Laravel 8.x Laravel Sanctum

Introduction

Laravel Sanctum provides a featherweight authentication system for SPAs (single page applications), mobile applications, and simple, token based APIs. Sanctum allows each user of your application to generate multiple API tokens for their account. These tokens may be granted abilities / scopes which specify which actions the tokens are allowed to perform.

How It Works

Laravel Sanctum exists to solve two separate problems. Let's discuss each before digging deeper into the library.

API Tokens

First, Sanctum is a simple package you may use to issue API tokens to your users without the complication of OAuth. This feature is inspired by GitHub and other applications which issue "personal access tokens". For example, imagine the "account settings" of your application has a screen where a user may generate an API token for their account. You may use Sanctum to generate and manage those tokens. These tokens typically have a very long expiration time (years), but may be manually revoked by the user at anytime.

Laravel Sanctum offers this feature by storing user API tokens in a single database table and authenticating incoming HTTP requests via the Authorization header which should contain a valid API token.

SPA Authentication

Second, Sanctum exists to offer a simple way to authenticate single page applications (SPAs) that need to communicate with a Laravel powered API. These SPAs might exist in the same repository as your Laravel application or might be an entirely separate repository, such as a SPA created using Vue CLI or a Next.js application.

For this feature, Sanctum does not use tokens of any kind. Instead, Sanctum uses Laravel's built-in cookie based session authentication services. Typically, Sanctum utilizes Laravel's web authentication guard to accomplish this. This provides the benefits of CSRF protection, session authentication, as well as protects against leakage of the authentication credentials via XSS.

Sanctum will only attempt to authenticate using cookies when the incoming request originates from your own SPA frontend. When Sanctum examines an incoming HTTP request, it will first check for an authentication cookie and, if none is present, Sanctum will then examine the Authorization header for a valid API token.

lightbulb">Tip!! It is perfectly fine to use Sanctum only for API token authentication or only for SPA authentication. Just because you use Sanctum does not mean you are required to use both features it offers.

Installation

lightbulb">Tip!! The most recent versions of Laravel already include Laravel Sanctum. However, if your application's composer.json file does not include laravel/sanctum, you may follow the installation instructions below.

You may install Laravel Sanctum via the Composer package manager:

composer require laravel/sanctum

Next, you should publish the Sanctum configuration and migration files using the vendor:publish Artisan command. The sanctum configuration file will be placed in your application's config directory:

php artisan vendor:publish --provider="Laravel\Sanctum\SanctumServiceProvider"

Finally, you should run your database migrations. Sanctum will create one database table in which to store API tokens:

php artisan migrate

Next, if you plan to utilize Sanctum to authenticate an SPA, you should add Sanctum's middleware to your api middleware group within your application's app/Http/Kernel.php file:

'api' => [
    \Laravel\Sanctum\Http\Middleware\EnsureFrontendRequestsAreStateful::class,
    'throttle:api',
    \Illuminate\Routing\Middleware\SubstituteBindings::class,
],

Migration Customization

If you are not going to use Sanctum's default migrations, you should call the Sanctum::ignoreMigrations method in the register method of your App\Providers\AppServiceProvider class. You may export the default migrations by executing the following command: php artisan vendor:publish --tag=sanctum-migrations

Configuration

Overriding Default Models

Although not typically required, you are free to extend the PersonalAccessToken model used internally by Sanctum:

use Laravel\Sanctum\PersonalAccessToken as SanctumPersonalAccessToken;

class PersonalAccessToken extends SanctumPersonalAccessToken
{
    // ...
}

Then, you may instruct Sanctum to use your custom model via the usePersonalAccessTokenModel method provided by Sanctum. Typically, you should call this method in the boot method of one of your application's service providers:

use App\Models\Sanctum\PersonalAccessToken;
use Laravel\Sanctum\Sanctum;

/**
 * Bootstrap any application services.
 *
 * @return void
 */
public function boot()
{
    Sanctum::usePersonalAccessTokenModel(PersonalAccessToken::class);
}

API Token Authentication

lightbulb">Tip!! You should not use API tokens to authenticate your own first-party SPA. Instead, use Sanctum's built-in SPA authentication features.

