How to solve FirebaseError: Expected first argument to collection() to be a CollectionReference, a DocumentReference or FirebaseFirestore problem?

Question

I am trying to set up Firebase with next.js. I am getting this error in the console.

FirebaseError: Expected first argument to collection() to be a CollectionReference, a DocumentReference or FirebaseFirestore

This is one of my custom hook

import { onAuthStateChanged, User } from '@firebase/auth'
import { doc, onSnapshot, Unsubscribe } from 'firebase/firestore'
import { useEffect, useState } from 'react'
import { auth, fireStore } from './firebase'

export const useUserData = () => {
  const [username, setUsername] = useState<string | null>(null)

  const [currentUser, setCurrentUser] = useState<User | null>(null)

  useEffect(() => {
    let unsubscribe: void | Unsubscribe

    onAuthStateChanged(auth, (user) => {
      if (user) {
        setCurrentUser(user)
        // The Problem is inside this try blog
        try {
          // the onsnapshot function is causing the problem
          console.log('firestore: ', fireStore)
          unsubscribe = onSnapshot(doc(fireStore, 'users', user.uid), (doc) => {
            setUsername(doc.data()?.username)
          })
        } catch (e) {
          console.log(e.message)
        }
      } else {
        setCurrentUser(null)
        setUsername(null)
      }
    })

    return unsubscribe
  }, [currentUser])

  return { currentUser, username }
}

I also have this firebase.ts file where I initialized my firebase app

import { FirebaseApp, getApps, initializeApp } from 'firebase/app'
import { getAuth } from 'firebase/auth'
import { getFirestore } from 'firebase/firestore/lite'
import { getStorage } from 'firebase/storage'

const firebaseConfig = {
  apiKey: 'some-api',
  authDomain: 'some-auth-domain',
  projectId: 'some-project-id',
  storageBucket: 'some-storage-bucket',
  messagingSenderId: 'some-id',
  appId: 'some-app-id',
  measurementId: 'some-measurement-id',
}

let firebaseApp: FirebaseApp

if (!getApps.length) {
  firebaseApp = initializeApp(firebaseConfig)
}

const fireStore = getFirestore(firebaseApp)
const auth = getAuth(firebaseApp)
const storage = getStorage(firebaseApp)

export { fireStore, auth, storage }

I don't know whether the problem is in the project initialization. I am pretty sure the error is generated from my custom hook file. I also found out that there must be something wrong with onSnapshot function. Am I passing the docRef wrong or something? What am I doing wrong here?

The console.log(firestore) log:

    type: "firestore-lite"
    _app: FirebaseAppImpl
    _automaticDataCollectionEnabled: false
    _config: {name: "[DEFAULT]", automaticDataCollectionEnabled: false}
    _container: ComponentContainer {name: "[DEFAULT]", providers: Map(15)}
    _isDeleted: false
    _name: "[DEFAULT]"
    _options:
    apiKey: 'some-api'
    authDomain: 'some-auth-domain'
    projectId: 'some-project-id'
    storageBucket: 'some-storage-bucket'
    messagingSenderId: 'some-id'
    appId: 'some-app-id'
    measurementId: 'some-measurement-id'
    [[Prototype]]: Object
    automaticDataCollectionEnabled: (...)
    config: (...)
    container: (...)
    isDeleted: (...)
    name: (...)
    options: (...)
    [[Prototype]]: Object
    _credentials: Q {auth: AuthInterop}
    _databaseId: H {projectId: "next-firebase-fireship", database: "(default)"}
    _persistenceKey: "(lite)"
    _settings: ee {host: "firestore.googleapis.com", ssl: true, credentials: undefined, ignoreUndefinedProperties: false, cacheSizeBytes: 41943040, …}
    _settingsFrozen: false
    app: (...)
    _initialized: (...)
    _terminated: (...)

Answer 1

Using getFirestore from lite library will not work with onSnapshot. You are importing getFirestore from lite version:

import { getFirestore } from 'firebase/firestore/lite'

Change the import to:

import { getFirestore } from 'firebase/firestore'

From the documentation,

The onSnapshot method and DocumentChange, SnapshotListenerOptions, SnapshotMetadata, SnapshotOptions and Unsubscribe objects are not included in lite version.

---

Another reason for this error to show up could be passing invalid first argument to collection() or doc() functions. They both take a Firestore instance as first argument.

// Ensure that "db" is defined and initialized
const db = getFirestore();
// console.log(db);

const colRef = collection(db, "collection_name");