WIP: Scale lambda

.github/workflows/lambda-scale-runners.yml

@@ -0,0 +1,26 @@
+name: Lambda Scale Runners
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    paths:
+      - .github/workflows/lambda-scale-runners.yml
+      - "modules/runners/lambdas/scale-runners/**"
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    container: node:12
+    defaults:
+      run:
+        working-directory: modules/runners/lambdas/scale-runners
+
+    steps:
+      - uses: actions/checkout@v2
+      - name: Install dependencies
+        run: yarn install
+      - name: Run tests
+        run: yarn test
+      - name: Build distribution
+        run: yarn build

modules/runners/lambdas/scale-runners/package.json

@@ -23,5 +23,8 @@
     "ts-node-dev": "^1.0.0-pre.44",
     "typescript": "^3.8.3"
   },
-  "dependencies": {}
+  "dependencies": {
+    "@octokit/auth-app": "^2.4.5",
+    "@octokit/rest": "^17.6.0"
+  }
 }

modules/runners/lambdas/scale-runners/src/lambda.ts

@@ -1,8 +1,11 @@
 import { handle } from './scale-runners/handler';
 
 module.exports.handler = async (event: any, context: any, callback: any) => {
-  const statusCode = await handle(event.headers, event.body);
-  return callback(null, {
-    statusCode: statusCode,
-  });
+  try {
+    await handle(event.eventSource, JSON.parse(event.body));
+    return callback(null);
+  } catch (e) {
+    console.error(e);
+    return callback('Failed handling SQS event');
+  }
 };

modules/runners/lambdas/scale-runners/src/scale-runners/handler.test.ts

@@ -0,0 +1,47 @@
+import { ActionRequestMessage, handle } from './handler';
+
+import { createAppAuth } from '@octokit/auth-app';
+import { Octokit } from '@octokit/rest';
+
+jest.mock('@octokit/auth-app', () => ({
+  createAppAuth: jest.fn().mockImplementation(() => jest.fn().mockImplementation(() => ({ token: 'Blaat' }))),
+}));
+const mockOctokit = { checks: { get: jest.fn() }, actions: { listRepoWorkflowRuns: jest.fn() } };
+jest.mock('@octokit/rest', () => ({
+  Octokit: jest.fn().mockImplementation(() => mockOctokit),
+}));
+
+const TEST_DATA: ActionRequestMessage = {
+  id: 1,
+  eventType: 'check_run',
+  repositoryName: 'hello-world',
+  repositoryOwner: 'Codertocat',
+  installationId: 2,
+};
+
+describe('handler', () => {
+  beforeEach(() => {
+    process.env.GITHUB_APP_KEY = 'TEST_CERTIFICATE_DATA';
+    process.env.GITHUB_APP_ID = '1337';
+    process.env.GITHUB_APP_CLIENT_ID = 'TEST_CLIENT_ID';
+    process.env.GITHUB_APP_CLIENT_SECRET = 'TEST_CLIENT_SECRET';
+    jest.clearAllMocks();
+    mockOctokit.actions.listRepoWorkflowRuns.mockImplementation(() => ({
+      total_count: 1,
+    }));
+  });
+
+  it('ignores non-sqs events', async () => {
+    expect.assertions(1);
+    expect(handle('aws:s3', TEST_DATA)).rejects.toEqual(Error('Cannot handle non-SQS events!'));
+  });
+
+  it('checks queued workflows', async () => {
+    await handle('aws:sqs', TEST_DATA);
+    expect(mockOctokit.actions.listRepoWorkflowRuns).toBeCalledWith({
+      owner: TEST_DATA.repositoryOwner,
+      repo: TEST_DATA.repositoryName,
+      status: 'queued',
+    });
+  });
+});

modules/runners/lambdas/scale-runners/src/scale-runners/handler.ts

@@ -1,5 +1,48 @@
-import { IncomingHttpHeaders } from 'http';
+import { createAppAuth } from '@octokit/auth-app';
+import { Octokit } from '@octokit/rest';
 
-export const handle = async (headers: IncomingHttpHeaders, payload: any): Promise<number> => {
-  return 200;
+export interface ActionRequestMessage {
+  id: number;
+  eventType: string;
+  repositoryName: string;
+  repositoryOwner: string;
+  installationId: number;
+}
+
+async function createGithubClient(installationId: number): Promise<Octokit> {
+  const privateKey = process.env.GITHUB_APP_KEY as string;
+  const appId: number = parseInt(process.env.GITHUB_APP_ID as string);
+  const clientId = process.env.GITHUB_APP_CLIENT_ID as string;
+  const clientSecret = process.env.GITHUB_APP_CLIENT_SECRET as string;
+
+  try {
+    const auth = createAppAuth({
+      id: appId,
+      privateKey: privateKey,
+      installationId: installationId,
+      clientId: clientId,
+      clientSecret: clientSecret,
+    });
+    const installationAuthentication = await auth({ type: 'installation' });
+
+    return new Octokit({
+      auth: installationAuthentication.token,
+    });
+  } catch (e) {
+    Promise.reject(e);
+  }
+}
+
+export const handle = async (eventSource: string, payload: ActionRequestMessage): Promise<void> => {
+  if (eventSource !== 'aws:sqs') throw Error('Cannot handle non-SQS events!');
+  const githubClient = await createGithubClient(payload.installationId);
+  const queuedWorkflows = await githubClient.actions.listRepoWorkflowRuns({
+    owner: payload.repositoryOwner,
+    repo: payload.repositoryName,
+    // @ts-ignore (typing is incorrect)
+    status: 'queued',
+  });
+  console.info(
+    `Repo ${payload.repositoryOwner}/${payload.repositoryName} has ${queuedWorkflows.total_count} queued workflow runs`,
+  );
 };