diff --git a/google_vision.services.yml b/google_vision.services.yml
index f165465..3e2457c 100755
--- a/google_vision.services.yml
+++ b/google_vision.services.yml
@@ -1,7 +1,7 @@
 services:
   google_vision.api:
     class: Drupal\google_vision\GoogleVisionAPI
-    arguments: ['@config.factory']
+    arguments: ['@config.factory', '@http_client']
   google_vision.connector:
     class: Drupal\google_vision\Connector
     arguments: ['@google_vision.api']
diff --git a/src/Connector.php b/src/Connector.php
index 28aaae2..69c6170 100755
--- a/src/Connector.php
+++ b/src/Connector.php
@@ -1,9 +1,5 @@
 <?php
 
-/**
- * Google vision connector.
- */
-
 namespace Drupal\google_vision;
 
 use Drupal\Component\Serialization\Json;
@@ -16,108 +12,108 @@ use Symfony\Component\HttpFoundation\Response;
 class Connector extends ControllerBase {
 
   /**
-   * @var \Drupal\google_vision
+   * @var \Drupal\google_vision\GoogleVisionAPI
    */
-  protected $request;
+  protected $googleVisionAPI;
 
   /**
-   * Constructor.
+   * Constructs a Connector object.
    *
-   * @param \Drupal\google_vision\GoogleVisionAPI $image_Request.
+   * @param \Drupal\google_vision\GoogleVisionAPI $google_VisionAPI.
    */
-  public function __construct(GoogleVisionAPI $image_Request) {
+  public function __construct(GoogleVisionAPI $google_VisionAPI) {
 
-    $this->request = $image_Request;
+    $this->googleVisionAPI = $google_VisionAPI;
   }
 
   /**
    * Function to retrieve labels for given image.
    *
-   * @param file URI $filepath.
+   * @param string $filepath.
    *
    * @return array $req.
    */
   public function labelDetection($filepath) {
 
-    $req = $this->request->makeRequestForLabels($filepath);
+    $req = $this->googleVisionAPI->makeRequestForLabels($filepath);
     return $req;
   }
 
   /**
    * Function to detect landmarks within a given image.
    *
-   * @param file URI $filepath.
+   * @param string $filepath.
    *
    * @return array $req.
    */
   public function landmarkDetection($filepath) {
 
-    $req = $this->request->makeRequestForLandmark($filepath);
+    $req = $this->googleVisionAPI->makeRequestForLandmark($filepath);
     return $req;
   }
 
   /**
    * Function to detect logos of famous brands within a given image.
    *
-   * @param file URI $filepath.
+   * @param string $filepath.
    *
    * @return array $req.
    */
   public function logoDetection($filepath) {
 
-    $req = $this->request->makeRequestForLogo($filepath);
+    $req = $this->googleVisionAPI->makeRequestForLogo($filepath);
     return $req;
   }
 
   /**
    * Function to detect explicit content within a given image.
    *
-   * @param file URI $filepath.
+   * @param string $filepath.
    *
    * @return array $req.
    */
   public function safeSearchDetection($filepath) {
 
-    $req = $this->request->makeRequestForSafeSearch($filepath);
+    $req = $this->googleVisionAPI->makeRequestForSafeSearch($filepath);
     return $req;
   }
 
   /**
    * Function to retrieve texts within a given image.
    *
-   * @param file URI $filepath.
+   * @param string $filepath.
    *
    * @return array $req.
    */
   public function opticalCharacterRecognition($filepath) {
 
-    $req = $this->request->makeRequestForOCR($filepath);
+    $req = $this->googleVisionAPI->makeRequestForOCR($filepath);
     return $req;
   }
 
   /**
    * Function to detect faces from a given image.
    *
-   * @param file URI $filepath.
+   * @param string $filepath.
    *
    * @return array $req.
    */
   public function faceDetection($filepath) {
 
-    $req = $this->request->makeRequestForFaceDetection($filepath);
+    $req = $this->googleVisionAPI->makeRequestForFaceDetection($filepath);
     return $req;
   }
 
   /**
    * Function to retrieve image attributes from a given image.
    *
-   * @param file URI $filepath.
+   * @param string $filepath.
    *
    * @return array $req.
    */
   public function imageAttributes($filepath) {
 
