Laravel 8.x Authorization

Introduction

In addition to providing built-in authentication services, Laravel also provides a simple way to authorize user actions against a given resource. For example, even though a user is authenticated, they may not be authorized to update or delete certain Eloquent models or database records managed by your application. Laravel's authorization features provide an easy, organized way of managing these types of authorization checks.

Laravel provides two primary ways of authorizing actions: gates and policies. Think of gates and policies like routes and controllers. Gates provide a simple, closure-based approach to authorization while policies, like controllers, group logic around a particular model or resource. In this documentation, we'll explore gates first and then examine policies.

You do not need to choose between exclusively using gates or exclusively using policies when building an application. Most applications will most likely contain some mixture of gates and policies, and that is perfectly fine! Gates are most applicable to actions which are not related to any model or resource, such as viewing an administrator dashboard. In contrast, policies should be used when you wish to authorize an action for a particular model or resource.

Gates

Writing Gates

Note: Gates are a great way to learn the basics of Laravel's authorization features; however, when building robust Laravel applications you should consider using policies to organize your authorization rules.

Gates are simply closures that determine if a user is authorized to perform a given action. Typically, gates are defined within the boot method of the App\Providers\AuthServiceProvider class using the Gate facade. Gates always receive a user instance as their first argument and may optionally receive additional arguments such as a relevant Eloquent model.

In this example, we'll define a gate to determine if a user can update a given App\Models\Post model. The gate will accomplish this by comparing the user's id against the user_id of the user that created the post:

use App\Models\Post;
use App\Models\User;
use Illuminate\Support\Facades\Gate;

/**
 * Register any authentication / authorization services.
 *
 * @return void
 */
public function boot()
{
    $this->registerPolicies();

    Gate::define('update-post', function (User $user, Post $post) {
        return $user->id === $post->user_id;
    });
}

Like controllers, gates may also be defined using a class callback array:

use App\Policies\PostPolicy;
use Illuminate\Support\Facades\Gate;

/**
 * Register any authentication / authorization services.
 *
 * @return void
 */
public function boot()
{
    $this->registerPolicies();

    Gate::define('update-post', [PostPolicy::class, 'update']);
}

Authorizing Actions

To authorize an action using gates, you should use the allows or denies methods provided by the Gate facade. Note that you are not required to pass the currently authenticated user to these methods. Laravel will automatically take care of passing the user into the gate closure. It is typical to call the gate authorization methods within your application's controllers before performing an action that requires authorization:

<?php

namespace App\Http\Controllers;

use App\Http\Controllers\Controller;
use App\Models\Post;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Gate;

class PostController extends Controller
{
    /**
     * Update the given post.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \App\Models\Post  $post
     * @return \Illuminate\Http\Response
     */
    public function update(Request $request, Post $post)
    {
        if (! Gate::allows('update-post', $post)) {
            abort(403);
        }

        // Update the post...
    }
}

If you would like to determine if a user other than the currently authenticated user is authorized to perform an action, you may use the forUser method on the Gate facade:

if (Gate::forUser($user)->allows('update-post', $post)) {
    // The user can update the post...
}

if (Gate::forUser($user)->denies('update-post', $post)) {
    // The user can't update the post...
}

You may authorize multiple actions at a time using the any or none methods:

if (Gate::any(['update-post', 'delete-post'], $post)) {
    // The user can update or delete the post...
}

if (Gate::none(['update-post', 'delete-post'], $post)) {
    // The user can't update or delete the post...
}

Authorizing Or Throwing Exceptions

If you would like to attempt to authorize an action and automatically throw an Illuminate\Auth\Access\AuthorizationException if the user is not allowed to perform the given action, you may use the Gate facade's authorize method. Instances of AuthorizationException are automatically converted to a 403 HTTP response by Laravel's exception handler:

Gate::authorize('update-post', $post);

// The action is authorized...

