feat: introduce CommitSigner interface (#442)

* feat: introduce CommitSigner interface

* chore: fix lint

* ignore eslint config

* address review

.eslintrc.json

@@ -1,3 +1,4 @@
 {
-  "extends": "./node_modules/gts"
+  "extends": "./node_modules/gts",
+  "root": true
 }

owlbot.py

@@ -20,5 +20,6 @@
     '.github/release-please.yml',
     'renovate.json',
     '.eslintignore',
+    '.eslintrc.json',
     '.prettierignore',
 ])

src/github/commit-and-push.ts

@@ -21,7 +21,7 @@ import {
 } from '../types';
 import {Octokit} from '@octokit/rest';
 import {logger} from '../logger';
-import {createCommit} from './create-commit';
+import {createCommit, CreateCommitOptions} from './create-commit';
 import {CommitError} from '../errors';
 
 const DEFAULT_FILES_PER_COMMIT = 100;
@@ -142,6 +142,10 @@ export async function updateRef(
   }
 }
 
+interface CommitAndPushOptions extends CreateCommitOptions {
+  filesPerCommit?: number;
+}
+
 /**
  * Given a set of changes, apply the commit(s) on top of the given branch's head and upload it to GitHub
  * Rejects if GitHub V3 API fails with the GitHub error response
@@ -162,8 +166,9 @@ export async function commitAndPush(
   originBranch: BranchDomain,
   commitMessage: string,
   force: boolean,
-  filesPerCommit: number = DEFAULT_FILES_PER_COMMIT
+  options?: CommitAndPushOptions
 ) {
+  const filesPerCommit = options?.filesPerCommit ?? DEFAULT_FILES_PER_COMMIT;
   const tree = generateTreeObjects(changes);
   for (const treeGroup of inGroupsOf(tree, filesPerCommit)) {
     const treeSha = await createTree(octokit, originBranch, refHead, treeGroup);
@@ -172,7 +177,8 @@ export async function commitAndPush(
       originBranch,
       refHead,
       treeSha,
-      commitMessage
+      commitMessage,
+      options
     );
   }
   await updateRef(octokit, originBranch, refHead, force);

src/github/create-commit.ts

@@ -13,10 +13,16 @@
 // limitations under the License.
 
 import {Octokit} from '@octokit/rest';
-import {RepoDomain} from '../types';
+import {RepoDomain, CommitSigner, UserData} from '../types';
 import {logger} from '../logger';
 import {CommitError} from '../errors';
 
+export interface CreateCommitOptions {
+  signer?: CommitSigner;
+  author?: UserData;
+  committer?: UserData;
+}
+
 /**
  * Create a commit with a repo snapshot SHA on top of the reference HEAD
  * and resolves with the SHA of the commit.
@@ -27,15 +33,26 @@ import {CommitError} from '../errors';
  * @param {string} treeSha the tree SHA that this commit will point to
  * @param {string} message the message of the new commit
  * @returns {Promise<string>} the new commit SHA
+ * @see https://docs.github.com/en/rest/git/commits?apiVersion=2022-11-28#create-a-commit
  */
 export async function createCommit(
   octokit: Octokit,
   origin: RepoDomain,
   refHead: string,
   treeSha: string,
-  message: string
+  message: string,
+  options: CreateCommitOptions = {}
 ): Promise<string> {
   try {
+    const signature = options.signer
+      ? await options.signer.generateSignature({
+          message,
+          tree: treeSha,
+          parents: [refHead],
+          author: options.author,
+          committer: options.committer,
+        })
+      : undefined;
     const {
       data: {sha, url},
     } = await octokit.git.createCommit({
@@ -44,6 +61,9 @@ export async function createCommit(
       message,
       tree: treeSha,
       parents: [refHead],
+      signature,
+      author: options.author,
+      committer: options.committer,
     });
     logger.info(`Successfully created commit. See commit at ${url}`);
     return sha;

src/index.ts

@@ -22,7 +22,7 @@ import {
   FileDiffContent,
   CreateReviewCommentUserOptions,
 } from './types';
-export {Changes} from './types';
+export {Changes, CommitData, CommitSigner} from './types';
 import {Octokit} from '@octokit/rest';
 import {logger, setupLogger} from './logger';
 import {
@@ -192,7 +192,7 @@ async function createPullRequest(
     originBranch,
     gitHubConfigs.message,
     gitHubConfigs.force,
-    gitHubConfigs.filesPerCommit
+    options
   );
 
   const description: Description = {

src/types.ts

@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+import {CreateCommitOptions} from './github/create-commit';
+
 export type FileMode = '100644' | '100755' | '040000' | '160000' | '120000';
 
 /**
@@ -72,7 +74,7 @@ export interface Description {
 /**
  * The user options for creating GitHub PRs
  */
-export interface CreatePullRequestUserOptions {
+export interface CreatePullRequestUserOptions extends CreateCommitOptions {
   // the owner of the target fork repository
   upstreamOwner: string;
   // the name of the target fork repository
@@ -200,3 +202,20 @@ export interface Logger {
   debug: LogFn;
   trace: LogFn;
 }
+
+export interface UserData {
+  name: string;
+  email: string;
+}
+
+export interface CommitData {
+  message: string;
+  tree: string;
+  parents: string[];
+  author?: UserData;
+  committer?: UserData;
+}
+
+export interface CommitSigner {
+  generateSignature(commit: CommitData): Promise<string>;
+}

test/commit-and-push.ts

@@ -21,7 +21,14 @@ import * as sinon from 'sinon';
 import {GetResponseTypeFromEndpointMethod} from '@octokit/types';
 import * as handler from '../src/github/commit-and-push';
 import * as createCommitModule from '../src/github/create-commit';
-import {Changes, FileData, TreeObject, RepoDomain} from '../src/types';
+import {
+  Changes,
+  FileData,
+  TreeObject,
+  RepoDomain,
+  CommitData,
+  CommitSigner,
+} from '../src/types';
 import {createCommit} from '../src/github/create-commit';
 import {CommitError} from '../src/errors';
 
