Add auto-merge feature for GitHub and GitLab

bin/cml/pr.js

@@ -19,6 +19,11 @@ exports.builder = (yargs) =>
         type: 'boolean',
         description: 'Output in markdown format [](url).'
       },
+      autoMerge: {
+        type: 'boolean',
+        description:
+          'Mark the PR/MR for automatic merging after tests pass (unsupported by Bitbucket).'
+      },
       remote: {
         type: 'string',
         default: GIT_REMOTE,

bin/cml/pr.test.js

@@ -15,6 +15,8 @@ describe('CML e2e', () => {
         --log         Maximum log level
                 [string] [choices: \\"error\\", \\"warn\\", \\"info\\", \\"debug\\"] [default: \\"info\\"]
         --md          Output in markdown format [](url).                     [boolean]
+        --auto-merge  Mark the PR/MR for automatic merging after tests pass
+                      (unsupported by Bitbucket).                            [boolean]
         --remote      Sets git remote.                    [string] [default: \\"origin\\"]
         --user-email  Sets git user email.   [string] [default: \\"[email protected]\\"]
         --user-name   Sets git user name.            [string] [default: \\"Olivaw[bot]\\"]

package.json

@@ -70,10 +70,12 @@
     "@actions/github": "^4.0.0",
     "@npcz/magic": "^1.3.12",
     "@octokit/core": "^3.5.1",
+    "@octokit/graphql": "^4.8.0",
     "@octokit/plugin-throttling": "^3.5.2",
     "@octokit/rest": "18.0.0",
     "colors": "1.4.0",
     "ec2-spot-notification": "^2.0.3",
+    "exponential-backoff": "^3.1.0",
     "form-data": "^3.0.1",
     "fs-extra": "^9.1.0",
     "git-url-parse": "^11.6.0",

src/cml.js

@@ -340,7 +340,8 @@ class CML {
     const {
       remote = GIT_REMOTE,
       globs = ['dvc.lock', '.gitignore'],
-      md
+      md,
+      autoMerge
     } = opts;
 
     await this.ci(opts);
@@ -392,7 +393,11 @@ class CML {
       await exec(`git checkout -B ${target} ${sha}`);
       await exec(`git checkout -b ${source}`);
       await exec(`git add ${paths.join(' ')}`);
-      await exec(`git commit -m "CML PR for ${shaShort} [skip ci]"`);
+      let commitMessage = `CML PR for ${shaShort}`;
+      if (!autoMerge) {
+        commitMessage += ' [skip ci]';
+      }
+      await exec(`git commit -m "${commitMessage}"`);
       await exec(`git push --set-upstream ${remote} ${source}`);
     }
 
@@ -405,7 +410,8 @@ Automated commits for ${this.repo}/commit/${sha} created by CML.
       source,
       target,
       title,
-      description
+      description,
+      autoMerge
     });
 
     return renderPr(url);

src/drivers/bitbucket_cloud.js

@@ -108,7 +108,13 @@ class BitbucketCloud {
 
   async prCreate(opts = {}) {
     const { projectPath } = this;
-    const { source, target, title, description } = opts;
+    const { source, target, title, description, autoMerge } = opts;
+
+    if (autoMerge) {
+      throw new Error(
+        'Auto-merging is unsupported by Bitbucket Cloud. See https://jira.atlassian.com/browse/BCLOUD-14286'
+      );
+    }
 
     const body = JSON.stringify({
       title,

src/drivers/github.js

@@ -6,6 +6,7 @@ const fetch = require('node-fetch');
 
 const github = require('@actions/github');
 const { Octokit } = require('@octokit/rest');
+const { withCustomRequest } = require('@octokit/graphql');
 const { throttling } = require('@octokit/plugin-throttling');
 const tar = require('tar');
 const ProxyAgent = require('proxy-agent');
@@ -313,12 +314,18 @@ class Github {
   }
 
   async prCreate(opts = {}) {
-    const { source: head, target: base, title, description: body } = opts;
+    const {
+      source: head,
+      target: base,
+      title,
+      description: body,
+      autoMerge
+    } = opts;
     const { owner, repo } = ownerRepo({ uri: this.repo });
     const { pulls } = octokit(this.token, this.repo);
 
     const {
-      data: { html_url: htmlUrl }
+      data: { html_url: htmlUrl, node_id: nodeId }
     } = await pulls.create({
       owner,
       repo,
@@ -328,9 +335,81 @@ class Github {
       body
     });
 