Supplying Additional Context

The gate methods for authorizing abilities (allows, denies, check, any, none, authorize, can, cannot) and the authorization Blade directives (@can, @cannot, @canany) can receive an array as their second argument. These array elements are passed as parameters to the gate closure, and can be used for additional context when making authorization decisions:

use App\Models\Category;
use App\Models\User;
use Illuminate\Support\Facades\Gate;

Gate::define('create-post', function (User $user, Category $category, $pinned) {
    if (! $user->canPublishToGroup($category->group)) {
        return false;
    } elseif ($pinned && ! $user->canPinPosts()) {
        return false;
    }

    return true;
});

if (Gate::check('create-post', [$category, $pinned])) {
    // The user can create the post...
}

Gate Responses

So far, we have only examined gates that return simple boolean values. However, sometimes you may wish to return a more detailed response, including an error message. To do so, you may return an Illuminate\Auth\Access\Response from your gate:

use App\Models\User;
use Illuminate\Auth\Access\Response;
use Illuminate\Support\Facades\Gate;

Gate::define('edit-settings', function (User $user) {
    return $user->isAdmin
                ? Response::allow()
                : Response::deny('You must be an administrator.');
});

Even when you return an authorization response from your gate, the Gate::allows method will still return a simple boolean value; however, you may use the Gate::inspect method to get the full authorization response returned by the gate:

$response = Gate::inspect('edit-settings');

if ($response->allowed()) {
    // The action is authorized...
} else {
    echo $response->message();
}

When using the Gate::authorize method, which throws an AuthorizationException if the action is not authorized, the error message provided by the authorization response will be propagated to the HTTP response:

Gate::authorize('edit-settings');

// The action is authorized...

Intercepting Gate Checks

Sometimes, you may wish to grant all abilities to a specific user. You may use the before method to define a closure that is run before all other authorization checks:

use Illuminate\Support\Facades\Gate;

Gate::before(function ($user, $ability) {
    if ($user->isAdministrator()) {
        return true;
    }
});

If the before closure returns a non-null result that result will be considered the result of the authorization check.

You may use the after method to define a closure to be executed after all other authorization checks:

Gate::after(function ($user, $ability, $result, $arguments) {
    if ($user->isAdministrator()) {
        return true;
    }
});

Similar to the before method, if the after closure returns a non-null result that result will be considered the result of the authorization check.

Inline Authorization

Occasionally, you may wish to determine if the currently authenticated user is authorized to perform a given action without writing a dedicate gate that corresponds to the action. Laravel allows you to perform these types of "inline" authorization checks via the Gate::allowIf and Gate::denyIf methods:

use Illuminate\Support\Facades\Auth;

Gate::allowIf(fn ($user) => $user->isAdministrator());

Gate::denyIf(fn ($user) => $user->banned());

If the action is not authorized or if no user is currently authenticated, Laravel will automatically throw an Illuminate\Auth\Access\AuthorizationException exception. Instances of AuthorizationException are automatically converted to a 403 HTTP response by Laravel's exception handler:

Creating Policies

Generating Policies

Policies are classes that organize authorization logic around a particular model or resource. For example, if your application is a blog, you may have a App\Models\Post model and a corresponding App\Policies\PostPolicy to authorize user actions such as creating or updating posts.

You may generate a policy using the make:policy Artisan command. The generated policy will be placed in the app/Policies directory. If this directory does not exist in your application, Laravel will create it for you:

php artisan make:policy PostPolicy

The make:policy command will generate an empty policy class. If you would like to generate a class with example policy methods related to viewing, creating, updating, and deleting the resource, you may provide a --model option when executing the command:

php artisan make:policy PostPolicy --model=Post

Registering Policies

Once the policy class has been created, it needs to be registered. Registering policies is how we can inform Laravel which policy to use when authorizing actions against a given model type.

The App\Providers\AuthServiceProvider included with fresh Laravel applications contains a policies property which maps your Eloquent models to their corresponding policies. Registering a policy will instruct Laravel which policy to utilize when authorizing actions against a given Eloquent model:

<?php

namespace App\Providers;

use App\Models\Post;
use App\Policies\PostPolicy;
use Illuminate\Foundation\Support\Providers\AuthServiceProvider as ServiceProvider;
use Illuminate\Support\Facades\Gate;

class AuthServiceProvider extends ServiceProvider
{
    /**
     * The policy mappings for the application.
     *
     * @var array
     */
    protected $policies = [
        Post::class => PostPolicy::class,
    ];

    /**
     * Register any application authentication / authorization services.
     *
     * @return void
     */
    public function boot()
    {
        $this->registerPolicies();

        //
    }
}

Policy Auto-Discovery

Instead of manually registering model policies, Laravel can automatically discover policies as long as the model and policy follow standard Laravel naming conventions. Specifically, the policies must be in a Policies directory at or above the directory that contains your models. So, for example, the models may be placed in the app/Models directory while the policies may be placed in the app/Policies directory. In this situation, Laravel will check for policies in app/Models/Policies then app/Policies. In addition, the policy name must match the model name and have a Policy suffix. So, a User model would correspond to a UserPolicy policy class.

