Improved processing the server response with errors (#14)

* Fixed throwing exception on invalid request

* Refactored exception message

Author: voskobovich

src/ResponseBuilder.php

@@ -9,7 +9,7 @@ class ResponseBuilder
     public function build(ResponseInterface $httpResponse)
     {
         $body = $httpResponse->getBody();
-        
+
         $normalizedResponse = $this->getNormalizedResponse($body);
 
         return new Response($normalizedResponse['data'], $normalizedResponse['errors']);
@@ -18,9 +18,11 @@ public function build(ResponseInterface $httpResponse)
     private function getNormalizedResponse(string $body)
     {
         $decodedResponse = $this->getJsonDecodedResponse($body);
-        
-        if (!array_key_exists('data', $decodedResponse)) {
-            throw new \UnexpectedValueException('Invalid GraphQL JSON response.');
+
+        if (false === array_key_exists('data', $decodedResponse) && empty($decodedResponse['errors'])) {
+            throw new \UnexpectedValueException(
+                'Invalid GraphQL JSON response. Response body: ' . json_encode($decodedResponse)
+            );
         }
 
         return [
@@ -35,8 +37,11 @@ private function getJsonDecodedResponse(string $body)
 
         $error = json_last_error();
         if (JSON_ERROR_NONE !== $error) {
-            throw new \UnexpectedValueException('Invalid JSON response.');
+            throw new \UnexpectedValueException(
+                'Invalid JSON response. Response body: ' . $body
+            );
         }
+
         return $response;
     }
 }

tests/ResponseBuilderTest.php

@@ -15,7 +15,7 @@ public function testBuildMalformedResponse()
             ->willReturn('malformed response');
 
         $this->expectException(\UnexpectedValueException::class);
-        $this->expectExceptionMessage('Invalid JSON response.');
+        $this->expectExceptionMessage('Invalid JSON response. Response body: ');
 
         $builder = new ResponseBuilder();
         $builder->build($mockHttpResponse);
@@ -45,7 +45,7 @@ public function testBuildInvalidGraphqlJsonResponse(string $body)
             ->willReturn($body);
 
         $this->expectException(\UnexpectedValueException::class);
-        $this->expectExceptionMessage('Invalid GraphQL JSON response.');
+        $this->expectExceptionMessage('Invalid GraphQL JSON response. Response body: ');
 
         $builder = new ResponseBuilder();
         $builder->build($mockHttpResponse);
@@ -68,13 +68,28 @@ public function testBuildValidGraphqlJsonWithoutErrors()
         );
     }
 
-    public function testBuildValidGraphqlJsonWithErrors()
+    public function buildValidGraphqlJsonWithErrorsProvider()
+    {
+        return [
+            'Response with null data' => [
+                'body' => '{"data": null, "errors": [{"foo": "bar"}]}',
+            ],
+            'Response without data' => [
+                'body' => '{"errors": [{"foo": "bar"}]}',
+            ],
+        ];
+    }
+
+    /**
+     * @dataProvider buildValidGraphqlJsonWithErrorsProvider
+     */
+    public function testBuildValidGraphqlJsonWithErrors(string $body)
     {
         $mockHttpResponse = $this->createMock(\Psr\Http\Message\ResponseInterface::class);
 
         $mockHttpResponse->expects($this->once())
             ->method('getBody')
-            ->willReturn('{"data": null, "errors": [{"foo": "bar"}]}');
+            ->willReturn($body);
 
         $builder = new ResponseBuilder();
         $response = $builder->build($mockHttpResponse);