[AIRFLOW-1793] Use docker_url instead of invalid base_url

Closes #2998 from kodieg/patch-3

airflow/operators/docker_operator.py

@@ -147,7 +147,7 @@ class DockerOperator(BaseOperator):
     def get_hook(self):
         return DockerHook(
             docker_conn_id=self.docker_conn_id,
-            base_url=self.base_url,
+            base_url=self.docker_url,
             version=self.api_version,
             tls=self.__get_tls_config()
         )

tests/operators/docker_operator.py

@@ -187,8 +187,10 @@ class DockerOperatorTestCase(unittest.TestCase):
             'Hook called though no docker_conn_id configured'
         )
 
+    @mock.patch('airflow.operators.docker_operator.DockerHook')
     @mock.patch('airflow.operators.docker_operator.Client')
-    def test_execute_with_docker_conn_id_use_hook(self, operator_client_mock):
+    def test_execute_with_docker_conn_id_use_hook(self, operator_client_mock,
+                                                  operator_docker_hook):
         # Mock out a Docker client, so operations don't raise errors
         client_mock = mock.Mock(name='DockerOperator.Client mock', spec=Client)
         client_mock.images.return_value = []
@@ -209,19 +211,16 @@ class DockerOperatorTestCase(unittest.TestCase):
         # Mock out the DockerHook
         hook_mock = mock.Mock(name='DockerHook mock', spec=DockerHook)
         hook_mock.get_conn.return_value = client_mock
-        operator.get_hook = mock.Mock(
-            name='DockerOperator.get_hook mock',
-            spec=DockerOperator.get_hook,
-            return_value=hook_mock
-        )
+        operator_docker_hook.return_value = hook_mock
 
         operator.execute(None)
+
         self.assertEqual(
             operator_client_mock.call_count, 0,
             'Client was called on the operator instead of the hook'
         )
         self.assertEqual(
-            operator.get_hook.call_count, 1,
+            operator_docker_hook.call_count, 1,
             'Hook was not called although docker_conn_id configured'
         )
         self.assertEqual(