refactored routedhost into router passed to swarm

libp2p/network/swarm.py

@@ -20,6 +20,7 @@ class Swarm(INetwork):
         self.listeners = dict()
         self.stream_handlers = dict()
         self.transport = None
+        self.router = None
 
         # Protocol muxing
         self.multiselect = Multiselect()
@@ -57,8 +58,10 @@ class Swarm(INetwork):
         if not addrs:
             raise SwarmException("No known addresses to peer")
 
-        # TODO: define logic to choose which address to use, or try them all ?
-        multiaddr = addrs[0]
+        if not self.router:
+            multiaddr = addrs[0]
+        else:
+            multiaddr = self.router.find_peer(peer_id)
 
         if peer_id in self.connections:
             # If muxed connection already exists for peer_id,
@@ -187,6 +190,9 @@ class Swarm(INetwork):
         # TODO: Support more than one transport
         self.transport = transport
 
+    def add_router(self, router):
+        self.router = router
+
 def create_generic_protocol_handler(swarm):
     """
     Create a generic protocol handler from the given swarm. We use swarm