displayName not set when creating new email account

[ambrice]

I have the following function for updating firebase database user entry when a new user is created:

exports.addUserData = functions.auth.user().onCreate((user) => {
    console.log("Adding new user " + user.uid);
    return admin.auth().getUser(user.uid).then(userRecord => {
        var userData = admin.database().ref('/users').child(user.uid);
        userData.child('name').set(userRecord.displayName);
        userData.child('email').set(userRecord.email);
        userData.child('is_admin').set(false);
        admin.database().ref('/users_idx').child(md5(userRecord.email)).set(userData.key);
    });
});

When creating a new email account from the firebase-ui web library, this function triggers correctly. When using firebase-ui android library 4.2.1, the userRecord.displayName is undefined even though a full name was entered.

[samtstern]

For FirebaseUI android this is expected behavior. Behind the scenes we do two operations:

1. Create user with email/password
2. Immediately update the display name

It's operation (1) that triggers the cloud function, since that's when the user is created. What I don't understand is how firebaseui-web is getting around this issue. @bojeil-google any idea?

[ambrice]

That was originally an issue, but I worked around that in the function by calling getUser() instead of using the user that was passed into the trigger. I don't know why that works when the user is created from the web library but not the android library.

[samtstern]

@ambrice in that case it's just a race condition. If your getUser request happens before we update the display name, then you will not see a name in your cloud function. It's possible that FirebaseUI on the web is just faster, but that's not behavior you should rely on.

Since there's nothing I can do here to make this work every time, I am going to close the issue. I know it sounds like a terrible solution but you could try adding a ~5second delay within your function before fetching the user record to make the race condition less likely.