Add a unit test for the action entry point

__fixtures__/events/default.json

@@ -0,0 +1,21 @@
+{
+  "inputs": {
+    "jobID": "1",
+    "jobToken": "xxx",
+    "credentialsToken": "yyy",
+    "dependabotAPIURL": "http://localhost:9000"
+  },
+  "ref": "main",
+  "repository": {
+    "owner": {
+      "login": "dependabot"
+    },
+    "name": "dependabot-core"
+  },
+  "sender": {
+    "type": "User"
+  },
+  "installation": null,
+  "organization": null,
+  "workflow": "--workflow-yaml-goes-here--"
+}

__tests__/helpers.ts

@@ -25,7 +25,7 @@ export const removeDanglingUpdaterContainers = async (): Promise<void> => {
   await docker.pruneContainers()
 }
 
-export const runFakeDependabotApi = async (port: number): Promise<Function> => {
+export const runFakeDependabotApi = async (port = 9000): Promise<Function> => {
   const server = spawn('node', [
     `${path.join(__dirname, 'server/server.js')}`,
     `${port}`
@@ -44,3 +44,13 @@ export const runFakeDependabotApi = async (port: number): Promise<Function> => {
     server.kill()
   }
 }
+
+export const eventFixturePath = (fixtureName: string): string => {
+  return path.join(
+    __dirname,
+    '..',
+    '__fixtures__',
+    'events',
+    `${fixtureName}.json`
+  )
+}

