feat: add support for OpenFeature driver

README.md

@@ -48,6 +48,30 @@ enum FeatureFlag: string implements \Worksome\FeatureFlags\Contracts\FeatureFlag
 @endfeature
 ```
 
+### OpenFeature
+
+The `open_feature` driver adds support for [OpenFeature](https://openfeature.dev), a vendor-agnostic ecosystem for feature flagging.
+
+To use this, follow the steps below:
+
+1. Install an [OpenFeature provider](https://openfeature.dev/ecosystem?instant_search%5BrefinementList%5D%5Btype%5D%5B0%5D=Provider&instant_search%5BrefinementList%5D%5BallTechnologies%5D%5B0%5D=PHP)
+    ```shell
+    composer require open-feature/flagd-provider
+    ```
+2. Create or use [an existing OpenFeature resolver](src/Providers/OpenFeature/Resolvers)
+3. Add the required configuration to the configuration file
+    ```php
+    'open_feature' => [
+        'resolver' => \Worksome\FeatureFlags\Providers\OpenFeature\Resolvers\FlagdOpenFeatureResolver::class,
+        'options' => [
+            'protocol' => env('FLAGD_PROTOCOL'),
+            'host' => env('FLAGD_HOST'),
+            'port' => env('FLAGD_PORT'),
+            'secure' => env('FLAGD_SECURE'),
+        ],
+    ],
+    ```
+
 ## Changelog
 
 Please see the [Releases](https://github.com/worksome/feature-flags/releases) for more information on what has changed recently.

composer.json

@@ -13,15 +13,20 @@
         "guzzlehttp/guzzle": "^7.8",
         "illuminate/contracts": "^11.0 || ^12.0",
         "launchdarkly/server-sdk": "^6.4",
+        "open-feature/sdk": "^2.0",
         "spatie/laravel-package-tools": "^1.19"
     },
     "require-dev": {
         "nunomaduro/collision": "^8.6",
+        "open-feature/flagd-provider": "^1.0",
         "orchestra/testbench": "^9.12 || ^10.1",
         "pestphp/pest": "^3.7",
         "pestphp/pest-plugin-laravel": "^3.1",
         "worksome/coding-style": "^3.2"
     },
+    "suggest": {
+        "open-feature/flagd-provider": "Required to use the OpenFeature Flagd provider."
+    },
     "autoload": {
         "psr-4": {
             "Worksome\\FeatureFlags\\": "src"

config/feature-flags.php

@@ -37,6 +37,12 @@
              */
             'access-token' => env('FEATURE_FLAGS_API_ACCESS_TOKEN', null),
         ],
+        'open_feature' => [
+            'resolver' => env('OPEN_FEATURE_RESOLVER'),
+            'options' => [
+                // ...
+            ],
+        ],
     ],
 
     /**

src/FeatureFlagsManager.php

@@ -9,6 +9,8 @@
 use Worksome\FeatureFlags\Providers\Bucket\BucketProvider;
 use Worksome\FeatureFlags\Providers\FakeProvider;
 use Worksome\FeatureFlags\Providers\LaunchDarkly\LaunchDarklyProvider;
+use Worksome\FeatureFlags\Providers\OpenFeature\Contracts\OpenFeatureResolver;
+use Worksome\FeatureFlags\Providers\OpenFeature\OpenFeatureProvider;
 
 class FeatureFlagsManager extends Manager
 {
@@ -38,6 +40,19 @@ public function createLaunchDarklyDriver(): LaunchDarklyProvider
         );
     }
 
+    public function createOpenFeatureDriver(): OpenFeatureProvider
+    {
+        /** @var array{resolver: class-string<OpenFeatureResolver>|null, options: array<string, mixed>} $config */
+        $config = $this->config->get('feature-flags.providers.open_feature');
+        /** @var LoggerInterface $logger */
+        $logger = $this->getContainer()->get(LoggerInterface::class);
+
+        return new OpenFeatureProvider(
+            $config,
+            $logger,
+        );
+    }
+
     public function createFakeDriver(): FakeProvider
     {
         return new FakeProvider();

src/Providers/OpenFeature/Contracts/OpenFeatureResolver.php

@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Worksome\FeatureFlags\Providers\OpenFeature\Contracts;
+
+use OpenFeature\interfaces\provider\Provider;
+
+interface OpenFeatureResolver
+{
+    public function __invoke(array $options): Provider;
+}

src/Providers/OpenFeature/OpenFeatureProvider.php

@@ -0,0 +1,76 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Worksome\FeatureFlags\Providers\OpenFeature;
+
+use OpenFeature\implementation\flags\Attributes;
+use OpenFeature\implementation\flags\EvaluationContext;
