Firebase admin integration

Goal

Perform admin actions with Firebase admin like read all users or update data.

Firebase Admin installation

Obtain your service account private key and store it in a json file https://firebase.google.com/docs/admin/setup

npm install firebase-admin --save

Init Firebase

Run this block of code below before all the others

// global 1
async function initFirebase() {
  const admin = require('firebase-admin');
  const serviceAccount = require('./appid-firebase-adminsdk.json');
  admin.initializeApp({
    credential: admin.credential.cert(serviceAccount)
  });
  const auth = admin.auth();
  const db = admin.firestore();
  return {auth, db};
}

const {auth, db} = await initFirebase();

Show all users

Paginate the results present in auth More details here: https://firebase.google.com/docs/auth/web/start?hl=en

//exec: /usr/local/bin/node
async function getUserEmails(auth, nextPageToken) {
    const listUsersResult = await auth.listUsers(1000, nextPageToken);
    listUsersResult.users.map(user => {
        //if (new Date(user.metadata.creationTime) > new Date("2022-12-20T00:00:00")) {
        console.log(user.email);
        //}
    });
    if (listUsersResult.pageToken) {
        await getUserEmails(auth, listUsersResult.pageToken);
    }
}

await getUserEmails(auth);

Read Firestore

Use a hierarchy such as /UserID/DocumentID More details here: https://firebase.google.com/docs/firestore/query-data/get-data?hl=en

Firebase admin only works for NodeJs app (not browser)

//exec: /usr/local/bin/node
const user = await auth.getUserByEmail(email);
console.log(user);
const docsRef = db.collection(user.uid);
const snapshot = await docsRef.get();
// show nbr of objects for user
console.log("Usage: " + snapshot.size);
// show all documents for user
snapshot.forEach(doc => {
    console.log(doc.id, '=>', doc.data());
});

Write Firestore

//exec: /usr/local/bin/node
const user = await auth.getUserByEmail(email);
let collectionRef = db.collection("profile/");
let documentRef = collectionRef.doc(user.uid);

// Delete a document
//documentRef.delete().then(() => {
//    console.log('Document successfully deleted.');
//});

// Update a document
documentRef.set({ name: "John Doe"}).then(() => {
    return documentRef.get();
}).then(documentSnapshot => {
    let field = documentSnapshot.get('name');
    console.log(`Retrieved field value: ${field}`);
});