Skip to main content

A month of Flutter: Sign in with Google


Originally published on bendyworks.com.

Building on the work configuring Firebase Auth for Android and iOS, it's time to go get a user's details. This will be leveraging the already installed google_sign_in and firebase_auth packages.
The big change is the addition of the Auth class.
class Auth {
  Auth({
    @required this.googleSignIn,
    @required this.firebaseAuth,
  });

  final GoogleSignIn googleSignIn;
  final FirebaseAuth firebaseAuth;

  Future<FirebaseUser> signInWithGoogle() async {
    final GoogleSignInAccount googleAccount = await googleSignIn.signIn();
    // TODO(abraham): Handle null googleAccount
    final GoogleSignInAuthentication googleAuth =
        await googleAccount.authentication;
    return firebaseAuth.signInWithGoogle(
      accessToken: googleAuth.accessToken,
      idToken: googleAuth.idToken,
    );
  }
}
This class gets passed a FirebaseAuth instance and a GoogleSignIninstance for interactions with the external authentication services. On GoogleSignIn the signIn method will trigger a user account selection prompt. When the user confirms their account selection a GoogleSignInAccount instance will be returned. On GoogleSignInAccount I'll call authentication to get the current user's tokens. Finally I'll exchange the GoogleSignInAuthentication for a FirebaseUser with signInWithGoogle.
I added a TODO to improve error handling so it doesn't get forgotten.
The app now has an authenticated FirebaseUser with all the accompanying details.
I'll now update SignInFab to leverage the new Auth service and print out the user's displayName in the Flutter logs.
void _handleSignIn() {
  auth
      .signInWithGoogle()
      .then((FirebaseUser user) => print('Hi ${user.displayName}'));
}
I/flutter (29142): Hi Birb Dev
SignInFab will also need to be passed an Auth instance in _MyHomePageState.
SignInFab(
  auth: Auth(
    firebaseAuth: FirebaseAuth.instance,
    googleSignIn: GoogleSignIn(),
  ),
)
This is what the account selector looks like on Android:

iOS prompts to allow access to google.com:

Most of the new code is actually tests and mocking the external Google and Firebase APIs. It's complected and deserves it's own article so come back tomorrow to learn more.

Code changes

Comments

Popular posts from this blog

Installing Storytlr the lifestreaming platform

" Storytlr  is an open source lifestreaming and micro blogging platform. You can use it for a single user or it can act as a host for many people all from the same installation." I've been looking for something like Storytlr for a few months now or at least trying to do it with Drupal . While I love Drupal and FeedAPI  I did not want to spend all that time building a lifestream website. So I've been playing around with Storytlr instead and found it very easy. Here is how I got it up and running on a Ubuntu EC2 server. You can also check out the official Storytlr install instructions . Assumptions: LAMP stack installed and running. Domain setup for a directory. MySQL database and user ready to go. Lets get started! Get the code : wget http://storytlr.googlecode.com/files/storytlr-0.9.2.tgz tar -xvzf storytlr-0.9.2.tgz You can find out the  latest stable release  on Storytlr's downloads page. Import the database : Within protected/install is database.sq

Google+ could bring world peace

Google is the largest web application on the planet with over one billion unique visiters each month. This means that one in seven people on the entire planet used Google over the last 30 days. Having such a massive user base means that someone from pretty much every single geographical, political, and religious group is a user of Google. Once Google+  hits a billion our pals from Mountain View will be in the unique position of potentially bringing about world peace. And I don't mean bringing FarmVille to Google+. How so, you might ask? Well Google is collecting so much personal information that they can create incredibly accurate profiles of personal beliefs and comfort zones. With these personas, the 900,000 machines , a few algorithms, and some time Google can connect people one follow at a time that are of similar interests but ever so slightly contrarian. Eventually even the most conservative views will become more open and accepting just through the everyday contact. On

Sync is currently experiencing problems

Update : I now recommend you install Google Chrome  and  disable  the built in Browser as it supports encrypting all synced data. After picking up a gorgeous  Galaxy Nexus yesterday I was running into an issue where my browser data wasn't syncing to the phone. After a little Googling I found this is commonly caused by having all of my synced Chrome data encrypted instead of the default of only encrypting the passwords. These are the steps I went through to get my dat syncing again without losing any of it. The exact error I was getting was "Sync is currently experiencing problems. It will be back shortly." In Google Chrome open the personal stuff settings page by clicking this link or by opening the wrench menu, and click on "signed in with example@gmail.com".  Hit "disconnect your Google Account" to temporarily disable syncing from your browser. Visit the Google Dashboard and "Stop sync and delete data from Google". I waite