@firebase/app-compat

What is @firebase/app-compat?

The @firebase/app-compat package is a compatibility layer for Firebase that allows developers to use the Firebase SDK with an API surface that is compatible with the older 'firebase' npm package (version 8 and below). It enables developers to upgrade to the modular Firebase SDK (version 9 and above) without having to refactor all of their existing code that was written using the older syntax.

What are @firebase/app-compat's main functionalities?

Initialization

This code initializes a Firebase app instance using the older, non-modular syntax. It is used to set up the Firebase context for further interactions with Firebase services.

const firebase = require('@firebase/app-compat');
const app = firebase.initializeApp({ apiKey: 'API_KEY', authDomain: 'PROJECT_ID.firebaseapp.com', projectId: 'PROJECT_ID' });

Authentication

This code demonstrates how to sign in a user with an email and password using Firebase Authentication. It uses the older syntax for ease of use with existing codebases.

const firebase = require('@firebase/app-compat');
const auth = firebase.auth();
auth.signInWithEmailAndPassword('[e-mail]', 'password').then((userCredential) => {
  // Handle successful authentication
}).catch((error) => {
  // Handle errors
});

Realtime Database

This code snippet shows how to listen for real-time updates from the Firebase Realtime Database at a specific path. It uses the traditional Firebase syntax.

const firebase = require('@firebase/app-compat');
const database = firebase.database();
database.ref('path/to/data').on('value', (snapshot) => {
  const data = snapshot.val();
  // Use the data
});

Firestore

This code sample demonstrates how to retrieve a document from a Firestore collection using the older Firebase syntax. It is useful for developers who have existing Firestore interactions written in the non-modular style.

const firebase = require('@firebase/app-compat');
const firestore = firebase.firestore();
firestore.collection('users').doc('user_id').get().then((doc) => {
  if (doc.exists) {
    const user = doc.data();
    // Use the user data
  }
}).catch((error) => {
  // Handle errors
});

Other packages similar to @firebase/app-compat

firebase

The 'firebase' package is the traditional, non-modular SDK for Firebase. It provides a similar API surface to @firebase/app-compat but is designed for use with Firebase SDK versions 8 and below. Developers using this package would not have access to the tree-shaking and modular features of the newer Firebase SDK.

react-firebase-hooks

The 'react-firebase-hooks' package provides a set of reusable React hooks for Firebase. It simplifies the process of connecting a React application to Firebase services. While it offers a different approach by leveraging React's hooks, it provides similar functionalities for authentication, database, and firestore interactions.

@angular/fire

The '@angular/fire' package is the official library for Firebase and Angular integration. It provides services and utilities to connect Angular applications with Firebase features. Like @firebase/app-compat, it abstracts Firebase interactions but is specifically tailored for Angular applications.

README

@firebase/app-compat

This is the compatibility layer for the Firebase App package, which recreates the v8 API.

This package is not intended for direct usage, and should only be used via the officially supported firebase package.