Issuing API Tokens

Sanctum allows you to issue API tokens / personal access tokens that may be used to authenticate API requests to your application. When making requests using API tokens, the token should be included in the Authorization header as a Bearer token.

To begin issuing tokens for users, your User model should use the Laravel\Sanctum\HasApiTokens trait:

use Laravel\Sanctum\HasApiTokens;

class User extends Authenticatable
{
    use HasApiTokens, HasFactory, Notifiable;
}

To issue a token, you may use the createToken method. The createToken method returns a Laravel\Sanctum\NewAccessToken instance. API tokens are hashed using SHA-256 hashing before being stored in your database, but you may access the plain-text value of the token using the plainTextToken property of the NewAccessToken instance. You should display this value to the user immediately after the token has been created:

use Illuminate\Http\Request;

Route::post('/tokens/create', function (Request $request) {
    $token = $request->user()->createToken($request->token_name);

    return ['token' => $token->plainTextToken];
});

You may access all of the user's tokens using the tokens Eloquent relationship provided by the HasApiTokens trait:

foreach ($user->tokens as $token) {
    //
}

Token Abilities

Sanctum allows you to assign "abilities" to tokens. Abilities serve a similar purpose as OAuth's "scopes". You may pass an array of string abilities as the second argument to the createToken method:

return $user->createToken('token-name', ['server:update'])->plainTextToken;

When handling an incoming request authenticated by Sanctum, you may determine if the token has a given ability using the tokenCan method:

if ($user->tokenCan('server:update')) {
    //
}

Token Ability Middleware

Sanctum also includes two middleware that may be used to verify that an incoming request is authenticated with a token that has been granted a given ability. To get started, add the following middleware to the $routeMiddleware property of your application's app/Http/Kernel.php file:

'abilities' => \Laravel\Sanctum\Http\Middleware\CheckAbilities::class,
'ability' => \Laravel\Sanctum\Http\Middleware\CheckForAnyAbility::class,

The abilities middleware may be assigned to a route to verify that the incoming request's token has all of the listed abilities:

Route::get('/orders', function () {
    // Token has both "check-status" and "place-orders" abilities...
})->middleware(['auth:sanctum', 'abilities:check-status,place-orders']);

The ability middleware may be assigned to a route to verify that the incoming request's token has at least one of the listed abilities:

Route::get('/orders', function () {
    // Token has the "check-status" or "place-orders" ability...
})->middleware(['auth:sanctum', 'ability:check-status,place-orders']);

First-Party UI Initiated Requests

For convenience, the tokenCan method will always return true if the incoming authenticated request was from your first-party SPA and you are using Sanctum's built-in SPA authentication.

However, this does not necessarily mean that your application has to allow the user to perform the action. Typically, your application's authorization policies will determine if the token has been granted the permission to perform the abilities as well as check that the user instance itself should be allowed to perform the action.

For example, if we imagine an application that manages servers, this might mean checking that token is authorized to update servers and that the server belongs to the user:

return $request->user()->id === $server->user_id &&
       $request->user()->tokenCan('server:update')

At first, allowing the tokenCan method to be called and always return true for first-party UI initiated requests may seem strange; however, it is convenient to be able to always assume an API token is available and can be inspected via the tokenCan method. By taking this approach, you may always call the tokenCan method within your application's authorizations policies without worrying about whether the request was triggered from your application's UI or was initiated by one of your API's third-party consumers.

Protecting Routes

To protect routes so that all incoming requests must be authenticated, you should attach the sanctum authentication guard to your protected routes within your routes/web.php and routes/api.php route files. This guard will ensure that incoming requests are authenticated as either stateful, cookie authenticated requests or contain a valid API token header if the request is from a third party.

You may be wondering why we suggest that you authenticate the routes within your application's routes/web.php file using the sanctum guard. Remember, Sanctum will first attempt to authenticate incoming requests using Laravel's typical session authentication cookie. If that cookie is not present then Sanctum will attempt to authenticate the request using a token in the request's Authorization header. In addition, authenticating all requests using Sanctum ensures that we may always call the tokenCan method on the currently authenticated user instance:

use Illuminate\Http\Request;

Route::middleware('auth:sanctum')->get('/user', function (Request $request) {
    return $request->user();
});

Revoking Tokens

You may "revoke" tokens by deleting them from your database using the tokens relationship that is provided by the Laravel\Sanctum\HasApiTokens trait:

// Revoke all tokens...
$user->tokens()->delete();

// Revoke the token that was used to authenticate the current request...
$request->user()->currentAccessToken()->delete();

// Revoke a specific token...
$user->tokens()->where('id', $tokenId)->delete();

SPA Authentication

Sanctum also exists to provide a simple method of authenticating single page applications (SPAs) that need to communicate with a Laravel powered API. These SPAs might exist in the same repository as your Laravel application or might be an entirely separate repository.

