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:
- In the
Firebase console
, open
the
Auth
section.
- 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];
- 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 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: 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
.