Add support for raw data flag

bmemcached/client/replicating.py

@@ -26,20 +26,24 @@ class ReplicatingClient(object):
     :type unpickler: function
     :param socket_timeout: The timeout applied to memcached connections.
     :type socket_timeout: float
+    :param raw_data: Whether this client should read and write only binary strings, rather than storing type information in the 'opaque' field. This is useful when interacting with memcached keys which already have the 'opaque value' set to something, to avoid misinterpreting data.
+    :type raw_data: bool
     """
     def __init__(self, servers=('127.0.0.1:11211',), username=None,
                  password=None, compression=None,
                  socket_timeout=SOCKET_TIMEOUT,
                  pickle_protocol=0,
                  pickler=pickle.Pickler,
-                 unpickler=pickle.Unpickler):
+                 unpickler=pickle.Unpickler,
+                 raw_data=False):
         self.username = username
         self.password = password
         self.compression = compression
         self.socket_timeout = socket_timeout
         self.pickle_protocol = pickle_protocol
         self.pickler = pickler
         self.unpickler = unpickler
+        self.raw_data = raw_data
         self.set_servers(servers)
 
     @property
@@ -69,6 +73,7 @@ def set_servers(self, servers):
             pickle_protocol=self.pickle_protocol,
             pickler=self.pickler,
             unpickler=self.unpickler,
+            raw_data=self.raw_data,
         ) for server in servers]
 
     def _set_retry_delay(self, value):

bmemcached/protocol.py

@@ -99,7 +99,7 @@ class Protocol(threading.local):
     COMPRESSION_THRESHOLD = 128
 
     def __init__(self, server, username=None, password=None, compression=None, socket_timeout=None,
-                 pickle_protocol=None, pickler=None, unpickler=None):
+                 pickle_protocol=None, pickler=None, unpickler=None, raw_data=False):
         super(Protocol, self).__init__()
         self.server = server
         self._username = username
@@ -122,6 +122,8 @@ def __init__(self, server, username=None, password=None, compression=None, socke
             self.host = self.port = None
             self.set_retry_delay(0)
 
+        self.raw_data = raw_data
+
     @property
     def server_uses_unix_socket(self):
         return self.host is None
@@ -332,6 +334,12 @@ def serialize(self, value, compress_level=-1):
         :rtype: str
         """
         flags = 0
+
+        if self.raw_data:
+            if compress_level > 0:
+                raise MemcachedException("Compression is not possible when in 'raw data' mode")
+            return flags, value
+
         if isinstance(value, binary_type):
             flags |= self.FLAGS['binary']
         elif isinstance(value, text_type):
@@ -376,6 +384,9 @@ def deserialize(self, value, flags):
         """
         FLAGS = self.FLAGS
 
+        if self.raw_data:
+            return value
+
         if flags & FLAGS['compressed']:  # pragma: no branch
             value = self.compression.decompress(value)