Router: Add class FakeRouter to test "router xxx" command

A unit test class similar to FakeServer, which is able to fake one
or more routers. It will be used by the router CRUD patches.

Change-Id: I9b87c6c95282902c3a829da51229a35d4265a1e4
Implements: blueprint neutron-client
Partial-bug: #1519503

openstackclient/tests/network/v2/fakes.py

@@ -140,3 +140,84 @@ class FakeNetwork(object):
         if networks is None:
             networks = FakeNetwork.create_networks(count)
         return mock.MagicMock(side_effect=networks)
+
+
+class FakeRouter(object):
+    """Fake one or more routers."""
+
+    @staticmethod
+    def create_one_router(attrs={}, methods={}):
+        """Create a fake router.
+
+        :param Dictionary attrs:
+            A dictionary with all attributes
+        :param Dictionary methods:
+            A dictionary with all methods
+        :return:
+            A FakeResource object, with id, name, admin_state_up,
+            status, tenant_id
+        """
+        # Set default attributes.
+        router_attrs = {
+            'id': 'router-id-' + uuid.uuid4().hex,
+            'name': 'router-name-' + uuid.uuid4().hex,
+            'status': 'ACTIVE',
+            'admin_state_up': True,
+            'distributed': False,
+            'ha': False,
+            'tenant_id': 'project-id-' + uuid.uuid4().hex,
+            'routes': [],
+            'external_gateway_info': {},
+        }
+
+        # Overwrite default attributes.
+        router_attrs.update(attrs)
+
+        # Set default methods.
+        router_methods = {}
+
+        # Overwrite default methods.
+        router_methods.update(methods)
+
+        router = fakes.FakeResource(info=copy.deepcopy(router_attrs),
+                                    methods=copy.deepcopy(router_methods),
+                                    loaded=True)
+        return router
+
+    @staticmethod
+    def create_routers(attrs={}, methods={}, count=2):
+        """Create multiple fake routers.
+
+        :param Dictionary attrs:
+            A dictionary with all attributes
+        :param Dictionary methods:
+            A dictionary with all methods
+        :param int count:
+            The number of routers to fake
+        :return:
+            A list of FakeResource objects faking the routers
+        """
+        routers = []
+        for i in range(0, count):
+            routers.append(FakeRouter.create_one_router(attrs, methods))
+
+        return routers
+
+    @staticmethod
+    def get_routers(routers=None, count=2):
+        """Get an iterable MagicMock object with a list of faked routers.
+
+        If routers list is provided, then initialize the Mock object with the
+        list. Otherwise create one.
+
+        :param List routers:
+            A list of FakeResource objects faking routers
+        :param int count:
+            The number of routers to fake
+        :return:
+            An iterable Mock object with side_effect set to a list of faked
+            routers
+        """
+        if routers is None:
+            routers = FakeRouter.create_routers(count)
+        return mock.MagicMock(side_effect=routers)