+use OpenFeature\interfaces\flags\EvaluationContext as EvaluationContextContract;
+use OpenFeature\OpenFeatureAPI;
+use Psr\Log\LoggerInterface;
+use RuntimeException;
+use Worksome\FeatureFlags\Contracts\FeatureFlagEnum;
+use Worksome\FeatureFlags\Contracts\FeatureFlagsProvider;
+use Worksome\FeatureFlags\FeatureFlagUser;
+use Worksome\FeatureFlags\Providers\OpenFeature\Contracts\OpenFeatureResolver;
+
+class OpenFeatureProvider implements FeatureFlagsProvider
+{
+    private EvaluationContextContract|null $context = null;
+
+    /** @param array{resolver: class-string<OpenFeatureResolver>|null, options: array<string, mixed>} $config */
+    public function __construct(public readonly array $config, public readonly LoggerInterface $logger)
+    {
+    }
+
+    public function setUser(FeatureFlagUser $user): void
+    {
+        $id = (string) $user->id;
+
+        $this->context = new EvaluationContext(
+            targetingKey: $id,
+            attributes: new Attributes(['email' => $user->email, ... $user->custom]), // @phpstan-ignore argument.type
+        );
+    }
+
+    public function setAnonymousUser(): void
+    {
+        $this->context = new EvaluationContext(
+            targetingKey: 'anonymous',
+        );
+    }
+
+    public function flag(FeatureFlagEnum $flag): bool
+    {
+        assert(is_string($flag->value)); // @phpstan-ignore function.alreadyNarrowedType, function.alreadyNarrowedType
+
+        $resolver = $this->config['resolver'] ?? null;
+
+        if ($resolver === null) {
+            throw new RuntimeException('The `open_feature` driver requires a resolver.');
+        }
+
+        // @phpstan-ignore larastanStrictRules.noGlobalLaravelFunction
+        $provider = app($resolver);
+
+        if (! $provider instanceof OpenFeatureResolver) {
+            return false;
+        }
+
+        if ($this->context === null) {
+            $this->setAnonymousUser();
+        }
+
+        assert($this->context !== null);
+
+        $openFeature = OpenFeatureAPI::getInstance();
+
+        $openFeature->setProvider($provider($this->config['options']));
+
+        $openFeature->setLogger($this->logger);
+
+        // @phpstan-ignore arguments.count
+        return (bool) $openFeature->getClient()->getBooleanValue($flag->value, false, context: $this->context);
+    }
+}

src/Providers/OpenFeature/Resolvers/FlagdOpenFeatureResolver.php

@@ -0,0 +1,45 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Worksome\FeatureFlags\Providers\OpenFeature\Resolvers;
+
+use Illuminate\Support\Arr;
+use OpenFeature\interfaces\provider\Provider;
+use OpenFeature\Providers\Flagd\FlagdProvider;
+use Psr\Http\Client\ClientInterface;
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\StreamFactoryInterface;
+use RuntimeException;
+use Worksome\FeatureFlags\Providers\OpenFeature\Contracts\OpenFeatureResolver;
+
+/** @link https://packagist.org/packages/open-feature/flagd-provider */
+readonly class FlagdOpenFeatureResolver implements OpenFeatureResolver
+{
+    public function __construct(
+        private ClientInterface $client,
+        private RequestFactoryInterface $requestFactory,
+        private StreamFactoryInterface $streamFactory,
+    ) {
+    }
+
+    /** @param array{protocol?: string, host?: string, port?: int|numeric-string, secure?: bool} $options */
+    public function __invoke(array $options): Provider
+    {
+        if (! class_exists(FlagdProvider::class)) {
+            throw new RuntimeException('The `open-feature/flagd-provider` package is required.');
+        }
+
+        return new FlagdProvider([
+            'protocol' => Arr::get($options, 'protocol', 'tcp'),
+            'host' => Arr::get($options, 'host', 'localhost'),
+            'port' => Arr::get($options, 'port', 8013),
+            'secure' => Arr::get($options, 'secure', true),
+            'http' => [
+                'client' => $this->client,
+                'requestFactory' => $this->requestFactory,
+                'streamFactory' => $this->streamFactory,
+            ],
+        ]);
+    }
+}