Update simple HTTP testing to explain emulator interactions

[samtstern]

See:
firebase/firebase-tools#3098 (comment)

[markgoho]

@samtstern maybe you could help me out here -- I've accomplished setting up http testing:

const { expect } = require('chai');
const axios = require('axios');
const qs = require('qs');
const admin = require('firebase-admin');
const test = require('firebase-functions-test')({
  projectId: process.env.GCLOUD_PROJECT,
});

const axiosConfig = (functionName, data) => {
  return {
    method: 'post',
    url: `http://localhost:5001/${process.env.GCLOUD_PROJECT}/us-central1/${functionName}`,
    headers: {
      'Content-Type': 'application/x-www-form-urlencoded',
    },
    data,
  };
};

describe('Unit tests', () => {
  after(() => {
    test.cleanup();
  });

  it('tests a new deployment', async () => {
    const data = qs.stringify({
      payload:
        '{"status": "started", "branch": "feature-fix", "env": "hotfix-2", "app": "enroll", "user_name": "kvootla", "org": "maine", "repo": "enroll", "commit_sha": "abc1234" }',
    });

    const config = axiosConfig('branchDeployment', data);

    let responsePayload;
    try {
      // Make the http request
      responsePayload = await axios(config);
    } catch (e) {
      console.log('ERROR:', e);
    }

    // Wait for the promise to be resolved and then check the sent text
    expect(responsePayload.data).to.deep.eq({
      status: 'started',
      branch: 'feature-fix',
      env: 'hotfix-2',
      app: 'enroll',
      user_name: 'kvootla',
      org: 'maine',
      repo: 'enroll',
      commit_sha: 'abc1234',
    });
  }).timeout(5000);
});

This works when run with firebase emulators:exec --project=fakeproject \"npm run test\"

However, as soon as I also try to check that a value was set in Firestore, e.g. adding this just below the payload assertion:

const envSnap = await admin
      .firestore()
      .collection('orgs')
      .doc('maine')
      .collection('environments')
      .doc('hotfix-2')
      .get();

    expect(envSnap.data()).to.eql({
      status: 'started',
      branch: 'feature-fix',
      env: 'hotfix-2',
      app: 'enroll',
      user_name: 'kvootla',
      org: 'maine',
      repo: 'enroll',
      commit_sha: 'abc1234',
    });

I get the following error:

 Error: The default Firebase app does not exist. Make sure you call initializeApp() before using any of the Firebase services.
      at FirebaseAppError.FirebaseError [as constructor] (node_modules\firebase-admin\lib\utils\error.js:44:28)
      at FirebaseAppError.PrefixedFirebaseError [as constructor] (node_modules\firebase-admin\lib\utils\error.js:90:28)
      at new FirebaseAppError (node_modules\firebase-admin\lib\utils\error.js:125:28)
      at FirebaseNamespaceInternals.app (node_modules\firebase-admin\lib\firebase-namespace.js:101:19)
      at FirebaseNamespace.app (node_modules\firebase-admin\lib\firebase-namespace.js:430:30)
      at FirebaseNamespace.ensureApp (node_modules\firebase-admin\lib\firebase-namespace.js:444:24)
      at FirebaseNamespace.fn (node_modules\firebase-admin\lib\firebase-namespace.js:304:30)
      at Context.<anonymous> (test\functions.spec.js:54:8)
      at processTicksAndRejections (internal/process/task_queues.js:97:5)

[samtstern]

@markgoho that error message is correct, you have not called admin.initializeApp() anywhere so you can't use admin.firestore() to perform actions.

Also make sure you have FIRESTORE_EMULATOR_HOST set correctly in your environment or the Admin SDK will attempt to talk to prod. If you're running your tests through firebase emulators:exec this is handled for you.

[markgoho]

thank you so much @samtstern that did solve this issue!

does your functions.spec.js file in this repo get the intializeApp() call from https://github.com/firebase/quickstart-testing/blob/master/unit-test-cloud-functions/functions/test/functions.spec.js#L15 where you require the index.js file?

it seems like I'll need two separate spec files:

• one where I'm manually calling initializeApp because I'm not importing my functions index
• one where I'm importing my functions index and letting it call initializeApp

[samtstern]

@markgoho that's a great point and I hadn't thought about it! Yes we're somewhat accidentally inheriting the app initialization from the wrapped functions themselves since they're running inside the same process rather than being accessed over the network.