The basics
Serverpod automatically checks if the user is logged in and if the user has the right privileges to access the endpoint. When using the serverpod_auth
module you will not have to worry about keeping track of tokens, refreshing them or, even including them in requests as this all happens automatically under the hood.
The Session
object provides information about the current user. A unique userIdentifier
identifies a user. You should use this id whenever you a referring to a user. Access the id of a signed-in user through the authenticated
asynchronous getter of the Session
object. Since the default implementation of serverpod_auth
uses numeric IDs for the users, there is a convenience getter userId
on the AuthenticationInfo
, which returns the integer value.
Future<void> myMethod(Session session) async {
final authenticationInfo = await session.authenticated;
final userIdentifier = authenticationInfo?.userIdentifier;
final userId = authenticationInfo?.userId;
...
}
You can also use the Session object to check if a user is authenticated:
Future<void> myMethod(Session session) async {
var isSignedIn = await session.isUserSignedIn;
...
}
Requiring authentication on endpoints
It is common to want to restrict access to an endpoint to users that have signed in. You can do this by overriding the requireLogin
property of the Endpoint
class.
class MyEndpoint extends Endpoint {
bool get requireLogin => true;
Future<void> myMethod(Session session) async {
...
}
...
}
Explicitly allowing unauthenticated access
In some cases, you may want to explicitly allow certain endpoints or methods to be accessed without authentication. Serverpod provides the @unauthenticatedClientCall
annotation for this purpose.
When an endpoint or method is annotated with @unauthenticatedClientCall
:
- No authentication will be added to the header on the client when calling it.
- The server will receive calls as if there is no user signed in.
Under the hood, the @unauthenticatedClientCall
annotation makes the client omit authentication headers for calls to the annotated endpoint or method. On the server side, it ensures that the session is treated as unauthenticated for those calls, regardless of any existing authentication state.
You can use this annotation in two ways:
- On the entire endpoint class to make all methods unauthenticated:
class UnauthenticatedEndpoint extends Endpoint {
Future<bool> someMethod(Session session) async {
return session.isUserSignedIn; // Will always return false
}
Stream<bool> someStream(Session session) async* {
yield await session.isUserSignedIn; // Will always return false
}
}
- On specific methods to make only those methods unauthenticated:
class PartiallyUnauthenticatedEndpoint extends Endpoint {
Future<bool> publicMethod(Session session) async {
return session.isUserSignedIn; // Will always return false
}
Future<bool> authenticatedMethod(Session session) async {
return session.isUserSignedIn;
}
}
This is particularly useful for endpoints that must not receive authentication, such as JWT refresh endpoints.
Using @unauthenticatedClientCall
on an endpoint or method that also has requireLogin
set to true will lead to a conflict. Since the client will suppress sending authentication information, but the server will expect it, calls to such endpoints or methods will always fail with an authentication error.
Authorization on endpoints
Serverpod also supports scopes for restricting access. One or more scopes can be associated with a user. For instance, this can be used to give admin access to a specific user. To restrict access for an endpoint, override the requiredScopes
property. Note that setting requiredScopes
implicitly sets requireLogin
to true.
class MyEndpoint extends Endpoint {
bool get requireLogin => true;
Set<Scope> get requiredScopes => {Scope.admin};
Future<void> myMethod(Session session) async {
...
}
...
}
Managing scopes
New users are created without any scopes. To update a user's scopes, use the Users
class's updateUserScopes
method (requires the serverpod_auth_server
package). This method replaces all previously stored scopes.
await Users.updateUserScopes(session, userId, {Scope.admin});
Custom scopes
You may need more granular access control for specific endpoints. To create custom scopes, extend the Scope class, as shown below:
class CustomScope extends Scope {
const CustomScope(String name) : super(name);
static const userRead = CustomScope('userRead');
static const userWrite = CustomScope('userWrite');
}
Then use the custom scopes like this:
class MyEndpoint extends Endpoint {
bool get requireLogin => true;
Set<Scope> get requiredScopes => {CustomScope.userRead, CustomScope.userWrite};
Future<void> myMethod(Session session) async {
...
}
...
}
Keep in mind that a scope is merely an arbitrary string and can be written in any format you prefer. However, it's crucial to use unique strings for each scope, as duplicated scope strings may lead to unintentional data exposure.
User authentication
The StatusEndpoint
class includes methods for handling user sign-outs, whether from a single device or all devices.
In addition to the StatusEndpoint
methods, Serverpod provides more comprehensive tools for managing user authentication and sign-out processes across multiple devices.
For more detailed information on managing and revoking authentication keys, please refer to the Revoking authentication keys section.
Sign out device
To sign out a single device:
await client.modules.auth.status.signOutDevice();
This status endpoint method obtains the authentication key from session's authentication information, then revokes that key.
Sign out all devices
To sign the user out across all devices:
await client.modules.auth.status.signOutAllDevices();
This status endpoint retrieves the user ID from session's authentication information, then revokes all authentication keys related to that user.
The signOut
status endpoint is deprecated. Use signOutDevice
or signOutAllDevices
instead.
await client.modules.auth.status.signOut(); // Deprecated
The behavior of signOut
is controlled by legacyUserSignOutBehavior
, which you can adjust in the configure authentication section. This allows you to control the signout behaviour of already shipped clients.