Add support for pop implemented in v1.1

This patch implements pop in the client library. Pop is a new operation
that has been implemented in v1.1. It allows a client to remove N
messages from the top of queue. Although pop is a query parameter in the
server, it has been implemented as if it were an action.

Partially-Implements blueprint: api-v1.1

Change-Id: I29b771a6167185033821139bd795311f1a25a5e1

tests/unit/queues/v1/test_core.py

@@ -221,3 +221,20 @@ class TestV1Core(base.TestBase):
 
             req = request.Request()
             core.health(self.transport, req)
+
+
+class TestV1_1Core(TestV1Core):
+
+    def test_message_pop(self):
+        with mock.patch.object(self.transport, 'send',
+                               autospec=True) as send_method:
+            resp = response.Response(None, '{}')
+            send_method.return_value = resp
+
+            req = request.Request()
+            core.message_pop(self.transport, req,
+                             'test', count=5)
+
+            self.assertIn('queue_name', req.params)
+            self.assertIn('pop', req.params)
+            self.assertEqual(req.params['pop'], 5)

tests/unit/queues/v1/test_queues.py

@@ -25,7 +25,7 @@ class QueuesV1QueueHttpUnitTest(queues.QueuesV1QueueUnitTest):
     version = 1
 
 
-class QueuesV1_1QueueHttpUnitTest(queues.QueuesV1QueueUnitTest):
+class QueuesV1_1QueueHttpUnitTest(queues.QueuesV1_1QueueUnitTest):
 
     transport_cls = http.HttpTransport
     url = 'http://127.0.0.1:8888/v1.1'

zaqarclient/queues/v1/api.py

@@ -224,3 +224,16 @@ class V1(api.Api):
 
 class V1_1(V1):
     label = 'v1.1'
+
+
+V1_1.schema.update({
+    'message_pop': {
+        'ref': 'queues/{queue_name}/messages/',
+        'method': 'DELETE',
+        'required': ['queue_name', 'pop'],
+        'properties': {
+            'queue_name': {'type': 'string'},
+            'pop': {'type': 'integer'},
+        }
+    },
+})

zaqarclient/queues/v1/core.py

@@ -294,6 +294,30 @@ def message_delete_many(transport, request, queue_name,
     transport.send(request)
 
 
+def message_pop(transport, request, queue_name,
+                count, callback=None):
+    """Pops out `count` messages from `queue_name`
+
+    :param transport: Transport instance to use
+    :type transport: `transport.base.Transport`
+    :param request: Request instance ready to be sent.
+    :type request: `transport.request.Request`
+    :param queue_name: Queue reference name.
+    :type queue_name: `six.text_type`
+    :param count: Number of messages to pop.
+    :type count: int
+    :param callback: Optional callable to use as callback.
+        If specified, this request will be sent asynchronously.
+        (IGNORED UNTIL ASYNC SUPPORT IS COMPLETE)
+    :type callback: Callable object.
+    """
+
+    request.operation = 'message_delete_many'
+    request.params['queue_name'] = queue_name
+    request.params['pop'] = count
+    transport.send(request)
+
+
 def claim_create(transport, request, queue_name, **kwargs):
     """Creates a Claim `claim_id` on the queue `queue_name`
 

zaqarclient/queues/v1/queues.py

@@ -173,6 +173,23 @@ class Queue(object):
         return core.message_delete_many(trans, req, self._name,
                                         set(messages))
 
+    def pop(self, count=1):
+        """Pop `count` messages from the server
+
+        :param count: Number of messages to pop.
+        :type count: int
+
+        :returns: List of messages
+        :rtype: `list`
+        """
+
+        req, trans = self.client._request_and_transport()
+        msgs = core.message_pop(trans, req, self._name, count=count)
+        return iterator._Iterator(self.client,
+                                  msgs,
+                                  'messages',
+                                  message.create_object(self))
+
     def claim(self, id=None, ttl=None, grace=None,
               limit=None):
         return claim_api.Claim(self, id=id, ttl=ttl, grace=grace, limit=limit)

zaqarclient/tests/queues/queues.py

@@ -351,3 +351,52 @@ class QueuesV1QueueFunctionalTest(base.QueuesTestBase):
         messages = queue.delete_messages(*msgs_id)
         self.assertTrue(isinstance(messages, iterator._Iterator))
         self.assertEqual(len(list(messages)), 1)
+
+
+class QueuesV1_1QueueUnitTest(QueuesV1QueueUnitTest):
+
+    def test_message_pop(self):
+        returned = [{
+            'href': '/v1/queues/fizbit/messages/50b68a50d6f5b8c8a7c62b01',
+            'ttl': 800,
+            'age': 790,
+            'body': {'event': 'ActivateAccount', 'mode': 'active'}
+        }, {
+            'href': '/v1/queues/fizbit/messages/50b68a50d6f5b8c8a7c62b02',
+            'ttl': 800,
+            'age': 790,
+            'body': {'event': 'ActivateAccount', 'mode': 'active'}
+        }]
+
+        with mock.patch.object(self.transport, 'send',
+                               autospec=True) as send_method:
+
+            resp = response.Response(None, json.dumps(returned))
+            send_method.return_value = resp
+
+            msg = self.queue.pop(count=2)
+            self.assertIsInstance(msg, iterator._Iterator)
+
+            # NOTE(flaper87): Nothing to assert here,
+            # just checking our way down to the transport
+            # doesn't crash.
+
+
+class QueuesV1_1QueueFunctionalTest(QueuesV1QueueFunctionalTest):
+
+    def test_message_pop(self):
+        queue = self.client.queue("test_queue")
+        queue._get_transport = mock.Mock(return_value=self.transport)
+
+        messages = [
+            {'ttl': 60, 'body': 'Post It 1!'},
+            {'ttl': 60, 'body': 'Post It 2!'},
+            {'ttl': 60, 'body': 'Post It 2!'},
+        ]
+
+        messages = queue.pop(count=2)
+        self.assertTrue(isinstance(messages, iterator._Iterator))
+        self.assertEqual(len(list(messages)), 2)
+
+        remaining = queue.messages()
+        self.assertEqual(len(list(remaining)), 1)