responder separated from controller (first step for #36)

core/responder.py

@@ -0,0 +1,54 @@
+"""
+This is the server part of the node, where queries are parsed and responses
+created.
+
+"""
+import logging, logging_conf
+
+import message
+import tracker
+import token_manager
+
+logger = logging.getLogger('dht')
+
+NUM_NODES = 8
+
+class Responder(object):
+
+    def __init__(self, my_id, routing_m, msg_f):
+        self._my_id = my_id
+        self._routing_m = routing_m
+        self.msg_f = msg_f
+        self._tracker = tracker.Tracker()
+        self._token_m = token_manager.TokenManager()
+
+    def get_response(self, msg):
+        if msg.query == message.PING:
+            return self.msg_f.outgoing_ping_response(msg.src_node)
+        elif msg.query == message.FIND_NODE:
+            log_distance = msg.target.log_distance(self._my_id)
+            rnodes = self._routing_m.get_closest_rnodes(log_distance,
+                                                        NUM_NODES, False)
+            #TODO: return the closest rnodes to the target instead of the 8
+            #first in the bucket.
+            return self.msg_f.outgoing_find_node_response(
+                msg.src_node, rnodes)
+        elif msg.query == message.GET_PEERS:
+            token = self._token_m.get()
+            log_distance = msg.info_hash.log_distance(self._my_id)
+            rnodes = self._routing_m.get_closest_rnodes(log_distance,
+                                                        NUM_NODES, False)
+            #TODO: return the closest rnodes to the target instead of the 8
+            #first in the bucket.
+            peers = self._tracker.get(msg.info_hash)
+            if peers:
+                logger.debug('RESPONDING with PEERS:\n%r' % peers)
+            return self.msg_f.outgoing_get_peers_response(
+                msg.src_node, token, nodes=rnodes, peers=peers)
+        elif msg.query == message.ANNOUNCE_PEER:
+            peer_addr = (msg.src_addr[0], msg.bt_port)
+            self._tracker.put(msg.info_hash, peer_addr)
+            return self.msg_f.outgoing_announce_peer_response(msg.src_node)
+        else:
+            logger.debug('Invalid QUERY: %r' % (msg.query))
+            #TODO: maybe send an error back?