Added support for new GetLeftRelations protocol buffer method.

From a remote model, treated as a right-hand entity, it is now possible to query back to retrieve a list of owning left-hand models

protobuf/Relationship/RelationshipServiceClient.php

@@ -49,6 +49,20 @@ public function GetRelations(\Relationship\RelationshipLeftEntity $argument,
       $metadata, $options);
     }
 
+    /**
+     * Get the dominant left hand entity from a right hand entity.
+     * @param \Relationship\RelationshipRightEntity $argument input argument
+     * @param array $metadata metadata
+     * @param array $options call options
+     */
+    public function GetLeftRelations(\Relationship\RelationshipRightEntity $argument,
+      $metadata = [], $options = []) {
+      return $this->_serverStreamRequest('/relationship.RelationshipService/GetLeftRelations',
+      $argument,
+      ['\Relationship\Relationship', 'decode'],
+      $metadata, $options);
+    }
+
     /**
      * Update an existing relationship.
      * @param \Relationship\UpdateRelationshipRequest $argument input argument

src/Builder.php

@@ -13,6 +13,7 @@
 use LushDigital\MicroServiceRemoteModels\Traits\TimeoutTrait;
 use Psr\Http\Message\ResponseInterface;
 use Relationship\RelationshipLeftEntity;
+use Relationship\RelationshipRightEntity;
 use Relationship\RelationshipServiceClient;
 
 /**
@@ -533,4 +534,35 @@ protected function getGrpcPort()
     {
         return !empty(getenv('REMOTE_MODEL_GRPC_PORT')) ? getenv('REMOTE_MODEL_GRPC_PORT') : 50051;
     }
+
+    /**
+     * Get a list of all remote models that own the current model.
+     *
+     * @param string $ownerModel
+     *     Fully qualified class name for the owner model.
+     *
+     * @return Model[]
+     */
+    public function getOwners($ownerModel)
+    {
+        $rightEntity = new RelationshipRightEntity;
+        $rightEntity->setRightId($this->model->getPrimaryKeyValue());
+
+        // Get all related IDs for this model.
+        $call = $this->getRelationshipClient((new $ownerModel), $this->getModel())
+            ->GetLeftRelations($rightEntity, [], ['timeout' => $this->getTimeoutVal(10)]);
+        $owners = $call->responses();
+
+        $ownerInstances = [];
+
+        // Detach each relation instance that we find.
+        foreach ($owners as $index => $owner) {
+            $ownerInstance = new $ownerModel;
+            $ownerInstance->setPrimaryKeyValue($owner->getLeftId());
+
+            $ownerInstances[] = $ownerInstance;
+        }
+
+        return $ownerInstances;
+    }
 }

src/Model.php

@@ -590,4 +590,16 @@ public function getSavePromise()
             ]);
         }
     }
+
+    /**
+     * Get a list of all remote models that own this one.
+     *
+     * @param string $ownerModel
+     *     Fully qualified class name for the owner model.
+     * @return Model[]
+     */
+    public function getOwners($ownerModel)
+    {
+        return $this->newQueryBuilder()->getOwners($ownerModel);
+    }
 }