If you would like to define your own policy discovery logic, you may register a custom policy discovery callback using the Gate::guessPolicyNamesUsing method. Typically, this method should be called from the boot method of your application's AuthServiceProvider:

use Illuminate\Support\Facades\Gate;

Gate::guessPolicyNamesUsing(function ($modelClass) {
    // Return the name of the policy class for the given model...
});

Note: Any policies that are explicitly mapped in your AuthServiceProvider will take precedence over any potentially auto-discovered policies.

Writing Policies

Policy Methods

Once the policy class has been registered, you may add methods for each action it authorizes. For example, let's define an update method on our PostPolicy which determines if a given App\Models\User can update a given App\Models\Post instance.

The update method will receive a User and a Post instance as its arguments, and should return true or false indicating whether the user is authorized to update the given Post. So, in this example, we will verify that the user's id matches the user_id on the post:

<?php

namespace App\Policies;

use App\Models\Post;
use App\Models\User;

class PostPolicy
{
    /**
     * Determine if the given post can be updated by the user.
     *
     * @param  \App\Models\User  $user
     * @param  \App\Models\Post  $post
     * @return bool
     */
    public function update(User $user, Post $post)
    {
        return $user->id === $post->user_id;
    }
}

You may continue to define additional methods on the policy as needed for the various actions it authorizes. For example, you might define view or delete methods to authorize various Post related actions, but remember you are free to give your policy methods any name you like.

If you used the --model option when generating your policy via the Artisan console, it will already contain methods for the viewAny, view, create, update, delete, restore, and forceDelete actions.

Tip!! All policies are resolved via the Laravel service container, allowing you to type-hint any needed dependencies in the policy's constructor to have them automatically injected.

Policy Responses

So far, we have only examined policy methods that return simple boolean values. However, sometimes you may wish to return a more detailed response, including an error message. To do so, you may return an Illuminate\Auth\Access\Response instance from your policy method:

use App\Models\Post;
use App\Models\User;
use Illuminate\Auth\Access\Response;

/**
 * Determine if the given post can be updated by the user.
 *
 * @param  \App\Models\User  $user
 * @param  \App\Models\Post  $post
 * @return \Illuminate\Auth\Access\Response
 */
public function update(User $user, Post $post)
{
    return $user->id === $post->user_id
                ? Response::allow()
                : Response::deny('You do not own this post.');
}

When returning an authorization response from your policy, the Gate::allows method will still return a simple boolean value; however, you may use the Gate::inspect method to get the full authorization response returned by the gate:

use Illuminate\Support\Facades\Gate;

$response = Gate::inspect('update', $post);

if ($response->allowed()) {
    // The action is authorized...
} else {
    echo $response->message();
}

When using the Gate::authorize method, which throws an AuthorizationException if the action is not authorized, the error message provided by the authorization response will be propagated to the HTTP response:

Gate::authorize('update', $post);

// The action is authorized...

Methods Without Models

Some policy methods only receive an instance of the currently authenticated user. This situation is most common when authorizing create actions. For example, if you are creating a blog, you may wish to determine if a user is authorized to create any posts at all. In these situations, your policy method should only expect to receive a user instance:

/**
 * Determine if the given user can create posts.
 *
 * @param  \App\Models\User  $user
 * @return bool
 */
public function create(User $user)
{
    return $user->role == 'writer';
}

Guest Users

By default, all gates and policies automatically return false if the incoming HTTP request was not initiated by an authenticated user. However, you may allow these authorization checks to pass through to your gates and policies by declaring an "optional" type-hint or supplying a null default value for the user argument definition:

<?php

namespace App\Policies;

use App\Models\Post;
use App\Models\User;

class PostPolicy
{
    /**
     * Determine if the given post can be updated by the user.
     *
     * @param  \App\Models\User  $user
     * @param  \App\Models\Post  $post
     * @return bool
     */
    public function update(?User $user, Post $post)
    {
        return optional($user)->id === $post->user_id;
    }
}

Policy Filters

For certain users, you may wish to authorize all actions within a given policy. To accomplish this, define a before method on the policy. The before method will be executed before any other methods on the policy, giving you an opportunity to authorize the action before the intended policy method is actually called. This feature is most commonly used for authorizing application administrators to perform any action:

use App\Models\User;

/**
 * Perform pre-authorization checks.
 *
 * @param  \App\Models\User  $user
 * @param  string  $ability
 * @return void|bool
 */
public function before(User $user, $ability)
{
    if ($user->isAdministrator()) {
        return true;
    }
}

If you would like to deny all authorization checks for a particular type of user then you may return false from the before method. If null is returned, the authorization check will fall through to the policy method.

