Guards and Policies

Guards and Policies in Laravel provide a robust system for managing authentication and authorization. Guards handle how users are authenticated, while Policies encapsulate the authorization logic for specific resources or actions.

Origin

Guards and Policies are part of Laravel's comprehensive authentication and authorization system, introduced to offer flexible, scalable solutions for user and resource management.

Why are they important?

1. Role-Based Access Control: Policies enforce user permissions at the resource level.
2. Custom Authentication: Guards allow different authentication methods (e.g., web and API).
3. Cleaner Code: Offload logic from controllers into dedicated classes.

Best Practices

1. Map Policies to Models: Register policies in AuthServiceProvider for seamless integration.
2. Use Guards for Segmentation: Create separate guards for different user types.
3. Combine with Middleware: Use middleware for route-level access control.

Example in Action

Define a guard for API users in config/auth.php:

'guards' => [
    'api' => [
        'driver' => 'token',
        'provider' => 'users',
    ],
],

Create a policy for the Post model:

php artisan make:policy PostPolicy

In the policy:

public function update(User $user, Post $post)
{
    return $user->id === $post->user_id;
}

Register it in AuthServiceProvider:

protected $policies = [
    Post::class => PostPolicy::class,
];

Use the policy in a controller:

$this->authorize('update', $post);

This ensures secure and organized access control.