+    if (autoMerge) {
+      await this.prAutoMerge({ pullRequestId: nodeId, base });
+    }
+
     return htmlUrl;
   }
 
+  /**
+   * @param {{ branch: string }} opts
+   * @returns {Promise<boolean>}
+   */
+  async isProtected({ branch }) {
+    const octo = octokit(this.token, this.repo);
+    const { owner, repo } = this.ownerRepo();
+    try {
+      await octo.repos.getBranchProtection({
+        branch,
+        owner,
+        repo
+      });
+      return true;
+    } catch (error) {
+      if (error.message === 'Branch not protected') {
+        return false;
+      }
+      throw error;
+    }
+  }
+
+  /**
+   * @param {{ pullRequestId: number, base: string }} param0
+   * @returns {Promise<void>}
+   */
+  async prAutoMerge({ pullRequestId, base }) {
+    const octo = octokit(this.token, this.repo);
+    const graphql = withCustomRequest(octo.request);
+
+    try {
+      await graphql(
+        `
+          mutation autoMerge($pullRequestId: ID!) {
+            enablePullRequestAutoMerge(
+              input: { pullRequestId: $pullRequestId }
+            ) {
+              clientMutationId
+            }
+          }
+        `,
+        {
+          pullRequestId
+        }
+      );
+    } catch (error) {
+      if (
+        error.message.includes("Can't enable auto-merge for this pull request")
+      ) {
+        const { owner, repo } = this.ownerRepo();
+        const settingsUrl = `https://github.com/${owner}/${repo}/settings`;
+
+        const isProtected = await this.isProtected({ branch: base });
+        if (!isProtected) {
+          throw new Error(
+            `Enabling Auto-Merge failed. Please set up branch protection and add "required status checks" for branch '${base}': ${settingsUrl}/branches`
+          );
+        }
+
+        throw new Error(
+          `Enabling Auto-Merge failed. Enable the feature in your repository settings: ${settingsUrl}#merge_types_auto_merge`
+        );
+      }
+
+      throw error;
+    }
+  }
+
   async prCommentCreate(opts = {}) {
     const { report: body, prNumber } = opts;
     const { owner, repo } = ownerRepo({ uri: this.repo });

src/drivers/gitlab.js

@@ -6,6 +6,7 @@ const fs = require('fs').promises;
 const fse = require('fs-extra');
 const { resolve } = require('path');
 const ProxyAgent = require('proxy-agent');
+const { backOff } = require('exponential-backoff');
 
 const { fetchUploadData, download, exec } = require('../utils');
 
@@ -235,7 +236,7 @@ class Gitlab {
 
   async prCreate(opts = {}) {
     const projectPath = await this.projectPath();
-    const { source, target, title, description } = opts;
+    const { source, target, title, description, autoMerge } = opts;
 
     const endpoint = `/projects/${projectPath}/merge_requests`;
     const body = new URLSearchParams();
@@ -244,15 +245,39 @@ class Gitlab {
     body.append('title', title);
     body.append('description', description);
 
-    const { web_url: url } = await this.request({
+    const { web_url: url, iid } = await this.request({
       endpoint,
       method: 'POST',
       body
     });
 
+    if (autoMerge) {
+      await this.prAutoMerge({ mergeRequestId: iid });
+    }
+
     return url;
   }
 
+  /**
+   * @param {{ mergeRequestId: string }} param0
+   * @returns {Promise<void>}
+   */
+  async prAutoMerge({ mergeRequestId }) {
+    const projectPath = await this.projectPath();
+
+    const endpoint = `/projects/${projectPath}/merge_requests/${mergeRequestId}/merge`;
+    const body = new URLSearchParams();
+    body.append('merge_when_pipeline_succeeds', true);
+
+    await backOff(() =>
+      this.request({
+        endpoint,
+        method: 'PUT',
+        body
+      })
+    );
+  }
+
   async prCommentCreate(opts = {}) {
     const projectPath = await this.projectPath();
     const { report, prNumber } = opts;

src/drivers/gitlab.test.js

@@ -40,11 +40,10 @@ describe('Non Enviromental tests', () => {
 
   test('Runner token', async () => {
     const output = await client.runnerToken();
-
-    expect(output.length).toBe(20);
+    expect(output.length >= 20).toBe(true);
   });
 
-  test.skip('updateGitConfig', async () => {
+  test('updateGitConfig', async () => {
     const client = new GitlabClient({
       repo: 'https://gitlab.com/test/test',
       token: 'dXNlcjpwYXNz'