Different set of authentications for different apps in the same firebase project - firebase

I am building a booking system and I am using firebase as the backend. The system has two parts:
the customer end which is an app.
the business end which is a website.
I am using the same firestore database for both and also using the same Firebase Authentication project.
So I need two sets of authentication sets one for the customer end and another for the business end.
I have added two apps in a firebase project for sharing the database. My issue is the users shouldn't be able to sign in at the business web app with their credentials and vise versa.
How can I create two sets of authentication details one for each app?

Authenticating a user with Firebase does not determine whether the user has access to anything app-specific. Authentication is merely a method where the user proves who they are.
You then use this information about the user to determine what they can do in your app(s), a process that is known as authorization. Authentication and authorization go hand in hand, but are still separate steps. And Firebase Authentication only takes care of the authentication part. Authorization is up to your app.
The typical approach to your scenario is to actually have only one set of credentials for each user. If the same user needs access to both the app, and the web site, they can sign in with the same credentials. Based on your knowledge of the user, you then grant or deny them access.
Most apps have a users collection with a user profile document for each user (using their UID as the key). Then after the user is authenticated your app could read the user's profile document and read for example two fields named isCustomer and isBusiness, to determine if the user has access to the app/site. You'd also use those fields in the security rules of your database to grant/deny access.
An alternative is to give each user profile in Firebase Authentication a custom claim to determine whether they are a customer and/or a business. In that case you'd need server-side code to set the custom isCustomer and/or isBusiness claims and use this in your code (and database) to grant or deny access.
Also see:
How to create firebase admin user for authentication in java
How to use the same Firebase Auth for Two different Flutter apps?
role based authorization and role based access control flutter

Related

Firebase Firestore integrate chat using existing backend for user data

I develop an iOS application and I'm using Node & Postgres for handling user data and authentication. I would like to add a chat feature to my app and I chose Firestore for this.
My question is how should I link the existing user data with a Firebase collection of users without re-implementing the authentication part from the ground up. Right now the authentication is based on JWTs with access and refresh tokens.
In order to link my existing users, I can add the userId already present in my database to the users collection that I will create in Firestore, but I need some kind of authentication to ensure security.
While the token for Firebase is also a JWT, it will probably have to be separate from your existing JWT, as it contains Firebase-specific information (such as the project ID), and they're signed with different keys.
After you authenticate the user with your own backend, mint a custom token for Firebase authentication with the information you want to use in Firebase/Firestore and security rules, pass that to the client, and sign them in to Firebase with it.

Firebase Authentication with popup - allow only registered user

I wanted to create website where I have separate Sign In and Sign Up form. I also want to have Google authentication with Firebase.
I've implemented it like this both on sign in and sign up page:
await FIREBASE_AUTH.signInWithPopup(googleAuthProvider);
But this code will always create new user.
What I would like to do is to block creating new user on sign in page, only log them in if user already exists (e.g. as I require terms of use consent on sign up page, but I don't want to require it on sign up page - it would be quite weird)
There is no way in Firebase Authentication to prevent users from signing up, while still allowing them to sign in if they're already created. The reason for this is that Firebase Authentication merely focuses on allowing users to authenticate themselves, so to prove who they are by providing credentials. What they can then do in your app is known as authorization, and is up to you to implement in your front-end application code, back-end application code, and server-side security rules.
For example, if you use one of Firebase's databases (Cloud Firestore or Realtime Database), you'll typically maintain a list of approved user's in that list (either their email or their UID). Then before granting the user access to specific screens in your app or data in your database, you check if the users exists in that list. If not, you don't grant access to the screen or data.
I don't see an issue here, when a user uses google auth when they already have an account it will create a new account with their in some cases new data he might have changed in his google account.
In case your users hold other data in your database I'm pretty sure there's a google auth API for that issue.

How to login to Firebase from an ERP system?

I would like to login to Firebase from an ERP system.
i.e. once logged into the ERP system, that login can be used to access a Firestore db.
The Firebase docs describe a common case: "Add an additional identifier on a user".
Is it possible to use this common case to login to Firebase from the ERP system?
Control Access with Custom Claims and Security Rules
User roles can be defined for the following common cases:
Add an additional identifier on a user. For example, a Firebase user could map to a different UID in another system.
If you want to use the users from an existing authentication system to authenticate against Firebase, you'll need to implement a custom authentication provider.
With such a provider, you:
Sign the user in with your existing system in a trusted environment (e.g. on a server).
You then use the user's credentials to mint a custom JWT token.
Send that token back the client, which then finally
Uses the custom token to sign in to Firebase.
At this point, the user is signed in to Firebase Authentication in the client, and their UID (and other properties from their token) are available in the Firestore security rules.

Where does firebase save it's simple login users?

I am currently using firebase to make an ionic app. I am using firebase simple login for social auth (facebook, twitter, email & password). The auth works perfectly, it $broadcasts the authed user. However it doesn't seem to create a user in the actual firebase db. I was wondering how I can get the users that have been authed using my app.
For most of the authentication protocols it supports, Firebase doesn't store user data anywhere. Even for the protocols where it does store data (I only know of email+password doing this), it stores this information in a place that your application can't access (though you can find those users in the dashboard of your Firebase).
To quote the Firebase documentation:
It does not store profile or user state in your Firebase. To persist user data you must save it to your Firebase.
What most applications end up doing, is keeping a list of users inside their Firebase that they manage themselves. So when a user first authenticates with the application, it creates a node under /users/<uid> that contains the information for that user.
See this section of the Firebase documentation that describes storing user data.
Firebase does not store profile or user state in your Firebase instance. To persist user data you must save it to your Firebase.
Firebase provides multiple authentications services
Using existing social login providers such Facebook, Twitter, Google, and GitHub. Using these services provides an option for your users to access your application without creating a new account.
Using built-in support for logging in with email & password. This requires registration and account creation that is handled by Firebase. The user account information is stored outside you application.
Using a custom authentication to implement existing server-side authentication, single sign-on, legacy systems, or third-party OAuth based services (such as Yahoo).
Once authenticated, Firebase return a variable auth to your application that you can use for authorization and access control. This variable is null for unauthenticated users, but for authenticated users it is an object containing the user's unique (auth.uid) and potentially other data about the user.
If you want to persist additional user information such as name
and location, then you need to use auth.uid and store it in your
Firebase with additional profile data.
Internally, Firebase generates JSON Web Tokens (JWTs) and creates authenticated sessions by calling Firebase.loginWithCustomToken() with those tokens. Each user is assigned a uid (a unique ID), which is guaranteed to be distinct across all providers, and to never change for a specific authenticated user.
The user data for firebase authentication is stored in firebaseLocalStorageDb in IndexedDB. After login to website, if you delete firebaseLocalStorageDb, the login user data for firebase authentication is all deleted so you need to log in website again.

How do I restrict signup to a product in Firebase

If I create a new product, use simple auth, there is a "create user" API. How do I restrict it so that only invited emails (either by the email or via a one-time key) can sign up? Doesn't seem to fit easily into the rules, but I am probably missing something.
First, I should point out that the core Firebase API uses JSON Web Tokens for auth, which you can generate yourself, so you have full control over the creation of user accounts and can restrict it however you like:
https://www.firebase.com/docs/security/custom-login.html
I'm guessing you're referring to our Simple Login service.
Simple Login is a service that provides some common login options. It has no way to restrict creation of new accounts. However, you can restrict what those accounts can do with Firebase. For example, you could set your security rules up so that only user accounts in some authorized list (in Firebase) are actually able to read or write data.

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