@@ -37,6 +44,17 @@ type CreateCommitResponse = GetResponseTypeFromEndpointMethod<
   typeof octokit.git.createCommit
 >;
 
+class FakeCommitSigner implements CommitSigner {
+  signature: string;
+  constructor(signature: string) {
+    this.signature = signature;
+  }
+  /* eslint-disable @typescript-eslint/no-unused-vars */
+  async generateSignature(_commit: CommitData): Promise<string> {
+    return this.signature;
+  }
+}
+
 before(() => {
   setup();
 });
@@ -199,7 +217,7 @@ describe('Commit', () => {
     // tests
     const sha = await createCommit(octokit, origin, head, treeSha, message);
     assert.strictEqual(sha, createCommitResponse.data.sha);
-    sandbox.assert.calledOnceWithExactly(stubCreateCommit, {
+    sandbox.assert.calledOnceWithMatch(stubCreateCommit, {
       owner: origin.owner,
       repo: origin.repo,
       message,
@@ -324,12 +342,85 @@ describe('Commit and push function', async () => {
       ],
       base_tree: getCommitResponse.data.tree.sha,
     });
-    sandbox.assert.calledOnceWithExactly(stubCreateCommit, {
+    sandbox.assert.calledOnceWithMatch(stubCreateCommit, {
+      owner: origin.owner,
+      repo: origin.repo,
+      message,
+      tree: createTreeResponse.data.sha,
+      parents: [oldHeadSha],
+    });
+    sandbox.assert.calledOnceWithExactly(stubUpdateRef, {
+      owner: origin.owner,
+      repo: origin.repo,
+      sha: createCommitResponse.data.sha,
+      ref: 'heads/test-branch-name',
+      force: true,
+    });
+  });
+  it('allows configuring a commit signer', async () => {
+    changes.set('foo.txt', {
+      mode: '100755',
+      content: 'some file content',
+    });
+    // setup
+    const stubGetCommit = sandbox
+      .stub(octokit.git, 'getCommit')
+      .resolves(getCommitResponse);
+    const stubCreateTree = sandbox
+      .stub(octokit.git, 'createTree')
+      .resolves(createTreeResponse);
+    const stubCreateCommit = sandbox
+      .stub(octokit.git, 'createCommit')
+      .resolves(createCommitResponse);
+    const stubUpdateRef = sandbox.stub(octokit.git, 'updateRef');
+    const fakeSigner = new FakeCommitSigner('fake-signature');
+    const options = {
+      author: {
+        name: 'Test Committer',
+        email: '[email protected]',
+      },
+      signer: fakeSigner,
+    };
+    const signatureSpy = sandbox.spy(fakeSigner, 'generateSignature');
+    // tests
+    await handler.commitAndPush(
+      octokit,
+      oldHeadSha,
+      changes,
+      {branch: branchName, ...origin},
+      message,
+      true,
+      options
+    );
+    sandbox.assert.calledOnceWithExactly(stubGetCommit, {
+      owner: origin.owner,
+      repo: origin.repo,
+      commit_sha: oldHeadSha,
+    });
+    sandbox.assert.calledWithExactly(stubCreateTree, {
+      owner: origin.owner,
+      repo: origin.repo,
+      tree: [
+        {
+          path: 'foo.txt',
+          mode: '100755',
+          type: 'blob',
+          content: 'some file content',
+        },
+      ],
+      base_tree: getCommitResponse.data.tree.sha,
+    });
+    sandbox.assert.calledOnceWithMatch(stubCreateCommit, {
       owner: origin.owner,
       repo: origin.repo,
       message,
       tree: createTreeResponse.data.sha,
       parents: [oldHeadSha],
+      signature: 'fake-signature',
+      author: {
+        name: 'Test Committer',
+        email: '[email protected]',
+      },
     });
     sandbox.assert.calledOnceWithExactly(stubUpdateRef, {
       owner: origin.owner,
@@ -338,6 +429,15 @@ describe('Commit and push function', async () => {
       ref: 'heads/test-branch-name',
       force: true,
     });
+    sandbox.assert.calledOnceWithMatch(signatureSpy, {
+      message,
+      tree: createTreeResponse.data.sha,
+      parents: [oldHeadSha],
+      author: {
+        name: 'Test Committer',
+        email: '[email protected]',
+      },
+    });
   });
   it('Forwards GitHub error if getCommit fails', async () => {
     const error = new Error('Error committing');
@@ -396,7 +496,7 @@ describe('Commit and push function', async () => {
       {branch: branchName, ...origin},
       message,
       true,
-      6
+      {filesPerCommit: 6}
     );
 
     sinon.assert.calledTwice(createTreeStub);