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javascriptfirebasefirebase-realtime-databasefirebase-admin

Firebase web modular API - initializeApp()

I am switching over to the JavaScript web modular API from JavaScript namespaced (compat). My code is a Firebase Function with a http trigger running on GCP, so the code 'lives' in the GCP infra. My thought is that, because of this, I do not need to specify a bunch of data to initialise the App and Database, which would be the case if my code ran on ReactJS, or any other front end framework.

In my old code I simply initialised the app in a file called firebase-db that was included wherever needed. This also gave me a handle to the database. The database handle is no longer needed with the modular API.

// This is the old namespaced code
const admin = require("firebase-admin");

const app = admin.initializeApp();
const database = admin.database(app);
module.exports = database;

In my new code I do not have this file and I am simply using the below code in my files.

const { ref, getDatabase, get } = require("firebase/database");
...

However, this does not work. I get an error that clearly states that the 'App' need to be initialised.

FirebaseError: Firebase: No Firebase App '[DEFAULT]' has been created - call initializeApp() first (app/no-app)

My new firebase-db file looks like this; but it does not work:

// This is the new modular code
const { initializeApp } = require("firebase-admin");
const { getDatabase } = require("firebase/database");

const app = initializeApp(); //<-- This line generates an error!
const database = getDatabase(app);

module.exports = database;

The call initializeApp(); generates error:

TypeError: Cannot read property 'INTERNAL' of undefined

I have tied to look into the documentation, but cannot find any good examples on how to initialise the App so that I can get the Dabase handle using getDatabase().

https://firebase.google.com/docs/database/admin/retrieve-data#node.js_19 https://firebase.google.com/docs/database/web/read-and-write#web-modular-api_5 https://firebase.google.com/docs/reference/js/database.md#equalto_51c2c8b

Any help much appreciated! /K

Solution

  • The Firebase web SDKs aren't replacements for firebase-admin. On the backend, you still have to use firebase-admin and its normal API. There is no "modular" API for firebase-admin.

    To be more specific:

    • "firebase/database" is designed for frontend web applications. It's not really designed for use on the backend (except possibly in very specific situations, which probably don't apply to you). Documentation containing both classic and modular APIs: https://firebase.google.com/docs/database/web/start
    • "firebase-admin" is still the main package for using with nodejs backends. It's not obsolete, its API hasn't changed significantly, and it provides no modular API that mirrors what you find in the modern web SDKs. Documentation: https://firebase.google.com/docs/database/admin/start