Firebase Ionic - Returning Error - firebase

Question

I have a condition where I am checking if username is taken or not. If not, then I check if email is registered or not (if not, then proceed with account creation). I am separating firebase functions from business logic...but I am unable to figure out how to return error from createUserWithEmailAndPassword() to page class to handle further.
if(usernameTaken) {
}else{
/*Username is available - Check email taken or not (if not, register)*/
var error = self.firebaseProvider.registerUser(self.email,self.password,self.username, self.name);
if(error.code !== ""){
if(error.code == "auth/email-already-in-use"){
let alert = self.alertCtrl.create({
title: 'Email Exists',
subTitle: 'The email you entered is already registered.',
buttons: ['Retry']
});
alert.present();
}else if(error.code == 'auth/weak-password') {
let alert = self.alertCtrl.create({
title: 'Validation Error',
subTitle: 'The password entered is weak and should be 6 characters.',
buttons: ['Retry']
});
alert.present();
}
}
}
And here is the code in firebase.ts:
registerUser(email: string, password: string, username: string, name: string): (any) {
var self = this;
this.fbAuth.auth.createUserWithEmailAndPassword(email, password).then(function() {
var user = firebase.auth().currentUser;
self.createUserRecord(username, email, name);
}).catch(function(error) {
//Handle error
return error;
});
}
The returned error is null (undefined) hence nothing is working as expected. Please help.

Answer 1

Your code needs a bit of refactoring, your parent call is expecting a promise so var error is going to by a thenable object, it's not going to have a response of err.code.
Also returning an error in your registerUser class as a successful response can be difficult to debug so it's best to made the catch handle on the parent call.
if (usernameTaken) {
} else
/*Username is available - Check email taken or not (if not, register)*/
self.firebaseProvider.registerUser(self.email,self.password,self.username, self.name)
.then(resp => {
// Do Something
})
.catch(err => {
if (error.code !== "") {
if(error.code == "auth/email-already-in-use"){
let alert = self.alertCtrl.create({
title: 'Email Exists',
subTitle: 'The email you entered is already registered.',
buttons: ['Retry']
});
alert.present();
} else if(error.code == 'auth/weak-password') {
let alert = self.alertCtrl.create({
title: 'Validation Error',
subTitle: 'The password entered is weak and should be 6 characters.',
buttons: ['Retry']
});
alert.present();
}
}
});
}
You need to add a return in front of the this.fbAuth.auth.createUserWithEmailAndPassword call.
registerUser(email: string, password: string, username: string, name: string): Promise<any> {
var self = this;
return this.fbAuth.auth.createUserWithEmailAndPassword(email, password)
.then(function() {
var user = firebase.auth().currentUser;
return self.createUserRecord(username, email, name);
});
}
Now if the function throws an error it's handled in the parent class and you can see the difference between createUserRecord and an error.