Note: The before method of a policy class will not be called if the class doesn't contain a method with a name matching the name of the ability being checked.

Authorizing Actions Using Policies

Via The User Model

The App\Models\User model that is included with your Laravel application includes two helpful methods for authorizing actions: can and cannot. The can and cannot methods receive the name of the action you wish to authorize and the relevant model. For example, let's determine if a user is authorized to update a given App\Models\Post model. Typically, this will be done within a controller method:

<?php

namespace App\Http\Controllers;

use App\Http\Controllers\Controller;
use App\Models\Post;
use Illuminate\Http\Request;

class PostController extends Controller
{
    /**
     * Update the given post.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \App\Models\Post  $post
     * @return \Illuminate\Http\Response
     */
    public function update(Request $request, Post $post)
    {
        if ($request->user()->cannot('update', $post)) {
            abort(403);
        }

        // Update the post...
    }
}

If a policy is registered for the given model, the can method will automatically call the appropriate policy and return the boolean result. If no policy is registered for the model, the can method will attempt to call the closure-based Gate matching the given action name.

Actions That Don't Require Models

Remember, some actions may correspond to policy methods like create that do not require a model instance. In these situations, you may pass a class name to the can method. The class name will be used to determine which policy to use when authorizing the action:

<?php

namespace App\Http\Controllers;

use App\Http\Controllers\Controller;
use App\Models\Post;
use Illuminate\Http\Request;

class PostController extends Controller
{
    /**
     * Create a post.
     *
     * @param  \Illuminate\Http\Request  $request
     * @return \Illuminate\Http\Response
     */
    public function store(Request $request)
    {
        if ($request->user()->cannot('create', Post::class)) {
            abort(403);
        }

        // Create the post...
    }
}

Via Controller Helpers

In addition to helpful methods provided to the App\Models\User model, Laravel provides a helpful authorize method to any of your controllers which extend the App\Http\Controllers\Controller base class.

Like the can method, this method accepts the name of the action you wish to authorize and the relevant model. If the action is not authorized, the authorize method will throw an Illuminate\Auth\Access\AuthorizationException exception which the Laravel exception handler will automatically convert to an HTTP response with a 403 status code:

<?php

namespace App\Http\Controllers;

use App\Http\Controllers\Controller;
use App\Models\Post;
use Illuminate\Http\Request;

class PostController extends Controller
{
    /**
     * Update the given blog post.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \App\Models\Post  $post
     * @return \Illuminate\Http\Response
     *
     * @throws \Illuminate\Auth\Access\AuthorizationException
     */
    public function update(Request $request, Post $post)
    {
        $this->authorize('update', $post);

        // The current user can update the blog post...
    }
}

Actions That Don't Require Models

As previously discussed, some policy methods like create do not require a model instance. In these situations, you should pass a class name to the authorize method. The class name will be used to determine which policy to use when authorizing the action:

use App\Models\Post;
use Illuminate\Http\Request;

/**
 * Create a new blog post.
 *
 * @param  \Illuminate\Http\Request  $request
 * @return \Illuminate\Http\Response
 *
 * @throws \Illuminate\Auth\Access\AuthorizationException
 */
public function create(Request $request)
{
    $this->authorize('create', Post::class);

    // The current user can create blog posts...
}

Authorizing Resource Controllers

If you are utilizing resource controllers, you may make use of the authorizeResource method in your controller's constructor. This method will attach the appropriate can middleware definitions to the resource controller's methods.

The authorizeResource method accepts the model's class name as its first argument, and the name of the route / request parameter that will contain the model's ID as its second argument. You should ensure your resource controller is created using the --model flag so that it has the required method signatures and type hints:

<?php

namespace App\Http\Controllers;

use App\Http\Controllers\Controller;
use App\Models\Post;
use Illuminate\Http\Request;

class PostController extends Controller
{
    /**
     * Create the controller instance.
     *
     * @return void
     */
    public function __construct()
    {
        $this->authorizeResource(Post::class, 'post');
    }
}

The following controller methods will be mapped to their corresponding policy method. When requests are routed to the given controller method, the corresponding policy method will automatically be invoked before the controller method is executed:

Tip!! You may use the make:policy command with the --model option to quickly generate a policy class for a given model: php artisan make:policy PostPolicy --model=Post.