__tests__/main.test.ts

@@ -1,2 +1,156 @@
-// shows how the runner will run a javascript action with env / stdout protocol
-test('test runs', () => {})
+import * as core from '@actions/core'
+import {Context} from '@actions/github/lib/context'
+import {APIClient} from '../src/api-client'
+import {Updater} from '../src/updater'
+import * as inputs from '../src/inputs'
+import {run} from '../src/main'
+
+import {eventFixturePath} from './helpers'
+
+// We do not need to build actual containers or run updates for this test.
+jest.mock('../src/api-client')
+jest.mock('../src/image-service')
+jest.mock('../src/updater')
+
+describe('run', () => {
+  let context: Context
+
+  beforeEach(async () => {
+    jest.spyOn(core, 'info').mockImplementation(jest.fn())
+    jest.spyOn(core, 'setFailed').mockImplementation(jest.fn())
+  })
+
+  afterEach(async () => {
+    jest.clearAllMocks() // Reset any mocked classes
+  })
+
+  describe('when the run follows the happy path', () => {
+    beforeAll(() => {
+      process.env.GITHUB_EVENT_PATH = eventFixturePath('default')
+      process.env.GITHUB_EVENT_NAME = 'workflow_dispatch'
+      context = new Context()
+    })
+
+    test('it signs off at completion without any errors', async () => {
+      await run(context)
+
+      expect(core.setFailed).not.toHaveBeenCalled()
+      expect(core.info).toHaveBeenCalledWith(
+        expect.stringContaining('🤖 ~fin~')
+      )
+    })
+  })
+
+  describe('when the action is triggered on an unsupported event', () => {
+    beforeAll(() => {
+      process.env.GITHUB_EVENT_PATH = eventFixturePath('default')
+      process.env.GITHUB_EVENT_NAME = 'issue_created'
+      context = new Context()
+    })
+
+    test('it explains the event is unsupported without logging to dependabot-api', async () => {
+      await run(context)
+
+      expect(core.setFailed).not.toHaveBeenCalled()
+      expect(core.info).toHaveBeenCalledWith(
+        expect.stringContaining(
+          "Dependabot Updater Action does not support 'issue_created' events."
+        )
+      )
+    })
+  })
+
+  describe('when there is an error retrieving job parameters', () => {
+    beforeEach(() => {
+      jest.spyOn(inputs, 'getJobParameters').mockImplementationOnce(
+        jest.fn(() => {
+          throw new Error('unexpected error retrieving job params')
+        })
+      )
+
+      process.env.GITHUB_EVENT_PATH = eventFixturePath('default')
+      process.env.GITHUB_EVENT_NAME = 'workflow_dispatch'
+      context = new Context()
+    })
+
+    test('it relays an error to dependabot-api and marks the job as processed', async () => {
+      await run(context)
+
+      expect(core.setFailed).toHaveBeenCalledWith(
+        expect.stringContaining('unexpected error retrieving job params')
+      )
+    })
+  })
+
+  describe('when there is an error retrieving job details from DependabotAPI', () => {
+    beforeEach(() => {
+      jest
+        .spyOn(APIClient.prototype, 'getJobDetails')
+        .mockImplementationOnce(
+          jest.fn(async () =>
+            Promise.reject(new Error('error getting job details'))
+          )
+        )
+
+      process.env.GITHUB_EVENT_PATH = eventFixturePath('default')
+      process.env.GITHUB_EVENT_NAME = 'workflow_dispatch'
+      context = new Context()
+    })
+
+    test('it relays an error to dependabot-api and marks the job as processed', async () => {
+      await run(context)
+
+      expect(core.setFailed).toHaveBeenCalledWith(
+        expect.stringContaining('error getting job details')
+      )
+    })
+  })
+
+  describe('when there is an error retrieving job credentials from DependabotAPI', () => {
+    beforeEach(() => {
+      jest
+        .spyOn(APIClient.prototype, 'getCredentials')
+        .mockImplementationOnce(
+          jest.fn(async () =>
+            Promise.reject(new Error('error getting credentials'))
+          )
+        )
+
+      process.env.GITHUB_EVENT_PATH = eventFixturePath('default')
+      process.env.GITHUB_EVENT_NAME = 'workflow_dispatch'
+      context = new Context()
+    })
+
+    test('it relays an error to dependabot-api and marks the job as processed', async () => {
+      await run(context)
+
+      expect(core.setFailed).toHaveBeenCalledWith(
+        expect.stringContaining('error getting credentials')
+      )
+    })
+  })
+
+  describe('when there is an error running the update', () => {
+    beforeAll(() => {
+      jest
+        .spyOn(Updater.prototype, 'runUpdater')
+        .mockImplementationOnce(
+          jest.fn(async () =>
+            Promise.reject(new Error('error running the update'))
+          )
+        )
+
+      process.env.GITHUB_EVENT_PATH = eventFixturePath('default')
+      process.env.GITHUB_EVENT_NAME = 'workflow_dispatch'
+      context = new Context()
+    })
+
+    test('it relays an error to dependabot-api and marks the job as processed', async () => {
+      await run(context)
+
+      expect(core.setFailed).toHaveBeenCalledWith(
+        expect.stringContaining('error running the update')
+      )
+    })
+  })
+})

src/main.ts

@@ -1,5 +1,6 @@
 import * as core from '@actions/core'
 import * as github from '@actions/github'
+import {Context} from '@actions/github/lib/context'
 import {getJobParameters} from './inputs'
 import {ImageService} from './image-service'
 import {Updater} from './updater'
@@ -11,15 +12,15 @@ export const UPDATER_IMAGE_NAME =
 export const PROXY_IMAGE_NAME =
   'docker.pkg.github.com/github/dependabot-update-job-proxy:latest'
 
-async function run(): Promise<void> {
+export async function run(context: Context): Promise<void> {
   try {
     // Decode JobParameters:
-    const params = getJobParameters(github.context)
+    const params = getJobParameters(context)
     if (params === null) {
       return // No parameters, nothing to do
     }
 
-    core.info(JSON.stringify(params))
+    core.debug(JSON.stringify(params))
 
     core.setSecret(params.jobToken)
     core.setSecret(params.credentialsToken)
@@ -39,9 +40,10 @@ async function run(): Promise<void> {
     await ImageService.pull(PROXY_IMAGE_NAME)
 
     await updater.runUpdater()
+    core.info('🤖 ~fin~')
   } catch (error) {
-    core.setFailed(error.message)
+    core.setFailed(error)
   }
 }
 
-run()
+run(github.context)