For this feature, Sanctum does not use tokens of any kind. Instead, Sanctum uses Laravel's built-in cookie based session authentication services. This approach to authentication provides the benefits of CSRF protection, session authentication, as well as protects against leakage of the authentication credentials via XSS.

Note: note In order to authenticate, your SPA and API must share the same top-level domain. However, they may be placed on different subdomains. Additionally, you should ensure that you send the Accept: application/json header with your request.

Configuration

Configuring Your First-Party Domains

First, you should configure which domains your SPA will be making requests from. You may configure these domains using the stateful configuration option in your sanctum configuration file. This configuration setting determines which domains will maintain "stateful" authentication using Laravel session cookies when making requests to your API.

Note: note If you are accessing your application via a URL that includes a port (127.0.0.1:8000), you should ensure that you include the port number with the domain.

Sanctum Middleware

Next, you should add Sanctum's middleware to your api middleware group within your app/Http/Kernel.php file. This middleware is responsible for ensuring that incoming requests from your SPA can authenticate using Laravel's session cookies, while still allowing requests from third parties or mobile applications to authenticate using API tokens:

'api' => [
    \Laravel\Sanctum\Http\Middleware\EnsureFrontendRequestsAreStateful::class,
    'throttle:api',
    \Illuminate\Routing\Middleware\SubstituteBindings::class,
],

CORS & Cookies

If you are having trouble authenticating with your application from a SPA that executes on a separate subdomain, you have likely misconfigured your CORS (Cross-Origin Resource Sharing) or session cookie settings.

You should ensure that your application's CORS configuration is returning the Access-Control-Allow-Credentials header with a value of True. This may be accomplished by setting the supports_credentials option within your application's config/cors.php configuration file to true.

In addition, you should enable the withCredentials option on your application's global axios instance. Typically, this should be performed in your resources/js/bootstrap.js file. If you are not using Axios to make HTTP requests from your frontend, you should perform the equivalent configuration on your own HTTP client:

axios.defaults.withCredentials = true;

Finally, you should ensure your application's session cookie domain configuration supports any subdomain of your root domain. You may accomplish this by prefixing the domain with a leading . within your application's config/session.php configuration file:

'domain' => '.domain.com',

Authenticating

CSRF Protection

To authenticate your SPA, your SPA's "login" page should first make a request to the /sanctum/csrf-cookie endpoint to initialize CSRF protection for the application:

axios.get('/sanctum/csrf-cookie').then(response => {
    // Login...
});

During this request, Laravel will set an XSRF-TOKEN cookie containing the current CSRF token. This token should then be passed in an X-XSRF-TOKEN header on subsequent requests, which some HTTP client libraries like Axios and the Angular HttpClient will do automatically for you. If your JavaScript HTTP library does not set the value for you, you will need to manually set the X-XSRF-TOKEN header to match the value of the XSRF-TOKEN cookie that is set by this route.

Logging In

Once CSRF protection has been initialized, you should make a POST request to your Laravel application's /login route. This /login route may be implemented manually or using a headless authentication package like Laravel Fortify.

If the login request is successful, you will be authenticated and subsequent requests to your application's routes will automatically be authenticated via the session cookie that the Laravel application issued to your client. In addition, since your application already made a request to the /sanctum/csrf-cookie route, subsequent requests should automatically receive CSRF protection as long as your JavaScript HTTP client sends the value of the XSRF-TOKEN cookie in the X-XSRF-TOKEN header.

Of course, if your user's session expires due to lack of activity, subsequent requests to the Laravel application may receive 401 or 419 HTTP error response. In this case, you should redirect the user to your SPA's login page.