Via Middleware

Laravel includes a middleware that can authorize actions before the incoming request even reaches your routes or controllers. By default, the Illuminate\Auth\Middleware\Authorize middleware is assigned the can key in your App\Http\Kernel class. Let's explore an example of using the can middleware to authorize that a user can update a post:

use App\Models\Post;

Route::put('/post/{post}', function (Post $post) {
    // The current user may update the post...
})->middleware('can:update,post');

In this example, we're passing the can middleware two arguments. The first is the name of the action we wish to authorize and the second is the route parameter we wish to pass to the policy method. In this case, since we are using implicit model binding, a App\Models\Post model will be passed to the policy method. If the user is not authorized to perform the given action, an HTTP response with a 403 status code will be returned by the middleware.

For convenience, you may also attach the can middleware to your route using the can method:

use App\Models\Post;

Route::put('/post/{post}', function (Post $post) {
    // The current user may update the post...
})->can('update', 'post');

Actions That Don't Require Models

Again, some policy methods like create do not require a model instance. In these situations, you may pass a class name to the middleware. The class name will be used to determine which policy to use when authorizing the action:

Route::post('/post', function () {
    // The current user may create posts...
})->middleware('can:create,App\Models\Post');

Specifying the entire class name within a string middleware definition can become cumbersome. For that reason, you may choose to attach the can middleware to your route using the can method:

use App\Models\Post;

Route::post('/post', function () {
    // The current user may create posts...
})->can('create', Post::class);

Via Blade Templates

When writing Blade templates, you may wish to display a portion of the page only if the user is authorized to perform a given action. For example, you may wish to show an update form for a blog post only if the user can actually update the post. In this situation, you may use the @can and @cannot directives:

@can('update', $post)
    <!-- The current user can update the post... -->
@elsecan('create', App\Models\Post::class)
    <!-- The current user can create new posts... -->
@else
    <!-- ... -->
@endcan

@cannot('update', $post)
    <!-- The current user cannot update the post... -->
@elsecannot('create', App\Models\Post::class)
    <!-- The current user cannot create new posts... -->
@endcannot

These directives are convenient shortcuts for writing @if and @unless statements. The @can and @cannot statements above are equivalent to the following statements:

@if (Auth::user()->can('update', $post))
    <!-- The current user can update the post... -->
@endif

@unless (Auth::user()->can('update', $post))
    <!-- The current user cannot update the post... -->
@endunless

You may also determine if a user is authorized to perform any action from a given array of actions. To accomplish this, use the @canany directive:

@canany(['update', 'view', 'delete'], $post)
    <!-- The current user can update, view, or delete the post... -->
@elsecanany(['create'], \App\Models\Post::class)
    <!-- The current user can create a post... -->
@endcanany

Actions That Don't Require Models

Like most of the other authorization methods, you may pass a class name to the @can and @cannot directives if the action does not require a model instance:

@can('create', App\Models\Post::class)
    <!-- The current user can create posts... -->
@endcan

@cannot('create', App\Models\Post::class)
    <!-- The current user can't create posts... -->
@endcannot

Supplying Additional Context

When authorizing actions using policies, you may pass an array as the second argument to the various authorization functions and helpers. The first element in the array will be used to determine which policy should be invoked, while the rest of the array elements are passed as parameters to the policy method and can be used for additional context when making authorization decisions. For example, consider the following PostPolicy method definition which contains an additional $category parameter:

/**
 * Determine if the given post can be updated by the user.
 *
 * @param  \App\Models\User  $user
 * @param  \App\Models\Post  $post
 * @param  int  $category
 * @return bool
 */
public function update(User $user, Post $post, int $category)
{
    return $user->id === $post->user_id &&
           $user->canUpdateCategory($category);
}

When attempting to determine if the authenticated user can update a given post, we can invoke this policy method like so:

/**
 * Update the given blog post.
 *
 * @param  \Illuminate\Http\Request  $request
 * @param  \App\Models\Post  $post
 * @return \Illuminate\Http\Response
 *
 * @throws \Illuminate\Auth\Access\AuthorizationException
 */
public function update(Request $request, Post $post)
{
    $this->authorize('update', [$post, $request->category]);

    // The current user can update the blog post...
}