Firebase 9.0.0-beta 6/7/8: Auth: INTERNAL ASSERTION FAILED: Expected a class definition

[arunmenon1975]

[REQUIRED] Describe your environment

• Operating System version: MacOS Big Sur(11.5.1)
• Browser version: Chrome 92.0.4515.131
• Firebase SDK version: Firebase 9.0.0-beta 6/Firebase 9.0.0-beta 7/Firebase 9.0.0-beta 8
• Firebase Product: Auth

[REQUIRED] Describe the problem

I am consistently getting the INTERNAL ASSERTION FAILED: Expected a class definition error and the app crashes while starting up. My app is simple and i really don't do anything else much (like calling APIs in the background etc).

I am using Firebase in a NextJS app and the SDKs are the beta versions(without compat). I have the emulators setup so development is local.

As far as i recall it was working fine in earlier beta versions though i cannot exactly remember the versions since it was a few weeks ago (in a POC app, maybe beta-4 or beta-5 perhaps)

Steps to reproduce:

Note: I am not sure if this can be reproduced in a clean install. I did not attempt it since the tested versions are explicitly beta and probably could be because of some known issues.

1. Install the beta versions mentioned in the issue
2. Setup emulators and initialise Firebase auth
3. Have a onAuthStateChanged early in the page loading process
4. attempt to load the page

The app crashed and i get the following error in the terminal:

WARNING: You are using the Auth Emulator, which is intended for local testing only.  Do not use with production credentials.
[2021-08-15T09:11:11.680Z]  @firebase/auth-exp: Auth (9.0.0-beta.6): INTERNAL ASSERTION FAILED: Expected a class definition
/Users/arunmenon/Sites/pwa/next/intl/sivadas/node_modules/@firebase/auth/dist/node/enum_maps-3878f8c6.js:295
    throw new Error(message);
          ^

Error: INTERNAL ASSERTION FAILED: Expected a class definition
    at debugFail (/Users/arunmenon/Sites/pwa/next/intl/sivadas/node_modules/@firebase/auth/dist/node/enum_maps-3878f8c6.js:295:11)
    at debugAssert (/Users/arunmenon/Sites/pwa/next/intl/sivadas/node_modules/@firebase/auth/dist/node/enum_maps-3878f8c6.js:306:9)
    at _getInstance (/Users/arunmenon/Sites/pwa/next/intl/sivadas/node_modules/@firebase/auth/dist/node/enum_maps-3878f8c6.js:328:5)
    at AuthImpl.<anonymous> (/Users/arunmenon/Sites/pwa/next/intl/sivadas/node_modules/@firebase/auth/dist/node/enum_maps-3878f8c6.js:2517:90)
    at step (/Users/arunmenon/Sites/pwa/next/intl/sivadas/node_modules/tslib/tslib.js:143:27)
    at Object.next (/Users/arunmenon/Sites/pwa/next/intl/sivadas/node_modules/tslib/tslib.js:124:57)
    at /Users/arunmenon/Sites/pwa/next/intl/sivadas/node_modules/tslib/tslib.js:117:75
    at new Promise (<anonymous>)
    at Object.__awaiter (/Users/arunmenon/Sites/pwa/next/intl/sivadas/node_modules/tslib/tslib.js:113:16)
    at /Users/arunmenon/Sites/pwa/next/intl/sivadas/node_modules/@firebase/auth/dist/node/enum_maps-3878f8c6.js:2514:54

Relevant Code:

How i initilaize:

import firebaseClientApp,{ initializeApp,FirebaseApp, getApp } from 'firebase/app';
// import { initializePerformance } from 'firebase/performance';
import { getFirestore, /* connectFirestoreEmulator, */  useFirestoreEmulator, FirebaseFirestore,} from 'firebase/firestore';
import {  browserLocalPersistence, getAuth, setPersistence, /* connectAuthEmulator, */ useAuthEmulator, Auth,indexedDBLocalPersistence} from 'firebase/auth';
import {getStorage, StorageService, /* connectStorageEmulator */ useStorageEmulator} from 'firebase/storage';

