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Serverpod comes with built-in user management and authentication. It is possible to build a custom authentication implementation, but the recommended way to authenticate users is to use the serverpod_auth module. The module makes it easy to authenticate with email or social sign-ins and currently supports signing in with email, Google, Apple, and Firebase.

Future versions of the authentication module will include more options. If you write another authentication module, please consider contributing your code.

with Serverpod

Installing the auth module

Serverpod's auth module makes it easy to authenticate users through email or 3rd parties. The authentication module also handles basic user information, such as user names and profile pictures. Make sure to use the same version numbers as for Serverpod itself for all dependencies.

Server setup

Add the module as a dependency to the server project's pubspec.yaml.

$ dart pub add serverpod_auth_server

Add the authentication handler to the Serverpod instance.

import 'package:serverpod_auth_server/serverpod_auth_server.dart' as auth;

void run(List<String> args) async {
var pod = Serverpod(
authenticationHandler: auth.authenticationHandler, // Add this line


Optionally, add a nickname for the module in the config/generator.yaml file. This nickname will be used as the name of the module in the code.

nickname: auth

While still in the server project, generate the client code and endpoint methods for the auth module by running the serverpod generate command line tool.

$ serverpod generate

Initialize the auth database

After adding the module to the server project, you need to initialize the database. First you have to create a new migration that includes the auth module tables. This is done by running the serverpod create-migration command line tool in the server project.

$ serverpod create-migration

Start your database container from the server project.

$ docker-compose up --build --detach

Then apply the migration by starting the server with the apply-migrations flag.

$ dart run bin/main.dart --role maintenance --apply-migrations

The full migration instructions can be found in the migration guide.

Configure Authentication

Serverpod's auth module comes with a default Authentication Configuration. To customize it, go to your main server.dart file, import the serverpod_auth_server module and set up the authentication configuration:

import 'package:serverpod_auth_server/module.dart' as auth;  

void run(List<String> args) async {

minPasswordLength: 12,

// Start the Serverpod server.
await pod.start();

maxAllowedEmailSignInAttemptsMax allowed failed email sign in attempts within the reset period.5
emailSignInFailureResetTimeThe reset period for email sign in attempts. Defaults to 5 minutes.5min
userCanEditUserImageTrue if users can update their profile images.true
userCanEditUserNameTrue if users can edit their user names.true
userCanEditFullNameTrue if users can view their user name.true
userCanSeeUserNameTrue if users can view their user name.true
userCanSeeFullNameTrue if users can view their full name.true
enableUserImagesTrue if user images are enabled.true
importUserImagesFromGoogleSignInTrue if user images should be imported when signing in with Google.true
userImageSizeThe size of user images.256
userImageFormatThe format used to store user imagesjpg
userImageQualityThe quality setting for images if JPG format is used.70
userImageGeneratorGenerator used to produce default user images.-
userInfoCacheLifetimeThe duration which user infos are cached locally in the server.1min
onUserWillBeCreatedCalled when a user is about to be created, gives a chance to abort the creation by returning false.-
onUserCreatedCalled after a user has been created. Listen to this callback if you need to do additional setup.-
onUserUpdatedCalled whenever a user has been updated. This can be when the user name is changed or if the user uploads a new profile picture.-
sendPasswordResetEmailCalled when a user should be sent a reset code by email.-
sendValidationEmailCalled when a user should be sent a validation code on account setup.-
validationCodeLengthThe length of the validation code used in the authentication process. This value determines the number of digits in the validation code. Setting this value to less than 3 reduces security.8
passwordResetExpirationTimeThe time for password resets to be valid.24h
extraSaltyHashTrue if the server should use the accounts email address as part of the salt when storing password hashes (strongly recommended).true
firebaseServiceAccountKeyJsonFirebase service account key JSON file. Generate and download from the Firebase console.-
maxPasswordLengthThe maximum length of passwords when signing up with email.128
minPasswordLengthThe minimum length of passwords when signing up with email.8
allowUnsecureRandomTrue if unsecure random number generation is allowed. If set to false, an error will be thrown if the platform does not support secure random number generation.false

Client setup

Add the auth client in your client project's pubspec.yaml.

serverpod_auth_client: ^1.x.x

App setup

First, add dependencies to your app's pubspec.yaml file for the methods of signing in that you want to support.

sdk: flutter
serverpod_flutter: ^1.x.x
path: ../auth_example_client

serverpod_auth_shared_flutter: ^1.x.x

Next, you need to set up a SessionManager, which keeps track of the user's state. It will also handle the authentication keys passed to the client from the server, upload user profile images, etc.

late SessionManager sessionManager;
late Client client;

void main() async {
// Need to call this as we are using Flutter bindings before runApp is called.

// The android emulator does not have access to the localhost of the machine.
// const ipAddress = ''; // Android emulator ip for the host

// On a real device replace the ipAddress with the IP address of your computer.
const ipAddress = 'localhost';

// Sets up a singleton client object that can be used to talk to the server from
// anywhere in our app. The client is generated from your server code.
// The client is set up to connect to a Serverpod running on a local server on
// the default port. You will need to modify this to connect to staging or
// production servers.
client = Client(
authenticationKeyManager: FlutterAuthenticationKeyManager(),
)..connectivityMonitor = FlutterConnectivityMonitor();

// The session manager keeps track of the signed-in state of the user. You
// can query it to see if the user is currently signed in and get information
// about the user.
sessionManager = SessionManager(
caller: client.modules.auth,
await sessionManager.initialize();


The SessionManager has useful methods for viewing and monitoring the user's current state:

  • The signedInUser will return a UserInfo if the user is currently signed in (or null if the user isn't signed in).
  • Use the addListener method to get notified of changes to the user's signed in state.
  • Sign out a user by calling the signOut method.

For example it can be useful to subscribe to changes in the SessionManager and force a rerender of your app.

void initState() {

// Rebuild the page if signed in status changes.
sessionManager.addListener(() {
setState(() {});