Note: note You are free to write your own /login endpoint; however, you should ensure that it authenticates the user using the standard, session based authentication services that Laravel provides. Typically, this means using the web authentication guard.

Protecting Routes

To protect routes so that all incoming requests must be authenticated, you should attach the sanctum authentication guard to your API routes within your routes/api.php file. This guard will ensure that incoming requests are authenticated as either a stateful authenticated requests from your SPA or contain a valid API token header if the request is from a third party:

use Illuminate\Http\Request;

Route::middleware('auth:sanctum')->get('/user', function (Request $request) {
    return $request->user();
});

Authorizing Private Broadcast Channels

If your SPA needs to authenticate with private / presence broadcast channels, you should place the Broadcast::routes method call within your routes/api.php file:

Broadcast::routes(['middleware' => ['auth:sanctum']]);

Next, in order for Pusher's authorization requests to succeed, you will need to provide a custom Pusher authorizer when initializing Laravel Echo. This allows your application to configure Pusher to use the axios instance that is properly configured for cross-domain requests:

window.Echo = new Echo({
    broadcaster: "pusher",
    cluster: process.env.MIX_PUSHER_APP_CLUSTER,
    encrypted: true,
    key: process.env.MIX_PUSHER_APP_KEY,
    authorizer: (channel, options) => {
        return {
            authorize: (socketId, callback) => {
                axios.post('/api/broadcasting/auth', {
                    socket_id: socketId,
                    channel_name: channel.name
                })
                .then(response => {
                    callback(false, response.data);
                })
                .catch(error => {
                    callback(true, error);
                });
            }
        };
    },
})

Mobile Application Authentication

You may also use Sanctum tokens to authenticate your mobile application's requests to your API. The process for authenticating mobile application requests is similar to authenticating third-party API requests; however, there are small differences in how you will issue the API tokens.

Issuing API Tokens

To get started, create a route that accepts the user's email / username, password, and device name, then exchanges those credentials for a new Sanctum token. The "device name" given to this endpoint is for informational purposes and may be any value you wish. In general, the device name value should be a name the user would recognize, such as "Nuno's iPhone 12".

Typically, you will make a request to the token endpoint from your mobile application's "login" screen. The endpoint will return the plain-text API token which may then be stored on the mobile device and used to make additional API requests:

use App\Models\User;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Hash;
use Illuminate\Validation\ValidationException;

Route::post('/sanctum/token', function (Request $request) {
    $request->validate([
        'email' => 'required|email',
        'password' => 'required',
        'device_name' => 'required',
    ]);

    $user = User::where('email', $request->email)->first();

    if (! $user || ! Hash::check($request->password, $user->password)) {
        throw ValidationException::withMessages([
            'email' => ['The provided credentials are incorrect.'],
        ]);
    }

    return $user->createToken($request->device_name)->plainTextToken;
});

When the mobile application uses the token to make an API request to your application, it should pass the token in the Authorization header as a Bearer token.

lightbulb">Tip!! When issuing tokens for a mobile application, you are also free to specify token abilities.

Protecting Routes

As previously documented, you may protect routes so that all incoming requests must be authenticated by attaching the sanctum authentication guard to the routes:

Route::middleware('auth:sanctum')->get('/user', function (Request $request) {
    return $request->user();
});

Revoking Tokens

To allow users to revoke API tokens issued to mobile devices, you may list them by name, along with a "Revoke" button, within an "account settings" portion of your web application's UI. When the user clicks the "Revoke" button, you can delete the token from the database. Remember, you can access a user's API tokens via the tokens relationship provided by the Laravel\Sanctum\HasApiTokens trait:

// Revoke all tokens...
$user->tokens()->delete();

// Revoke a specific token...
$user->tokens()->where('id', $tokenId)->delete();

Testing

While testing, the Sanctum::actingAs method may be used to authenticate a user and specify which abilities should be granted to their token:

use App\Models\User;
use Laravel\Sanctum\Sanctum;

public function test_task_list_can_be_retrieved()
{
    Sanctum::actingAs(
        User::factory()->create(),
        ['view-tasks']
    );

    $response = $this->get('/api/task');

    $response->assertOk();
}

If you would like to grant all abilities to the token, you should include * in the ability list provided to the actingAs method:

Sanctum::actingAs(
    User::factory()->create(),
    ['*']
);