import { getAnalytics,Analytics } from "firebase/analytics";

const CLIENT_CONFIG = { 
    apiKey: process.env.NEXT_PUBLIC_FIREBASE_API_KEY,
    authDomain: process.env.NEXT_PUBLIC_FIREBASE_AUTH_DOMAIN,
    databaseURL: process.env.NEXT_PUBLIC_FIREBASE_DATABASE_URL,
    projectId: process.env.NEXT_PUBLIC_FIREBASE_PROJECT_ID,
    storageBucket: process.env.NEXT_PUBLIC_FIREBASE_STORAGE_BUCKET,
    messagingSenderId: process.env.NEXT_PUBLIC_FIREBASE_MESSAGING_SENDER_ID,
    appId: process.env.NEXT_PUBLIC_FIREBASE_APP_ID,
    measurementId: process.env.NEXT_PUBLIC_FIREBASE_MEASUREMENT_ID
 };


let firebaseApp: FirebaseApp;
let firestoreClient:FirebaseFirestore,authClient:Auth,storageClient:StorageService, analyticsClient: Analytics;

(() => {
  try {
     firebaseApp = getApp();
     try {
      analyticsClient = getAnalytics();
       
     } catch (error) {
       console.log(error)
     }
  } catch (error) {
    firebaseApp = initializeApp(CLIENT_CONFIG);
    //I kept getting the window not defined error so had to use this:
    if(typeof window !== "undefined"){
    analyticsClient = getAnalytics();
    }
    firestoreClient=getFirestore();
  // connectFirestoreEmulator(firestoreClient, 'localhost', 8080);
  useFirestoreEmulator(firestoreClient, 'localhost', 8080);
    try {
      authClient=getAuth();
      setPersistence(authClient, browserLocalPersistence);
      // connectAuthEmulator(authClient, "http://localhost:9099");
      useAuthEmulator(authClient, "http://localhost:9099");
  
      
    } catch (error) {
      console.error(error)
    }
     storageClient = getStorage();
    useStorageEmulator(storageClient, "localhost", 9199);
  //  connectStorageEmulator(storageClient,"localhost",9199);

  }
})()

export  {
  firebaseApp,
   firestoreClient,

    authClient,
    storageClient,
    analyticsClient
}

The initiation happens early in a React useEffect:

useEffect(() => {
      let unsub: Unsubscribe;
      const unsubscribe = onAuthStateChanged(authClient, (user) => {
        if(user){
          const {email, displayName, photoURL, providerId, providerData, uid, metadata, emailVerified} = user;
          logEvent(analyticsClient, 'login');
          //...more code, basically some firestore calls
          },(err=>{
            console.error("ERROR IN users snapshot", err)
          }));
        }
        else {
          dispatch({"kinds": Kinds.SetUserState, "payload": null})
        }
      });
      return () => {
        unsubscribe();
        if(unsub){
          unsub();
        }
      };
    }, []);

[sam-gc]

Hi @arunmenon1975, thanks for the issue and the detailed snippets. Is this failing when building in Node? browserLocalPersistence is not available in Node environments (that variable would be undefined), which would cause the issue with setPersistence(authClient, browserLocalPersistence);

I'd suggest wrapping that line in an environment check to make sure it only runs in the browser

[arunmenon1975]

Thanks for the response. It was a sort of show-stopper for me as i had just started out on some auth-related functionalities.

Is this failing when building in Node?

Yes, since I am using NextJs.

Since i am, at the moment, at a very early stage in the development of the app i did have the option to attempt a clean install of all the deps without risk of issues. I did that and included the latest beta, which currently is firebase@9.0.0-beta.7. I also wrapped all the module initialisations in an environment check(not just Auth).

Result: The error no longer appears and the build goes through fine.

So my guess is that primarily the issue got resolved with the addition of the environment check and probably even having a fresh copy of all the deps may have helped. Somehow the original code i had did work in earlier beta versions(pre 6) however.

This is good news for me since i thought i may have to stay back at an earlier version all through development and miss out on any new features, optimisations and bug fixes.

Thanks for the suggestions. I think ill close the issue since it is resolved.