Automatically generate dependabot changesets

Signed-off-by: Johan Haals <johan.haals@gmail.com>
2022-01-07 16:34:05 +01:00
parent 3cf9ff0ba4
commit 6dfb8eb848
2 changed files with 119 additions and 0 deletions
@@ -0,0 +1,20 @@
+name: "Dependabot changeset maker"
+on:
+- pull_request_target
+
+jobs:
+  generate-changeset:
+    runs-on: ubuntu-latest
+    if: ${{ github.actor == 'dependabot[bot]' }}
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v2
+      with:
+        fetch-depth: 2
+        ref: ${{ github.head_ref }} 
+    - name: Configure Git
+      run: |
+        git config --global user.email noreply@backstage.io
+        git config --global user.name 'Github changeset workflow'
+    - name: Generate changesets
+      run: node scripts/dependabot-changeset-maker.js
@@ -0,0 +1,99 @@
+#!/usr/bin/env node
+/*
+ * Copyright 2022 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+const { promises: fs } = require('fs');
+const { execFile: execFileCb } = require('child_process');
+const { promisify } = require('util');
+
+const execFile = promisify(execFileCb);
+
+// Parses package.json files and returns the package names
+async function getPackagesNames(files) {
+  const names = [];
+  for (const file of files) {
+    const data = JSON.parse(await fs.readFile(file, 'utf8'));
+    names.push(data.name);
+  }
+  return names;
+}
+
+async function createChangeset(fileName, commitMessage, packages) {
+  const pkgs = packages.map(pkg => `'${pkg}': patch`).join('\n');
+  const message = commitMessage.replace(/(b|B)ump ([a-z-]+)/, 'Bump `$2`');
+  const body = `---\n${pkgs}\n---\n\n${message}`;
+  await fs.writeFile(fileName, body);
+}
+
+async function runPlain(cmd, ...args) {
+  try {
+    const { stdout } = await execFile(cmd, args, { shell: true });
+    return stdout.trim();
+  } catch (error) {
+    if (error.stderr) {
+      process.stderr.write(error.stderr);
+    }
+    if (!error.code) {
+      throw error;
+    }
+    throw new Error(
+      `Command '${[cmd, ...args].join(' ')}' failed with code ${error.code}`,
+    );
+  }
+}
+
+async function main() {
+  const branch = await runPlain('git', 'branch', '--show-current');
+  if (!branch.startsWith('dependabot/')) {
+    console.log('Not a dependabot branch');
+    return;
+  }
+
+  const diffFiles = await runPlain('git', 'diff', '--name-only', 'HEAD~1');
+  if (diffFiles.includes('.changeset')) {
+    console.log('Changeset already exists');
+    return;
+  }
+  const files = diffFiles
+    .split('\n')
+    .filter(file => file !== 'package.json') // skip root package.json
+    .filter(file => file.includes('package.json'));
+
+  if (!files.length) {
+    console.log('no package.json changes, skipping');
+    return;
+  }
+
+  const packageNames = await getPackagesNames(files);
+  const shortHash = await runPlain('git', 'rev-parse', '--short', 'HEAD');
+  const fileName = `.changeset/dependabot-${shortHash.trim()}.md`;
+  const commitMessage = await runPlain(
+    'git',
+    'show',
+    '--pretty=format:%s',
+    '-s',
+    'HEAD',
+  );
+  await createChangeset(fileName, commitMessage, packageNames);
+  await runPlain('git', 'add', fileName);
+  await runPlain('git', 'commit', '-C', 'HEAD', '--amend', '--no-edit');
+  await runPlain('git', 'push', '--force');
+}
+
+main().catch(error => {
+  console.error(error.stack);
+  process.exit(1);
+});