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Authenticate with Firebase using Password-Based Accounts on Apple Platforms

You can use Firebase Authentication to let your users authenticate with Firebase using their email addresses and passwords, and to manage your app's password-based accounts.

Before you begin

Use Swift Package Manager to install and manage Firebase dependencies.

In Xcode, with your app project open, navigate to File > Add Packages.
When prompted, add the Firebase Apple platforms SDK repository:

  https://github.com/firebase/firebase-ios-sdk.git

Choose the Firebase Authentication library.
Add the -ObjC flag to the Other Linker Flags section of your target's build settings.
When finished, Xcode will automatically begin resolving and downloading your dependencies in the background.

Next, perform some configuration steps:

If you haven't yet connected your app to your Firebase project, do so from the Firebase console.
Enable Email/Password sign-in:
1. In the Firebase console, open the Auth section.
2. On the Sign in method tab, enable the Email/password sign-in method and click Save.

Create a password-based account

To create a new user account with a password, complete the following steps in your app's sign-in activity:

Import the FirebaseCore module in your UIApplicationDelegate, as well as any other Firebase modules your app delegate uses. For example, to use Cloud Firestore and Authentication:

SwiftUI

import SwiftUI
import FirebaseCore
import FirebaseFirestore
import FirebaseAuth
// ...

Swift

import FirebaseCore
import FirebaseFirestore
import FirebaseAuth
// ...

Objective-C

@import FirebaseCore;
@import FirebaseFirestore;
@import FirebaseAuth;
// ...

Configure a FirebaseApp shared instance in your app delegate's application(_:didFinishLaunchingWithOptions:) method:

SwiftUI

// Use Firebase library to configure APIs
FirebaseApp.configure()

Swift

// Use Firebase library to configure APIs
FirebaseApp.configure()

Objective-C

// Use Firebase library to configure APIs
[FIRApp configure];

If you're using SwiftUI, you must create an application delegate and attach it to your App struct via UIApplicationDelegateAdaptor or NSApplicationDelegateAdaptor. You must also disable app delegate swizzling. For more information, see the SwiftUI instructions.

SwiftUI

@main
struct YourApp: App {
  // register app delegate for Firebase setup
  @UIApplicationDelegateAdaptor(AppDelegate.self) var delegate

  var body: some Scene {
    WindowGroup {
      NavigationView {
        ContentView()
      }
    }
  }
}

When a new user signs up using your app's sign-up form, complete any new account validation steps that your app requires, such as verifying that the new account's password was correctly typed and meets your complexity requirements.

Create a new account by passing the new user's email address and password to createUser.

Swift

Auth.auth().createUser(withEmail: email, password: password) { authResult, error in
  // ...
}

Objective-C

[[FIRAuth auth] createUserWithEmail:email
                           password:password
                         completion:^(FIRAuthDataResult * _Nullable authResult,
                                      NSError * _Nullable error) {
  // ...
}];

If the new account was successfully created, the user is signed in, and you can get the user's account data from the result object that's passed to the callback method.

Sign in a user with an email address and password

The steps for signing in a user with a password are similar to the steps for creating a new account. In your app's sign-in activity, do the following:

Import the FirebaseCore module in your UIApplicationDelegate, as well as any other Firebase modules your app delegate uses. For example, to use Cloud Firestore and Authentication:

SwiftUI

import SwiftUI
import FirebaseCore
import FirebaseFirestore
import FirebaseAuth
// ...

Swift

import FirebaseCore
import FirebaseFirestore
import FirebaseAuth
// ...

Objective-C

@import FirebaseCore;
@import FirebaseFirestore;
@import FirebaseAuth;
// ...

Configure a FirebaseApp shared instance in your app delegate's application(_:didFinishLaunchingWithOptions:) method:

SwiftUI

// Use Firebase library to configure APIs
FirebaseApp.configure()

Swift

// Use Firebase library to configure APIs
FirebaseApp.configure()

Objective-C

// Use Firebase library to configure APIs
[FIRApp configure];

SwiftUI

@main
struct YourApp: App {
  // register app delegate for Firebase setup
  @UIApplicationDelegateAdaptor(AppDelegate.self) var delegate

  var body: some Scene {
    WindowGroup {
      NavigationView {
        ContentView()
      }
    }
  }
}

When a user signs in to your app, pass the user's email address and password to signIn.

Swift

Auth.auth().signIn(withEmail: email, password: password) { [weak self] authResult, error in
  guard let strongSelf = self else { return }
  // ...
}

Objective-C

[[FIRAuth auth] signInWithEmail:self->_emailField.text
                       password:self->_passwordField.text
                     completion:^(FIRAuthDataResult * _Nullable authResult,
                                  NSError * _Nullable error) {
  // ...
}];

If the user successfully signs in, you can get the user's account data from the result object that's passed to the callback method.

Recommended: Set a password policy

You can improve account security by enforcing password complexity requirements.

To configure a password policy for your project, open the Password policy tab on the Authentication Settings page of the Firebase console:

Authentication Settings

Firebase Authentication password policies support the following password requirements:

Lowercase character required
Uppercase character required
Numeric character required
Non-alphanumeric character required

The following characters satisfy the non-alphanumeric character requirement: ^ $ * . [ ] { } ( ) ? " ! @ # % & / \ , > < ' : ; | _ ~
Minimum password length (ranges from 6 to 30 characters; defaults to 6)
Maximum password length (maximum length of 4096 characters)

You can enable password policy enforcement in two modes:

Require: Attempts to sign up fail until the user updates to a password that complies with your policy.
Notify: Users are allowed to sign up with a non-compliant password. When using this mode, you should check if the user's password complies with the policy on the client side and prompt the user in some way to update their password if it does not comply.

New users are always required to choose a password that complies with your policy.

If you have active users, we recommend not enabling force upgrade on sign in unless you intend to block access to users whose passwords don't comply with your policy. Instead, use notify mode, which allows users to sign in with their current passwords, and inform them of the requirements their password lacks.

Recommended: Enable email enumeration protection

Some Firebase Authentication methods that take email addresses as parameters throw specific errors if the email address is unregistered when it must be registered (for example, when signing in with an email address and password), or registered when it must be unused (for example, when changing a user's email address). While this can be helpful for suggesting specific remedies to users, it can also be abused by malicious actors to discover the email addresses registered by your users.

To mitigate this risk, we recommend you enable email enumeration protection for your project using the Google Cloud gcloud tool. Note that enabling this feature changes Firebase Authentication's error reporting behavior: be sure your app doesn't rely on the more specific errors.

Next steps

After a user signs in for the first time, a new user account is created and linked to the credentials—that is, the user name and password, phone number, or auth provider information—the user signed in with. This new account is stored as part of your Firebase project, and can be used to identify a user across every app in your project, regardless of how the user signs in.

In your apps, you can get the user's basic profile information from the User object. See Manage Users.
In your Firebase Realtime Database and Cloud Storage Security Rules, you can get the signed-in user's unique user ID from the auth variable, and use it to control what data a user can access.

You can allow users to sign in to your app using multiple authentication providers by linking auth provider credentials to an existing user account.

To sign out a user, call signOut:.

Swift

let firebaseAuth = Auth.auth()
do {
  try firebaseAuth.signOut()
} catch let signOutError as NSError {
  print("Error signing out: %@", signOutError)
}

Objective-C

NSError *signOutError;
BOOL status = [[FIRAuth auth] signOut:&signOutError];
if (!status) {
  NSLog(@"Error signing out: %@", signOutError);
  return;
}

You may also want to add error handling code for the full range of authentication errors. See Handle Errors.