how to use firebase in react native code example

Example 1: add firebase in react

import * as firebase from 'firebase'

const firebaseConfig = {
    apiKey: "AIzaSyC6EDL8gMkZc3GGzGveMqWe5zvAr5DNiL4",
    authDomain: "blood-components.firebaseapp.com",
    databaseURL: "https://blood-components.firebaseio.com",
    projectId: "blood-components",
    storageBucket: "blood-components.appspot.com",
    messagingSenderId: "388223113819",
    appId: "1:388223113819:web:1273570a12add0fedafd7e",
    measurementId: "G-K6NM078FWD"
};

// Initialize Firebase
firebase.initializeApp(firebaseConfig);
const auth = firebase.auth();
const db = firebase.firestore();

//initiating references to the databases
const usersRef = db.collection('users')

// for privileges purposes
const functions = firebase.functions();

//google provider sign-in
const googleProvider = new firebase.auth.GoogleAuthProvider();


export { firebase, db, auth, functions, googleProvider }

Example 2: react native firebase

// Using npm
npm install --save @react-native-firebase/app

# create your firebase android project and follow the steps for implementations. 
# check: https://rnfirebase.io/#generating-android-credentials

Example 3: react native firebase

/* Answer to: "react native firebase" */

/*
  React Native Firebase is the officially recommended collection
  of packages that brings React Native support for all Firebase
  services on both Android and iOS apps.
*/