Added possibility to only load relationship data when the relationshi…

…p itself is included
woohoolabs · Nov 24, 2015 · 6c8f328 · 6c8f328
1 parent b0e5827
commit 6c8f328
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Showing 7 changed files with 76 additions and 11 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -3,10 +3,12 @@
 ADDED:
 
 - Possibility to pass additional meta information for documents when fetching the response
+- Possibility to only load relationship data when the relationship itself is included
 
 CHANGED:
 
 - Renamed `getDefaultRelationships()` to `getDefaultIncludedRelationships()` in transformers to better reflect its meaning
+- The "data" key of relationships won't be present in the response when it is empty
 
 REMOVED:
 

diff --git a/README.md b/README.md
@@ -27,6 +27,7 @@ manifestation of our vision.
     * [Exceptions](#exceptions)
     * [JsonApi class](#jsonapi-class)
 * [Advanced Usage](#advanced-usage)
+    * [Loading relationship data efficiently](#loading-relationship-data-efficiently)
     * [Content negotiation](#content-negotiation)
     * [Request/response validation](#request-response-validation)
     * [Middlewares](#middlewares)
@@ -677,6 +678,8 @@ functionality of Woohoo Labs. Yin, it is highly recommended to utilize this clas
 
 This section guides you through the advanced features of Yin.
 
+#### Loading relationship data efficiently
+
 #### Content negotiation
 
 #### Request/response validation

diff --git a/examples/User/JsonApi/Resource/UserResourceTransformer.php b/examples/User/JsonApi/Resource/UserResourceTransformer.php
@@ -118,7 +118,10 @@ public function getRelationships($user)
             "contacts" => function(array $user) {
                 return
                     ToManyRelationship::create()
-                        ->setData($user["contacts"], $this->contactTransformer)
+                        ->setDataAsCallable(function() use ($user) {
+                            return $user["contacts"];
+                        }, $this->contactTransformer)
+                        ->omitWhenNotIncluded()
                     ;
             }
         ];

diff --git a/src/JsonApi/Schema/Relationship/AbstractRelationship.php b/src/JsonApi/Schema/Relationship/AbstractRelationship.php
@@ -15,7 +15,17 @@ abstract class AbstractRelationship
     /**
      * @var mixed
      */
-    protected $data;
+    private $data;
+
+    /**
+     * @var bool
+     */
+    protected $isCallableData;
+
+    /**
+     * @var bool
+     */
+    protected $omitDataWhenNotIncluded;
 
     /**
      * @var \WoohooLabs\Yin\JsonApi\Transformer\ResourceTransformerInterface
@@ -49,6 +59,8 @@ public function __construct(
         $this->meta = $meta;
         $this->links = $links;
         $this->data = $data;
+        $this->isCallableData = false;
+        $this->omitDataWhenNotIncluded = false;
         $this->resourceTransformer = $resourceTransformer;
     }
 
@@ -60,11 +72,33 @@ public function __construct(
     public function setData($data, ResourceTransformerInterface $resourceTransformer)
     {
         $this->data = $data;
+        $this->isCallableData = false;
         $this->resourceTransformer = $resourceTransformer;
 
         return $this;
     }
 
+    /**
+     * @param mixed $data
+     * @param \WoohooLabs\Yin\JsonApi\Transformer\ResourceTransformerInterface $resourceTransformer
+     * @return $this
+     */
+    public function setDataAsCallable(callable $data, ResourceTransformerInterface $resourceTransformer)
+    {
+        $this->data = $data;
+        $this->isCallableData = true;
+        $this->resourceTransformer = $resourceTransformer;
+
+        return $this;
+    }
+
+    public function omitWhenNotIncluded()
+    {
+        $this->omitDataWhenNotIncluded = true;
+
+        return $this;
+    }
+
     /**
      * @param \WoohooLabs\Yin\JsonApi\Transformer\Transformation $transformation
      * @param string $resourceType
@@ -81,7 +115,18 @@ public function transform(
         array $additionalMeta = []
     ) {
         $relationship = null;
-        $transformedData = $this->transformData($transformation, $relationshipName, $defaultRelationships);
+
+        if ($this->omitDataWhenNotIncluded === false ||
+            $transformation->request->isIncludedRelationship(
+                $transformation->basePath,
+                $relationshipName,
+                $defaultRelationships
+            )
+        ) {
+            $transformedData = $this->transformData($transformation, $relationshipName, $defaultRelationships);
+        } else {
+            $transformedData = null;
+        }
 
         if ($transformation->request->isIncludedField($resourceType, $relationshipName)) {
             $relationship = [];
@@ -98,7 +143,9 @@ public function transform(
             }
 
             // DATA
-            $relationship["data"] = $transformedData;
+            if (isset($transformedData) === true) {
+                $relationship["data"] = $transformedData;
+            }
         }
 
         return $relationship;
@@ -129,4 +176,12 @@ protected function transformResource(
 
         return $this->resourceTransformer->transformToResourceIdentifier($domainObject);
     }
+
+    /**
+     * @return mixed
+     */
+    protected function retrieveData()
+    {
+        return $this->isCallableData ? call_user_func($this->data, $this) : $this->data;
+    }
 }
diff --git a/src/JsonApi/Schema/Relationship/ToManyRelationship.php b/src/JsonApi/Schema/Relationship/ToManyRelationship.php
@@ -32,12 +32,13 @@ protected function transformData(
         $relationshipName,
         array $defaultRelationships
     ) {
-        if (empty($this->data) || $this->resourceTransformer === null) {
-            return [];
+        $data = $this->retrieveData();
+        if (empty($data) || $this->resourceTransformer === null) {
+            return null;
         }
 
         $content = [];
-        foreach ($this->data as $item) {
+        foreach ($data as $item) {
             $content[] = $this->transformResource($transformation, $item, $relationshipName, $defaultRelationships);
         }
 

diff --git a/src/JsonApi/Schema/Relationship/ToOneRelationship.php b/src/JsonApi/Schema/Relationship/ToOneRelationship.php
@@ -32,13 +32,14 @@ protected function transformData(
         $relationshipName,
         array $defaultRelationships
     ) {
-        if ($this->data === null || $this->resourceTransformer === null) {
+        $data = $this->retrieveData();
+        if (isset($data) === false || $this->resourceTransformer === null) {
             return null;
         }
 
         return $this->transformResource(
             $transformation,
-            $this->data,
+            $data,
             $relationshipName,
             $defaultRelationships
         );

diff --git a/tests/JsonApi/Transformer/AbstractResourceTransformerTest.php b/tests/JsonApi/Transformer/AbstractResourceTransformerTest.php
@@ -135,7 +135,7 @@ public function testTransformToResourceWithDefaultRelationship()
                 $this->assertInstanceOf(RequestInterface::class, $request);
 
                 $relationship = new ToOneRelationship();
-                $relationship->setData([], new StubResourceTransformer("user", "2"));
+                $relationship->setData(["Father Vader"], new StubResourceTransformer("user", "2"));
                 return $relationship;
             }
         ];
@@ -208,7 +208,7 @@ public function testTransformToRelationship()
         $relationships = [
             "father" => function () {
                 $relationship = new ToOneRelationship();
-                $relationship->setData([], new StubResourceTransformer("user", "2"));
+                $relationship->setData(["Father Vader"], new StubResourceTransformer("user", "2"));
                 return $relationship;
             }
         ];