Add `deserialized_content` to the response

This is a helper method that aims to centralize response's content
deserialization and remove the burden of this process from the client.

Partially-Implements: python-marconiclient-v1
Change-Id: Ia98e9b9cdf5bdd88f9f2cdeda39b49d2192a60eb

marconiclient/queues/v1/core.py

@@ -51,7 +51,8 @@ def _common_queue_ops(operation, transport, request, name, callback=None):
     """
     request.operation = operation
     request.params['queue_name'] = name
-    return transport.send(request)
+    resp = transport.send(request)
+    return resp.deserialized_content
 
 
 def queue_create(transport, request, name, callback=None):
@@ -72,9 +73,8 @@ def queue_exists(transport, request, name, callback=None):
 
 def queue_get_metadata(transport, request, name, callback=None):
     """Gets queue metadata."""
-    resp = _common_queue_ops('queue_get_metadata', transport,
+    return _common_queue_ops('queue_get_metadata', transport,
                              request, name, callback=callback)
-    return json.loads(resp.content)
 
 
 def queue_set_metadata(transport, request, name, metadata, callback=None):
@@ -132,7 +132,7 @@ def message_list(transport, request, queue_name, callback=None, **kwargs):
         # `links` and `messages`
         return {'links': [], 'messages': []}
 
-    return json.loads(resp.content)
+    return resp.deserialized_content
 
 
 def message_post(transport, request, queue_name, messages, callback=None):
@@ -157,7 +157,7 @@ def message_post(transport, request, queue_name, messages, callback=None):
     request.content = json.dumps(messages)
 
     resp = transport.send(request)
-    return json.loads(resp.content)
+    return resp.deserialized_content
 
 
 def message_get(transport, request, queue_name, message_id, callback=None):
@@ -182,7 +182,7 @@ def message_get(transport, request, queue_name, message_id, callback=None):
     request.params['message_id'] = message_id
 
     resp = transport.send(request)
-    return json.loads(resp.content)
+    return resp.deserialized_content
 
 
 def message_get_many(transport, request, queue_name, messages, callback=None):
@@ -207,7 +207,7 @@ def message_get_many(transport, request, queue_name, messages, callback=None):
     request.params['ids'] = messages
 
     resp = transport.send(request)
-    return json.loads(resp.content)
+    return resp.deserialized_content
 
 
 def message_delete(transport, request, queue_name, message_id, callback=None):
@@ -231,4 +231,4 @@ def message_delete(transport, request, queue_name, message_id, callback=None):
     request.params['queue_name'] = queue_name
     request.params['message_id'] = message_id
 
-    return transport.send(request)
+    transport.send(request)

marconiclient/transport/response.py

@@ -13,6 +13,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import json
+
 
 class Response(object):
     """Common response class for Marconiclient.
@@ -29,9 +31,17 @@ class Response(object):
     :type: dict
     """
 
-    __slots__ = ('request', 'content', 'headers')
+    __slots__ = ('request', 'content', 'headers', '_deserialized')
 
     def __init__(self, request, content, headers=None):
         self.request = request
         self.content = content
         self.headers = headers or {}
+
+        self._deserialized = None
+
+    @property
+    def deserialized_content(self):
+        if not self._deserialized and self.content:
+            self._deserialized = json.loads(self.content)
+        return self._deserialized

tests/unit/queues/v1/test_core.py

@@ -33,7 +33,7 @@ class TestV1Core(base.TestBase):
     def test_queue_create(self):
         with mock.patch.object(self.transport, 'send',
                                autospec=True) as send_method:
-            send_method.return_value = None
+            send_method.return_value = response.Response(None, None)
 
             req = request.Request()
             core.queue_create(self.transport, req, 'test')
@@ -42,7 +42,7 @@ class TestV1Core(base.TestBase):
     def test_queue_delete(self):
         with mock.patch.object(self.transport, 'send',
                                autospec=True) as send_method:
-            send_method.return_value = None
+            send_method.return_value = response.Response(None, None)
 
             req = request.Request()
             core.queue_delete(self.transport, req, 'test')
@@ -51,7 +51,7 @@ class TestV1Core(base.TestBase):
     def test_queue_exists(self):
         with mock.patch.object(self.transport, 'send',
                                autospec=True) as send_method:
-            send_method.return_value = None
+            send_method.return_value = response.Response(None, None)
 
             req = request.Request()
             ret = core.queue_exists(self.transport, req, 'test')
@@ -82,7 +82,7 @@ class TestV1Core(base.TestBase):
         update_data = {'some': 'data'}
         with mock.patch.object(self.transport, 'send',
                                autospec=True) as send_method:
-            send_method.return_value = None
+            send_method.return_value = response.Response(None, None)
 
             req = request.Request()
             core.queue_exists(self.transport, req, update_data, 'test')