feat(php): Enable FFE tests and add /ffe endpoints

manifests/php.yml

@@ -483,8 +483,7 @@ manifest:
     - declaration: missing_feature (Not implemented yet)
       component_version: <1.12.0
   tests/docker_ssi/test_docker_ssi_appsec.py::TestDockerSSIAppsecFeatures::test_telemetry_source_ssi: missing_feature
-  tests/ffe/test_dynamic_evaluation.py: missing_feature
-  tests/ffe/test_exposures.py: missing_feature
+  tests/ffe/test_exposures.py::Test_FFE_Exposure_Caching_Same_Subject::test_ffe_exposure_caching_same_subject: missing_feature (PHP shared-nothing architecture - exposure cache does not persist across HTTP requests)
   tests/integrations/crossed_integrations/test_kafka.py::Test_Kafka: missing_feature
   tests/integrations/crossed_integrations/test_kinesis.py::Test_Kinesis_PROPAGATION_VIA_MESSAGE_ATTRIBUTES: missing_feature
   tests/integrations/crossed_integrations/test_rabbitmq.py::Test_RabbitMQ_Trace_Context_Propagation: missing_feature
@@ -543,7 +542,6 @@ manifest:
   tests/parametric/test_dynamic_configuration.py::TestDynamicConfigV1_EmptyServiceTargets: v1.4.0
   tests/parametric/test_dynamic_configuration.py::TestDynamicConfigV1_ServiceTargets: missing_feature
   tests/parametric/test_dynamic_configuration.py::TestDynamicConfigV2: missing_feature
-  tests/parametric/test_ffe/test_dynamic_evaluation.py::Test_Feature_Flag_Dynamic_Evaluation: missing_feature
   tests/parametric/test_headers_b3.py::Test_Headers_B3::test_headers_b3_migrated_extract_invalid: missing_feature (Need to remove b3=b3multi alias)
   tests/parametric/test_headers_b3.py::Test_Headers_B3::test_headers_b3_migrated_extract_valid: missing_feature (Need to remove b3=b3multi alias)
   tests/parametric/test_headers_b3.py::Test_Headers_B3::test_headers_b3_migrated_inject_valid: missing_feature (Need to remove b3=b3multi alias)

utils/build/docker/php/apache-mod/php.conf

@@ -27,6 +27,7 @@
         RewriteRule "^/load_dependency$" "/load_dependency/"
         RewriteRule "^/signup$" "/signup/"
         RewriteRule "^/shell_execution$" "/shell_execution/"
+        RewriteRule "^/ffe$" "/ffe.php" [L]
         RewriteCond /var/www/html/%{REQUEST_URI} !-f
         RewriteRule "^/rasp/(.*)" "/rasp/$1.php" [L]
         RewriteRule "^/api_security.sampling/.*" "/api_security_sampling.php$0" [L]

utils/build/docker/php/common/ffe.php

@@ -0,0 +1,53 @@
+<?php
+
+header('Content-Type: application/json');
+
+$input = json_decode(file_get_contents('php://input'), true);
+
+if (!is_array($input)) {
+    http_response_code(400);
+    echo json_encode(['error' => 'Invalid JSON body']);
+    exit;
+}
+
+$flag = isset($input['flag']) ? $input['flag'] : null;
+$variationType = isset($input['variationType']) ? $input['variationType'] : null;
+$defaultValue = isset($input['defaultValue']) ? $input['defaultValue'] : null;
+$targetingKey = array_key_exists('targetingKey', $input) ? $input['targetingKey'] : '';
+$attributes = isset($input['attributes']) ? $input['attributes'] : [];
+
+try {
+    // Use OpenFeature API if available, fall back to direct provider
+    if (class_exists('\OpenFeature\API')) {
+        $provider = new \DDTrace\OpenFeature\DataDogProvider();
+        \OpenFeature\API::setProvider($provider);
+        $client = \OpenFeature\API::getClient();
+
+        $context = new \OpenFeature\implementation\flags\EvaluationContext(
+            $targetingKey,
+            new \OpenFeature\implementation\flags\Attributes($attributes)
+        );
+
+        $value = match ($variationType) {
+            'BOOLEAN' => $client->getBooleanValue($flag, (bool) $defaultValue, $context),
+            'STRING' => $client->getStringValue($flag, (string) $defaultValue, $context),
+            'INTEGER' => $client->getIntegerValue($flag, (int) $defaultValue, $context),
+            'NUMERIC' => $client->getFloatValue($flag, (float) $defaultValue, $context),
+            'JSON' => $client->getObjectValue($flag, is_array($defaultValue) ? $defaultValue : [], $context),
+            default => $defaultValue,
+        };
+    } else {
+        // Fallback to direct provider (no OpenFeature SDK installed)
+        $provider = \DDTrace\FeatureFlags\Provider::getInstance();
+        $provider->start();
+        $result = $provider->evaluate($flag, $variationType, $defaultValue, $targetingKey, $attributes);
+        $value = $result['value'];
+    }
+
+    // Flush exposure events immediately for system test observability
+    \DDTrace\FeatureFlags\Provider::getInstance()->flush();
+
+    echo json_encode(['value' => $value]);
+} catch (\Throwable $e) {
+    echo json_encode(['value' => $defaultValue, 'error' => $e->getMessage()]);
+}

