diff --git a/src/Tests/ApiKeyConfigurationTest.php b/src/Tests/ApiKeyConfigurationTest.php
index 1e414e6..608f11c 100755
--- a/src/Tests/ApiKeyConfigurationTest.php
+++ b/src/Tests/ApiKeyConfigurationTest.php
@@ -21,6 +21,15 @@ class ApiKeyConfigurationTest extends WebTestBase {
   public static $modules = ['google_vision'];
 
   /**
+   * Disable strict config schema checking.
+   *
+   * The schema is verified at the end of running the update.
+   *
+   * @var bool
+   */
+  protected $strictConfigSchema = FALSE;
+
+  /**
    * A user with permission to create and edit books and to administer blocks.
    *
    * @var object
@@ -53,4 +62,21 @@ class ApiKeyConfigurationTest extends WebTestBase {
     $this->assertLinkByHref(Url::fromRoute('google_vision.settings')->toString());
 
   }
+
+  /**
+   * Test to verify that it is stored successfully.
+   */
+  function testKeyStorage() {
+    $this->drupalGet(Url::fromRoute('google_vision.settings'));
+    $this->assertResponse(200);
+    $this->assertFieldByName('api_key', '', 'The key is not set currently');
+    $apiKey = $this->randomString(40);
+    $data = array(
+      'api_key' => $apiKey,
+    );
+    $this->drupalPostForm(Url::fromRoute('google_vision.settings'), $data, t('Save configuration'));
+    $this->drupalGet(Url::fromRoute('google_vision.settings'));
+    $this->assertResponse(200);
+    $this->assertFieldByName('api_key', $apiKey, 'The key has been saved');
+  }
 }