Laravel Pennant

You can define a feature flag using the Feature::define method. The definition accepts a unique name and a callback. The callback receives the current scope (typically a User instance) and should return a boolean indicating whether the feature is active for that scope.

use Laravel//Pennant//Feature;

Feature::define('new-dashboard', function (User $user) {
    return $user->isAdmin();
});

You can publish the Pennant configuration file and database migrations to your application using the following Artisan commands:

To publish the configuration file:

php artisan vendor:publish --tag=pennant-config

To publish the database migrations:

php artisan vendor:publish --tag=pennant-migrations

When implementing feature flags, be mindful of the following:

• Missing Scopes: Forgetting to scope features to specific users or entities when the feature logic depends on them.
• Naming Conventions: Not following existing naming conventions for feature flags within your application.

You can explicitly activate a feature flag using Feature::activate(). This can be done globally or scoped to a specific user or entity using Feature::for($scope)->activate().

// Global activation
Feature::activate('new-dashboard');

// Scoped activation
Feature::for($user)->activate('new-dashboard');

To check if a feature is active, use the Feature::active() method for global checks, or Feature::for($scope)->active() to check if a feature is active for a specific user or entity.

// Global check
if (Feature::active('new-dashboard')) {
    // Feature is active
}

// Scoped check (e.g., for a specific user)
if (Feature::for($user)->active('new-dashboard')) {
    // Feature is active for this user
}

Laravel Pennant provides a @feature Blade directive to conditionally render UI elements based on whether a feature flag is active. It supports an @else block for fallback content.

@feature('new-dashboard')
    <x-new-dashboard />
@else
    <x-old-dashboard />
@endfeature

When using the database driver for Pennant, you can customize the table name and the database connection used for your feature flags via your application's configuration. By default, the driver uses a table named features and the default database connection.

To customize these, add a configuration entry for your specific store under pennant.stores.{store_name} using the table and connection keys.

// Example configuration structure
'pennant' => [
    'stores' => [
        'my_custom_store' => [
            'table' => 'my_feature_flags',
            'connection' => 'mysql_secondary',
        ],
    ],
],

The EnsureFeaturesAreActive middleware ensures that a specific set of features are enabled for the current request. If any of the required features are inactive, the middleware will interrupt the request.

By default, if a feature is inactive, the middleware will abort(400) with an error message (if app.debug is enabled). However, you can customize the response behavior using the whenInactive method.

// In your routes file
Route::get('/premium-feature', function () {
    return 'Welcome to the premium area!';
})->middleware(EnsureFeaturesAreActive::using(Feature::Premium));

To manage memory or reset state during testing, you can clear resolved stores or flush driver caches.

• flushCache(): Tells all currently resolved stores to flush their internal caches.
• forgetDriver($name): Removes a specific store from the manager's internal cache.
• forgetDrivers(): Removes all resolved stores.

// Flush caches for all stores
Feature::flushCache();

// Forget a specific store
Feature::forgetDriver('database');

// Forget all stores
Feature::forgetDrivers();