initial kademlia files

1 files changed, 72 insertions, 0 deletions

diff --git a/kademlia/msgformat.py b/kademlia/msgformat.py
new file mode 100644
index 0000000..c0c5ce8
--- /dev/null
+++ b/kademlia/msgformat.py
@@ -0,0 +1,72 @@
+#!/usr/bin/env python
+#
+# This library is free software, distributed under the terms of
+# the GNU Lesser General Public License Version 3, or any later version.
+# See the COPYING file included in this archive
+#
+# The docstrings in this module contain epytext markup; API documentation
+# may be created by processing this file with epydoc: http://epydoc.sf.net
+
+import msgtypes
+
+class MessageTranslator(object):
+    """ Interface for RPC message translators/formatters
+    
+    Classes inheriting from this should provide a translation services between
+    the classes used internally by this Kademlia implementation and the actual
+    data that is transmitted between nodes.
+    """
+    def fromPrimitive(self, msgPrimitive):
+        """ Create an RPC Message from a message's string representation
+        
+        @param msgPrimitive: The unencoded primitive representation of a message
+        @type msgPrimitive: str, int, list or dict
+        
+        @return: The translated message object
+        @rtype: entangled.kademlia.msgtypes.Message
+        """
+    
+    def toPrimitive(self, message):
+        """ Create a string representation of a message
+        
+        @param message: The message object
+        @type message: msgtypes.Message
+        
+        @return: The message's primitive representation in a particular
+                 messaging format
+        @rtype: str, int, list or dict
+        """
+        
+class DefaultFormat(MessageTranslator):
+    """ The default on-the-wire message format for this library """
+    typeRequest, typeResponse, typeError = range(3)
+    headerType, headerMsgID, headerNodeID, headerPayload, headerArgs = range(5)
+    
+    def fromPrimitive(self, msgPrimitive):
+        msgType = msgPrimitive[self.headerType]
+        if msgType == self.typeRequest:
+            msg = msgtypes.RequestMessage(msgPrimitive[self.headerNodeID], msgPrimitive[self.headerPayload], msgPrimitive[self.headerArgs], msgPrimitive[self.headerMsgID])
+        elif msgType == self.typeResponse:
+            msg = msgtypes.ResponseMessage(msgPrimitive[self.headerMsgID], msgPrimitive[self.headerNodeID], msgPrimitive[self.headerPayload])
+        elif msgType == self.typeError:
+            msg = msgtypes.ErrorMessage(msgPrimitive[self.headerMsgID], msgPrimitive[self.headerNodeID], msgPrimitive[self.headerPayload], msgPrimitive[self.headerArgs])
+        else:
+            # Unknown message, no payload
+            msg = msgtypes.Message(msgPrimitive[self.headerMsgID], msgPrimitive[self.headerNodeID])
+        return msg
+    
+    def toPrimitive(self, message):    
+        msg = {self.headerMsgID:  message.id,
+               self.headerNodeID: message.nodeID}
+        if isinstance(message, msgtypes.RequestMessage):
+            msg[self.headerType] = self.typeRequest
+            msg[self.headerPayload] = message.request
+            msg[self.headerArgs] = message.args
+        elif isinstance(message, msgtypes.ErrorMessage):
+            msg[self.headerType] = self.typeError
+            msg[self.headerPayload] = message.exceptionType
+            msg[self.headerArgs] = message.response
+        elif isinstance(message, msgtypes.ResponseMessage):
+            msg[self.headerType] = self.typeResponse
+            msg[self.headerPayload] = message.response
+        return msg