Add basic support for multiaddr addresses and improvement around peer id (#75)

* Improved peer ID construction and usage

* peer id object is directly passed to the network

no need to cast from a string to an ID

* don't base64 encode the peer id when loading from public key

* use proper multiaddr address

- keep multiaddr object into peerstore instead of string
- update network code to use new multiaddr lib
- update tests and example

* don't instanciate peerstore object in constructor

This has side effect where the same peerstore
is used for different instance of Libp2p

* add connect method to basic_host

* use zaibon's fork of sbuss/py-multiaddr

* lint

host/basic_host.py

@@ -1,11 +1,13 @@
-from .host_interface import IHost
+import multiaddr
 
+from .host_interface import IHost
 
 # Upon host creation, host takes in options,
 # including the list of addresses on which to listen.
 # Host then parses these options and delegates to its Network instance,
 # telling it to listen on the given listen addresses.
 
+
 class BasicHost(IHost):
 
     # default options constructor
@@ -36,6 +38,18 @@ class BasicHost(IHost):
         :return: mux instance of host
         """
 
+    def get_addrs(self):
+        """
+        :return: all the multiaddr addresses this host is listening too
+        """
+        p2p_part = multiaddr.Multiaddr('/ipfs/{}'.format(self.get_id().pretty()))
+
+        addrs = []
+        for transport in self.network.listeners.values():
+            for addr in transport.get_addrs():
+                addrs.append(addr.encapsulate(p2p_part))
+        return addrs
+
     def set_stream_handler(self, protocol_id, stream_handler):
         """
         set stream handler for host
@@ -45,7 +59,6 @@ class BasicHost(IHost):
         """
         return self.network.set_stream_handler(protocol_id, stream_handler)
 
-
     # protocol_id can be a list of protocol_ids
     # stream will decide which protocol_id to run on
     async def new_stream(self, peer_id, protocol_ids):
@@ -56,3 +69,22 @@ class BasicHost(IHost):
         """
         stream = await self.network.new_stream(peer_id, protocol_ids)
         return stream
+
+    async def connect(self, peer_info):
+        """
+        connect ensures there is a connection between this host and the peer with
+        given peer_info.peer_id. connect will absorb the addresses in peer_info into its internal
+        peerstore. If there is not an active connection, connect will issue a
+        dial, and block until a connection is open, or an error is
+        returned.
+
+        :param peer_info: peer_info of the host we want to connect to
+        :type peer_info: peer.peerinfo.PeerInfo
+        """
+        self.peerstore.add_addrs(peer_info.peer_id, peer_info.addrs, 10)
+
+        # there is already a connection to this peer
+        if peer_info.peer_id in self.network.connections:
+            return
+
+        await self.network.dial_peer(peer_info.peer_id)