packet lib: add Packet.__contains__

you can do something like:
  if arp.arp in Packet(msg.data):

  a = arp.arp(...)
  if a in Packet(msg.data):

  >>> from ryu.lib.packet import packet
  >>> from ryu.lib.packet import arp
  >>> a = arp.arp_ip(1, 0, 0, 0, 0)
  >>> p = packet.Packet()
  >>> p.protocols = [a]
  >>> arp.arp in p
  True
  >>> a in p
  True

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

1 files changed, 8 insertions, 0 deletions

diff --git a/ryu/lib/packet/packet.py b/ryu/lib/packet/packet.py
index def580b6..ff06cc3a 100644
--- a/ryu/lib/packet/packet.py
+++ b/ryu/lib/packet/packet.py
@@ -13,6 +13,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import inspect
+
 from . import packet_base
 from . import ethernet
 
@@ -109,3 +111,9 @@ class Packet(object):
 
     def __len__(self):
         return len(self.protocols)
+
+    def __contains__(self, protocol):
+        if (inspect.isclass(protocol) and
+                issubclass(protocol, packet_base.PacketBase)):
+            return protocol in [p.__class__ for p in self.protocols]
+        return protocol in self.protocols