utils/build/docker/php/parametric/composer.json

@@ -7,7 +7,8 @@
     "amphp/log": "2.x-dev",
     "open-telemetry/sdk": "^1.0.0",
     "symfony/http-client": "6.4.x-dev",
-    "nyholm/psr7": "^1.8@dev"
+    "nyholm/psr7": "^1.8@dev",
+    "open-feature/sdk": "^2.0"
   },
   "config": {
     "allow-plugins": {

utils/build/docker/php/parametric/server.php

@@ -546,6 +546,51 @@ function remappedSpanKind($spanKind) {
     return jsonResponse([]);
 }));
 
+// FFE (Feature Flags & Experimentation) endpoints
+$openFeatureClient = null;
+
+$router->addRoute('POST', '/ffe/start', new ClosureRequestHandler(function (Request $req) use (&$openFeatureClient) {
+    try {
+        $provider = new \DDTrace\OpenFeature\DataDogProvider();
+        \OpenFeature\API::setProvider($provider);
+        $openFeatureClient = \OpenFeature\API::getClient();
+        return jsonResponse([]);
+    } catch (\Throwable $e) {
+        return new Response(status: 500, body: json_encode(['error' => $e->getMessage()]));
+    }
+}));
+
+$router->addRoute('POST', '/ffe/evaluate', new ClosureRequestHandler(function (Request $req) use (&$openFeatureClient) {
+    try {
+        if ($openFeatureClient === null) {
+            $provider = new \DDTrace\OpenFeature\DataDogProvider();
+            \OpenFeature\API::setProvider($provider);
+            $openFeatureClient = \OpenFeature\API::getClient();
+        }
+
+        $flag = arg($req, 'flag');
+        $variationType = arg($req, 'variationType');
+        $defaultValue = arg($req, 'defaultValue');
+        $targetingKey = arg($req, 'targetingKey');
+        $attributes = arg($req, 'attributes') ?? [];
+
+        $context = new \OpenFeature\implementation\flags\EvaluationContext($targetingKey, new \OpenFeature\implementation\flags\Attributes($attributes));
+
+        $value = match ($variationType) {
+            'BOOLEAN' => $openFeatureClient->getBooleanValue($flag, (bool) $defaultValue, $context),
+            'STRING' => $openFeatureClient->getStringValue($flag, (string) $defaultValue, $context),
+            'INTEGER' => $openFeatureClient->getIntegerValue($flag, (int) $defaultValue, $context),
+            'NUMERIC' => $openFeatureClient->getFloatValue($flag, (float) $defaultValue, $context),
+            'JSON' => $openFeatureClient->getObjectValue($flag, is_array($defaultValue) ? $defaultValue : [], $context),
+            default => $defaultValue,
+        };
+
+        return jsonResponse(['value' => $value]);
+    } catch (\Throwable $e) {
+        return new Response(status: 500, body: json_encode(['error' => $e->getMessage()]));
+    }
+}));
+
 $middleware = new class implements Middleware {
     public function handleRequest(Request $request, RequestHandler $next): Response {
         $response = $next->handleRequest($request);