FeatureFlagResolver.php

<?php
namespace App\FeatureFlag\Resolver;

use Symfony\Component\DependencyInjection\Attribute\AutoconfigureTag;

// In order to tag all classes that implements this interface
#[AutoconfigureTag()]
interface FeatureFlagResolverInterface
{
    public function isEnabled(string $name): bool;
    public function supports(string $name): bool;
}

// fetch the feature flag in database
final class DatabaseFeatureFlagResolver implements FeatureFlagResolverInterface
{
    public function __construct(private readonly FeatureFlagRepository $featureFlagRepository) {}

    public function isEnabled(string $name): bool
    {
        return $this->featureFlagRepository->getByName($name)->isEnabled();
    }

    public function supports(string $name): bool
    {
        // Does the feature is in the configuration Database source?
        return \in_array($name, DatabaseStorageFeatureFlagEnum::names());
    }
}

// fetch the feature flag in Symfony parameter
final class ParameterFeatureFlagResolver implements FeatureFlagResolverInterface
{
    public function __construct(private readonly ParameterBagInterface $parameterBag){}

    public function isEnabled(string $name): bool
    {
        return $this->parameterBag->get($name);
    }

    public function supports(string $name): bool
    {
        // Does the feature is in the configuration Parameter source?
        return \in_array($name, ParameterFeatureFlagEnum::names());
    }
}

// return the feature flag depending a period
final class PeriodFeatureFlagResolver implements FeatureFlagResolverInterface
{
    public function isEnabled(string $name): bool
    {
        $now = new \DateTime();
        return $now > new \DateTime("24-07-2023 23:00")
            && $now < new \DateTime("25-07-2023 08:00");
    }


    public function supports(string $name): bool
    {
        // Does the feature is in the configuration Period source?
        return \in_array($name, PeriodFeatureFlagEnum::names(), 1);
    }
}

// return the feature flag with random true/false to simulate A/B testing
final class ABTestingFeatureFlagResolver implements FeatureFlagResolverInterface
{
    public function isEnabled(string $name): bool
    {
        return random_int(0, 1);
    }

    public function supports(string $name): bool
    {
        // Does the feature is in the configuration A/B testing source?
        return \in_array($name, ABTestingFeatureFlagEnum::names());
    }
}