feat: Identity overrides in local evaluation mode (#69)

* feat: Identity overrides in local evaluation mode

Author: khvn26

src/Engine/Environments/EnvironmentModel.php

@@ -6,7 +6,9 @@
 use Flagsmith\Concerns\JsonSerializer;
 use Flagsmith\Engine\Environments\Integrations\IntegrationModel;
 use Flagsmith\Engine\Projects\ProjectModel;
+use Flagsmith\Engine\Identities\IdentityModel;
 use Flagsmith\Engine\Utils\Collections\FeatureStateModelList;
+use Flagsmith\Engine\Utils\Collections\IdentityList;
 
 #[\AllowDynamicProperties]
 class EnvironmentModel
@@ -16,17 +18,11 @@ class EnvironmentModel
     public int $id;
     public string $api_key;
     public FeatureStateModelList $feature_states;
-    public IntegrationModel $segment_config;
-    public IntegrationModel $heap_config;
-    public IntegrationModel $mixpanel_config;
-    public IntegrationModel $amplitude_config;
+    public IdentityList $identity_overrides;
     public ProjectModel $project;
     private array $keys = [
+        'identity_overrides' => 'Flagsmith\Engine\Utils\Collections\IdentityList',
         'feature_states' => 'Flagsmith\Engine\Utils\Collections\FeatureStateModelList',
-        'segment_config' => 'Flagsmith\Engine\Environments\Integrations\IntegrationModel',
-        'heap_config' => 'Flagsmith\Engine\Environments\Integrations\IntegrationModel',
-        'mixpanel_config' => 'Flagsmith\Engine\Environments\Integrations\IntegrationModel',
-        'amplitude_config' => 'Flagsmith\Engine\Environments\Integrations\IntegrationModel',
         'project' => 'Flagsmith\Engine\Projects\ProjectModel',
     ];
 

src/Engine/Utils/Collections/IdentityList.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace Flagsmith\Engine\Utils\Collections;
+
+class IdentityList extends \ArrayObject implements \JsonSerializable
+{
+    use CollectionTrait;
+    private string $list_type = 'Flagsmith\Engine\Identities\IdentityModel';
+    /**
+     * store identity models by identifiers.
+     * @param mixed $key
+     * @param IdentityModel $value
+     * @return void
+     */
+    public function offsetSet($offset, $value): void
+    {
+        parent::offsetSet($value->identifier, $value);
+    }
+}

src/Flagsmith.php

@@ -327,7 +327,7 @@ public function getIdentitySegments(string $identifier, ?object $traits = null):
         }
 
         $traits = $traits ?? (object)[];
-        $identityModel = $this->buildIdentityModel($identifier, $traits);
+        $identityModel = $this->getIdentityModel($identifier, $traits);
         $segmentModels = SegmentEvaluator::getIdentitySegments($this->environment, $identityModel);
 
         return array_map(fn ($segment) => (new Segment())
@@ -384,7 +384,7 @@ private function getEnvironmentFlagsFromDocument(): Flags
      */
     private function getIdentityFlagsFromDocument(string $identifier, object $traits): Flags
     {
-        $identityModel = $this->buildIdentityModel($identifier, $traits);
+        $identityModel = $this->getIdentityModel($identifier, $traits);
         $featureStates = Engine::getIdentityFeatureStates($this->environment, $identityModel);
 
         return Flags::fromFeatureStateModels(
@@ -461,7 +461,7 @@ private function getIdentityFlagsFromApi(string $identifier, ?object $traits): F
      *
      * @throws FlagsmithClientError
      */
-    private function buildIdentityModel(string $identifier, ?object $traits): IdentityModel
+    private function getIdentityModel(string $identifier, ?object $traits): IdentityModel
     {
         if (empty($this->environment)) {
             throw new FlagsmithClientError('Unable to build identity model when no local environment present.');
@@ -474,10 +474,16 @@ private function buildIdentityModel(string $identifier, ?object $traits): Identi
                 ->withTraitValue($value);
         }
 
-        return (new IdentityModel())
-            ->withIdentifier($identifier)
-            ->withEnvironmentApiKey($this->apiKey)
-            ->withIdentityTraits(new IdentityTraitList($traitModels));
+        $identityModel = isset($this->environment->identity_overrides) ? $this->environment->identity_overrides[$identifier] ?? null : null;
+
+        if (is_null($identityModel)) {
+            return (new IdentityModel())
+                ->withIdentifier($identifier)
+                ->withEnvironmentApiKey($this->apiKey)
+                ->withIdentityTraits(new IdentityTraitList($traitModels));
+        }
+
+        return $identityModel->withIdentityTraits(new IdentityTraitList($traitModels));
     }
 
     /**

tests/Data/environment.json

@@ -52,5 +52,30 @@
       "segment_id": null,
       "enabled": true
     }
+  ],
+  "identity_overrides": [
+    {
+      "identifier": "overridden-id",
+      "identity_uuid": "0f21cde8-63c5-4e50-baca-87897fa6cd01",
+      "created_date": "2019-08-27T14:53:45.698555Z",
+      "updated_at": "2023-07-14 16:12:00.000000",
+      "environment_api_key": "B62qaMZNwfiqT76p38ggrQ",
+      "identity_features": [
+        {
+          "id": 1,
+          "feature": {
+            "id": 1,
+            "name": "some_feature",
+            "type": "STANDARD"
+          },
+          "featurestate_uuid": "1bddb9a5-7e59-42c6-9be9-625fa369749f",
+          "feature_state_value": "some-overridden-value",
+          "enabled": false,
+          "environment": 1,
+          "identity": null,
+          "feature_segment": null
+        }
+      ]
+    }
   ]
 }

tests/FlagsmithClientTest.php

@@ -279,4 +279,19 @@ public function testGetIdentitySegmentsWithValidTrait()
             $this->assertEquals($segments[0]->getName(), 'Test segment');
         }
     }
+
+    public function testLocalEvaluationGetIdentityOverride()
+    {
+        foreach (ClientFixtures::localEvalFlagsmith() as $flagsmith) {
+            $identifier = 'overridden-id';
+            $featureName = 'some_feature';
+
+            $identityFlags = $flagsmith->getIdentityFlags($identifier);
+
+            $flag = $identityFlags->getFlag($featureName);
+
+            $this->assertEquals($flag->enabled, false);
+            $this->assertEquals($flag->value, 'some-overridden-value');
+        }
+    }
 }