-    $req = $this->request->makeRequestForImageAttributes($filepath);
+    $req = $this->googleVisionAPI->makeRequestForImageAttributes($filepath);
     return $req;
   }
 
diff --git a/src/GoogleVisionAPI.php b/src/GoogleVisionAPI.php
index ac6885d..5603862 100755
--- a/src/GoogleVisionAPI.php
+++ b/src/GoogleVisionAPI.php
@@ -1,9 +1,5 @@
 <?php
 
-/**
- * Google vision connector.
- */
-
 namespace Drupal\google_vision;
 
 use Drupal\Core\Config\ConfigFactoryInterface;
@@ -21,26 +17,45 @@ class GoogleVisionAPI {
   protected $configFactory;
 
   /**
-   * Constructor.
+   * The HTTP client to fetch the feed data with.
+   *
+   * @var \GuzzleHttp\ClientInterface
+   */
+  protected $httpClient;
+
+  /**
+   * Stores the API key.
+   *
+   * @var int
+   */
+  protected $apiKey;
+
+  /**
+   * Construct a GoogleVisionAPI object.
    *
    * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory.
+   *
+   * @param \GuzzleHttp\ClientInterface $http_client
+   *   A Guzzle client object.
+   *
+   * @todo Throw the exception when the api key is not set on status page.
    */
-  public function __construct(ConfigFactoryInterface $config_factory) {
+  public function __construct(ConfigFactoryInterface $config_factory, ClientInterface $http_client) {
     $this->configFactory = $config_factory;
+    $this->httpClient = $http_client;
+    $this->apiKey = $this->configFactory->get('google_vision.settings')->get('api_key');
   }
 
   /**
    * Function to retrieve labels for given image.
    *
-   * @param file URI $filepath.
+   * @param string $filepath.
    *
    * @return Array.
    */
   public function makeRequestForLabels($filepath) {
-    $config = $this->configFactory->get('google_vision.settings');
-    $api_key = $config->get('api_key');
-    if (!$api_key) {
+    if (!$this->apiKey) {
       return FALSE;
     }
 
@@ -65,9 +80,8 @@ class GoogleVisionAPI {
       ],
     ];
 
-    $url = 'https://vision.googleapis.com/v1/images:annotate?key=' . $api_key;
-    $client = \Drupal::httpClient();
-    $response = $client->post($url, [
+    $url = 'https://vision.googleapis.com/v1/images:annotate?key=' . $this->apiKey;
+    $response = $this->httpClient->post($url, [
       RequestOptions::JSON => $data,
       RequestOptions::HEADERS => ['Content-Type' => 'application/json'],
     ]);
@@ -79,14 +93,12 @@ class GoogleVisionAPI {
   /**
    * Function to detect landmarks within a given image.
    *
-   * @param file URI $filepath.
+   * @param string $filepath.
    *
    * @return Array.
    */
   public function makeRequestForLandmark($filepath) {
-    $config = $this->configFactory->get('google_vision.settings');
-    $api_key = $config->get('api_key');
-    if (!$api_key) {
+    if (!$this->apiKey) {
       return FALSE;
     }
 
@@ -111,9 +123,8 @@ class GoogleVisionAPI {
       ],
     ];
 
-    $url = 'https://vision.googleapis.com/v1/images:annotate?key=' . $api_key;
-    $client = \Drupal::httpClient();
-    $response = $client->post($url, [
+    $url = 'https://vision.googleapis.com/v1/images:annotate?key=' . $this->apiKey;
+    $response = $this->httpClient->post($url, [
       RequestOptions::JSON => $data,
       RequestOptions::HEADERS => ['Content-Type' => 'application/json'],
     ]);
@@ -125,14 +136,12 @@ class GoogleVisionAPI {
   /**
    * Function to detect logos of famous brands within a given image.
    *
-   * @param file URI $filepath.
+   * @param string $filepath.
    *
    * @return Array.
    */
   public function makeRequestForLogo($filepath) {
-    $config = $this->configFactory->get('google_vision.settings');
-    $api_key = $config->get('api_key');
-    if (!$api_key) {
+    if (!$this->apiKey) {
       return FALSE;
     }
 
@@ -157,9 +166,8 @@ class GoogleVisionAPI {
       ],
     ];
 
