README

Implement feature flags within your Laravel application using ConfigCat cloud service.

Installation

You can install the package via composer:

composer require pod-point/laravel-configcat

For Laravel 5.4 up to 9.x

composer require pod-point/laravel-configcat:^3.0

Publishing the config file

Next, you should publish the Laravel package configuration file using the vendor:publish Artisan command. It will be placed in your application's config directory:

php artisan vendor:publish --provider="PodPoint\ConfigCat\ConfigCatServiceProvider"

Don't forget to specify your ConfigCat SDK key within the freshly published Laravel configuration file under config/configcat.php.

The Laravel configuration for this package comes with sensible defaults. See config/configcat.php for more details.

Usage

Facade & global helper

The ConfigCat facade as well as the global helper can be used to retrieve the actual value of the feature flag, text or number setting:

use PodPoint\ConfigCat\Facades\ConfigCat;

$flag = ConfigCat::get('new_registration_flow');

$flag = configcat('new_registration_flow');

Note: You can define the actual value of a feature flag to be bool(true) or bool(false) on ConfigCat but not only, it can also be a number or a text setting.

If the feature flag is undefined or something went wrong, bool(false) will be returned by default, however you can change this by specifying a default value only when using the Facade or the global helper to retrieve the feature flag value using:

use PodPoint\ConfigCat\Facades\ConfigCat;

$flag = ConfigCat::get('new_registration_flow', true);

$flag = configcat('new_registration_flow', true);

You can also globally sepcify a default value from the config/configcat.php file.

⚠️ Only boolean, string, integer or float default value types are supported as these are the only setting types available from ConfigCat.

Validation rule

Given the following validation rules:

Validator::make([
    'email' => 'taylor@laravel.com',
    'username' => 'taylor',
], [
    'email' => 'required_if_configcat:new_registration_flow,true',
    'username' => 'required_if_configcat:new_registration_flow,false',
]);

• When the feature flag is on
  • The email will be a required field
  • The username will be an optional field
• When the feature flag is off, undefined, a text or number setting
  • The email will be an optional field
  • The username will be a required field

HTTP middleware

The following route will only be accessible if the feature flag is truthy, otherwise a 404 will be thrown.

Router::get('/registration')->middleware('configcat.on:new_registration_flow');

The opposite is possible, also throwing a 404 if the feature flag is falsy:

Router::get('/sign-up')->middleware('configcat.off:new_registration_flow');

Note: undefined, text or number settings will be considered as feature flags turned off.

Blade directive

The following view content will only be rendered if the feature flag is truthy:

@configcat('new_registration_flow')
    New registration form
@endconfigcat

@unlessconfigcat('new_registration_flow')
    Old registration form
@endconfigcat

@configcat('new_registration_flow_1')
    Sign up
@elseconfigcat('new_registration_flow_2')
    Get started
@else
    Register
@endconfigcat

Note: undefined, text or number settings will be considered as feature flags turned off.

Advanced usage

User targeting

The User Object is essential if you'd like to use ConfigCat's Targeting feature.

ConfigCat needs to understand the representation of your users from your application. To do so, you will need to transform your user into a ConfigCat\User object. This can be done directly from the config/configcat.php file. Here is an example:

'user' => \PodPoint\ConfigCat\Support\DefaultUserTransformer::class,

Which will be using a sensible default transformer:

class DefaultUserTransformer
{
    public function __invoke(\Illuminate\Foundation\Auth\User $user)
    {
        return new \ConfigCat\User($user->getKey(), $user->email);
    }
}

Feel free to create your own transformer class and use it instead, just remember that it needs to be callable with the __invoke() function.

Note: for security reasons, all of the logic computation for the user targeting is executed on your application side of things using ConfigCat's SDK. No user details will be leaving your application in order find out wether or not a user should have a feature flag enabled or not.

Once you have defined your mapping, you will be able to explicitly use the representation of your user when checking a feature flag:

use App\Models\User;
use PodPoint\ConfigCat\Facades\ConfigCat;

$user = User::where('email', 'taylor@laravel.com')->firstOrFail();
ConfigCat::get('new_registration_flow', $default, $user);

This is also applicable for the global helper and the Blade directive:

configcat('new_registration_flow', $default, $user);

@configcat('new_registration_flow', $user)
    New registration form
@endconfigcat

Note: if you have defined your user mapping but are not explicitly using a specific user when checking for a flag, we will automatically try to use the logged in user, if any, for convenience.

Caching & logging

This package supports native Laravel caching and logging capabilities in order to cache the feature flag values from ConfigCat's CDN as well as log any information when resolving feature flags. We've setup some sensible defaults but various levels of caching and logging can be configured.

See config/configcat.php for more info.

Test support: mock, fake & overrides

In-memory testing

When writing unit or functional tests, you may need to be able to mock or fake this package completely so you can test various behaviors within your application. This is all possible through the powerful Facade.

Mocking:

use PodPoint\ConfigCat\Facades\ConfigCat;

ConfigCat::shouldReceive('get')
    ->once()
    ->with('new_registration_flow')
    ->andReturn(true);

See https://laravel.com/docs/mocking#mocking-facades for more info.

Fake:

Faking it will prevent the package to genuinely try to hit ConfigCat's CDN:

use PodPoint\ConfigCat\Facades\ConfigCat;

// you can fake it
ConfigCat::fake();
// optionally setup some predefined feature flags for your test
ConfigCat::fake(['new_registration_flow' => true]);

End-to-end testing

When running tests within a browser which doesn't share the same instance of the application, using mocks or fakes is not applicable. This is why we provide some overrides through ConfigCat SDK which will make the client under the hood localhost only and will use a locally generated json file in order to read the feature flags for the system under test.

First of all, you will need to make sure to enable overrides from config/configcat.php. You could also optionally tweak the file path for the json file if you wish to. The file will be automatically created for you when using overrides.

Similarly to ConfigCat::fake() you can come up with some predefined feature flags which will be saved into a json file:

use PodPoint\ConfigCat\Facades\ConfigCat;

ConfigCat::override(['new_registration_flow' => true]);

Testing

Run the tests with:

composer test

Changelog

Please see our Releases for more information on what has changed recently.

Contributing

Please see CONTRIBUTING for details.

Credits

• configcat/php-sdk
• ylsideas/feature-flags for inspiration
• Pod Point
• All Contributors

License

The MIT License (MIT). Please see License File for more information.

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