml

@@ -0,0 +1,15 @@
+name: Assign tech writers
+
+on: 
+  pull_request: 
+    types: [labeled]
+jobs:
+  assign_tech_writers:
+    if: ${{github.event.label.name == 'doc-changes'}}
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: assign techwriters to PR
+        uses: kentaro-m/[email protected]
+        with:
+          configuration-path: ".github/auto_assign.yml"

.github/workflows/label-doc-changes.yml

@@ -0,0 +1,36 @@
+name: Label doc changes
+
+on: pull_request
+
+env:
+  GITHUB_PULL_REQUEST_HEAD_SHA: ${{ github.event.pull_request.head.sha }}
+  GITHUB_PULL_REQUEST_BASE_SHA: ${{ github.event.pull_request.base.sha }}
+
+jobs:
+  check_doc_changes:
+    name: Check if docs are being changed
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout Repo
+      uses: actions/checkout@master
+      with:
+        # This makes Actions fetch all Git history so check_changeset script can diff properly.
+        fetch-depth: 0
+    - name: Set up Node (14)
+      uses: actions/setup-node@v2
+      with:
+        node-version: 14.x
+    - name: Yarn install
+      run: yarn
+    - name: Run detect doc changes script
+      run: yarn ts-node-script scripts/exp/detect-doc-changes.ts
+      id: check-doc-changes
+    - name: Print if doc changed output
+      run: echo "${{steps.check-doc-changes.outputs.DOC_CHANGED}}"
+    - name: Add label if there are doc changes
+      uses: actions-ecosystem/[email protected]
+      if: ${{steps.check-doc-changes.outputs.DOC_CHANGED == 'true'}}
+      with:
+        labels: doc-changes
+        github_token: ${{ secrets.GITHUB_TOKEN }}

scripts/exp/detect-doc-changes.ts

@@ -0,0 +1,92 @@
+/**
+ * @license
+ * Copyright 2021 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import simpleGit from 'simple-git/promise';
+import { spawn } from 'child-process-promise';
+import * as tmp from 'tmp';
+
+/**
+ * check if there is any doc changes from baseSha to headSha
+ */
+async function docChanged(baseSha: string, headSha: string): Promise<boolean> {
+  const tmpDir = tmp.dirSync().name;
+  console.log('tmpDir is', tmpDir);
+  // clone repo to the tmpDir
+  await spawn(
+    'git',
+    ['clone', 'https://github.com/firebase/firebase-js-sdk.git', tmpDir],
+    { stdio: 'inherit' }
+  );
+
+  const git = simpleGit(tmpDir);
+
+  // generate reference docs using the baseSha
+  await git.checkout(baseSha);
+  await spawn('yarn', [], { cwd: tmpDir, stdio: 'inherit' });
+  await spawn('yarn', ['docgen:exp', 'devsite'], {
+    cwd: tmpDir,
+    stdio: 'inherit'
+  });
+
+  // revert yarn.lock, so we can checkout the headSha without conflict.
+  await git.checkout('yarn.lock');
+  // stash changes, so we can checkout the headSha without conflict.
+  await git.stash();
+
+  // generate reference docs using the headSha
+  await git.checkout(headSha);
+  await spawn('yarn', [], { cwd: tmpDir, stdio: 'inherit' });
+
+  // stage the docs generated by baseSha, so we can use git diff to tell if any docs are different in the headSha
+  await git.stash(['pop']);
+  await git.add('*');
+  await spawn('yarn', ['docgen:exp', 'devsite'], {
+    cwd: tmpDir,
+    stdio: 'inherit'
+  });
+
+  // check if any file is changed.
+  const diff = await git.diff();
+  // check if new files are created.
+  const untracked = await git.raw([
+    'ls-files',
+    '-o',
+    '--directory',
+    '--exclude-standard'
+  ]);
+
+  return !!diff || !!untracked;
+}
+
+// this function is supposed to run in the Github action.
+async function runInCI() {
+  const headSha = process.env.GITHUB_PULL_REQUEST_HEAD_SHA;
+  const mergeBaseSha = process.env.GITHUB_PULL_REQUEST_BASE_SHA;
+
+  if (!headSha || !mergeBaseSha) {
+    console.log('No merge base or head found. Is it not a PR?');
+    process.exit(1);
+  }
+
+  if (await docChanged(mergeBaseSha, headSha)) {
+    console.log(`::set-output name=DOC_CHANGED::true`);
+  } else {
+    console.log(`::set-output name=DOC_CHANGED::false`);
+  }
+}
+
+runInCI();

scripts/exp/remove-exp.js

@@ -32,7 +32,6 @@ const {
 // can be used in command line
 if (argv._[0]) {
   const dirOrFile = path.resolve(argv._[0]);
-
   try {
     accessSync(dirOrFile);
     if (statSync(dirOrFile).isFile()) {