-    $url = 'https://vision.googleapis.com/v1/images:annotate?key=' . $api_key;
-    $client = \Drupal::httpClient();
-    $response = $client->post($url, [
+    $url = 'https://vision.googleapis.com/v1/images:annotate?key=' . $this->apiKey;
+    $response = $this->httpClient->post($url, [
       RequestOptions::JSON => $data,
       RequestOptions::HEADERS => ['Content-Type' => 'application/json'],
     ]);
@@ -171,14 +179,12 @@ class GoogleVisionAPI {
   /**
    * Function to detect explicit content within a given image.
    *
-   * @param file URI $filepath.
+   * @param string $filepath.
    *
    * @return Array.
    */
   public function makeRequestForSafeSearch($filepath) {
-    $config = $this->configFactory->get('google_vision.settings');
-    $api_key = $config->get('api_key');
-    if (!$api_key) {
+    if (!$this->apiKey) {
       return FALSE;
     }
 
@@ -203,9 +209,8 @@ class GoogleVisionAPI {
       ],
     ];
 
-    $url = 'https://vision.googleapis.com/v1/images:annotate?key=' . $api_key;
-    $client = \Drupal::httpClient();
-    $response = $client->post($url, [
+    $url = 'https://vision.googleapis.com/v1/images:annotate?key=' . $this->apiKey;
+    $response = $this->httpClient->post($url, [
       RequestOptions::JSON => $data,
       RequestOptions::HEADERS => ['Content-Type' => 'application/json'],
     ]);
@@ -217,14 +222,12 @@ class GoogleVisionAPI {
   /**
    * Function to retrieve texts for given image.
    *
-   * @param file URI $filepath.
+   * @param string $filepath.
    *
    * @return Array.
    */
   public function makeRequestForOCR($filepath) {
-    $config = $this->configFactory->get('google_vision.settings');
-    $api_key = $config->get('api_key');
-    if (!$api_key) {
+    if (!$this->apiKey) {
       return FALSE;
     }
 
@@ -249,9 +252,8 @@ class GoogleVisionAPI {
       ],
     ];
 
-    $url = 'https://vision.googleapis.com/v1/images:annotate?key=' . $api_key;
-    $client = \Drupal::httpClient();
-    $response = $client->post($url, [
+    $url = 'https://vision.googleapis.com/v1/images:annotate?key=' . $this->apiKey;
+    $response = $this->httpClient->post($url, [
       RequestOptions::JSON => $data,
       RequestOptions::HEADERS => ['Content-Type' => 'application/json'],
     ]);
@@ -263,14 +265,12 @@ class GoogleVisionAPI {
   /**
    * Function to fetch faces from a given image.
    *
-   * @param file URI $filepath.
+   * @param string $filepath.
    *
    * @return Array.
    */
   public function makeRequestForFaceDetection($filepath) {
-    $config = $this->configFactory->get('google_vision.settings');
-    $api_key = $config->get('api_key');
-    if (!$api_key) {
+    if (!$this->apiKey) {
       return FALSE;
     }
 
@@ -295,9 +295,8 @@ class GoogleVisionAPI {
       ],
     ];
 
-    $url = 'https://vision.googleapis.com/v1/images:annotate?key=' . $api_key;
-    $client = \Drupal::httpClient();
-    $response = $client->post($url, [
+    $url = 'https://vision.googleapis.com/v1/images:annotate?key=' . $this->apiKey;
+    $response = $this->httpClient->post($url, [
       RequestOptions::JSON => $data,
       RequestOptions::HEADERS => ['Content-Type' => 'application/json'],
     ]);
@@ -309,14 +308,12 @@ class GoogleVisionAPI {
   /**
    * Function to retrieve image attributes for given image.
    *
-   * @param file URI $filepath.
+   * @param string $filepath.
    *
    * @return Array.
    */
   public function makeRequestForImageAttributes($filepath) {
-    $config = $this->configFactory->get('google_vision.settings');
-    $api_key = $config->get('api_key');
-    if (!$api_key) {
+    if (!$this->apiKey) {
       return FALSE;
     }
 
@@ -341,9 +338,8 @@ class GoogleVisionAPI {
       ],
     ];
 
-    $url = 'https://vision.googleapis.com/v1/images:annotate?key=' . $api_key;
-    $client = \Drupal::httpClient();
-    $response = $client->post($url, [
+    $url = 'https://vision.googleapis.com/v1/images:annotate?key=' . $this->apiKey;
+    $response = $this->httpClient->post($url, [
       RequestOptions::JSON => $data,
       RequestOptions::HEADERS => ['Content-Type' => 'application/json'],
     ]);