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

examples/chat/chat.py

@@ -8,6 +8,8 @@ import asyncio
 import click
 from libp2p.libp2p import *
 from network.multiaddr import MultiAddr
+from peer.peerinfo import info_from_p2p_addr
+
 
 # TODO: change once muxed_connection supports extracting protocol id from messages
 PROTOCOL_ID = '/echo/1.0.0'
@@ -37,7 +39,7 @@ async def write_data(stream):
 async def run(port, destination):
 
     if not destination:
-        host = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/%s/p2p/hostA" % port])
+        host = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/%s" % port])
 
         async def stream_handler(stream):
             asyncio.ensure_future(read_data(stream))
@@ -48,38 +50,31 @@ async def run(port, destination):
         port = None
         for listener in host.network.listeners.values():
             for addr in listener.get_addrs():
-                addr_dict = addr.to_options()
-                if addr_dict['transport'] == 'tcp':
-                    port = addr_dict['port']
-                    break
+                port = int(addr.value_for_protocol('tcp'))
 
         if not port:
             raise RuntimeError("was not able to find the actual local port")
 
-        print("Run './examples/chat/chat.py --port %s -d /ip4/127.0.0.1/tcp/%s/p2p/%s' on another console.\n" % (int(port)+1, port, host.get_id().pretty()))
+        print("Run './examples/chat/chat.py --port %s -d /ip4/127.0.0.1/tcp/%s/p2p/%s' on another console.\n" %
+              (int(port)+1, port, host.get_id().pretty()))
         print("You can replace 127.0.0.1 with public IP as well.")
         print("\nWaiting for incoming connection\n\n")
 
-
     else:
-        host = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/%s/p2p/hostB" % port])
+        host = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/%s" % port])
 
-        # TODO: improve multiaddr module to have proper function to do this
-        multiaddr = MultiAddr(destination)
-        ss = multiaddr.get_multiaddr_string().split('/')
-        peer_id = ss[-1]
-        addr = '/'.join(ss[:-2])
-
-        # Associate the peer with local ip address (see default parameters of Libp2p())
-        host.get_peerstore().add_addr(peer_id, addr, 10)
+        m = multiaddr.Multiaddr(destination)
+        info = info_from_p2p_addr(m)
+        # Associate the peer with local ip address
+        await host.connect(info)
 
         # Start a stream with the destination.
         # Multiaddress of the destination peer is fetched from the peerstore using 'peerId'.
-        stream = await host.new_stream(peer_id, [PROTOCOL_ID])
+        stream = await host.new_stream(info.peer_id, [PROTOCOL_ID])
 
         asyncio.ensure_future(read_data(stream))
         asyncio.ensure_future(write_data(stream))
-        print("Already connected to peer %s" % addr)
+        print("Already connected to peer %s" % info.addrs[0])
 
 
 @click.command()

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)

host/host_interface.py

@@ -21,6 +21,12 @@ class IHost(ABC):
         :return: mux instance of host
         """
 
+    @abstractmethod
+    def get_addrs(self):
+        """
+        :return: all the multiaddr addresses this host is listening too
+        """
+
     @abstractmethod
     def set_stream_handler(self, protocol_id, stream_handler):
         """
@@ -39,3 +45,16 @@ class IHost(ABC):
         :param protocol_ids: protocol ids that stream can run on
         :return: true if successful
         """
+
+    @abstractmethod
+    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
+        """

libp2p/libp2p.py

@@ -1,5 +1,7 @@
 from Crypto.PublicKey import RSA
+import multiaddr
 from peer.peerstore import PeerStore
+from peer.id import id_from_public_key
 from network.swarm import Swarm
 from host.basic_host import BasicHost
 from transport.upgrader import TransportUpgrader
@@ -11,10 +13,11 @@ async def new_node(id_opt=None, transport_opt=None, \
 
     if id_opt is None:
         new_key = RSA.generate(2048, e=65537)
-        id_opt = new_key.publickey().exportKey("PEM")
+        id_opt = id_from_public_key(new_key.publickey())
         # private_key = new_key.exportKey("PEM")
 
     transport_opt = transport_opt or ["/ip4/127.0.0.1/tcp/8001"]
+    transport_opt = [multiaddr.Multiaddr(t) for t in transport_opt]
     muxer_opt = muxer_opt or ["mplex/6.7.0"]
     sec_opt = sec_opt or ["secio"]
     peerstore = peerstore or PeerStore()

network/network_interface.py

@@ -9,6 +9,16 @@ class INetwork(ABC):
         :return: the peer id
         """
 
+    @abstractmethod
+    def dial_peer(self, peer_id):
+        """
+        dial_peer try to create a connection to peer_id
+
+        :param peer_id: peer if we want to dial
+        :raises SwarmException: raised when no address if found for peer_id
+        :return: muxed connection
+        """
+
     @abstractmethod
     def set_stream_handler(self, protocol_id, stream_handler):
         """

network/swarm.py

@@ -1,18 +1,15 @@
-from peer.id import ID
 from protocol_muxer.multiselect_client import MultiselectClient
 from protocol_muxer.multiselect import Multiselect
 from .network_interface import INetwork
 from .stream.net_stream import NetStream
-from .multiaddr import MultiAddr
 from .connection.raw_connection import RawConnection
 
 
 class Swarm(INetwork):
     # pylint: disable=too-many-instance-attributes, cell-var-from-loop
 
-    def __init__(self, my_peer_id, peerstore, upgrader):
-        self._my_peer_id = my_peer_id
-        self.self_id = ID(my_peer_id)
+    def __init__(self, peer_id, peerstore, upgrader):
+        self.self_id = peer_id
         self.peerstore = peerstore
         self.upgrader = upgrader
         self.connections = dict()
@@ -36,6 +33,39 @@ class Swarm(INetwork):
         self.multiselect.add_handler(protocol_id, stream_handler)
         return True
 
+    async def dial_peer(self, peer_id):
+        """
+        dial_peer try to create a connection to peer_id
+        :param peer_id: peer if we want to dial
+        :raises SwarmException: raised when no address if found for peer_id
+        :return: muxed connection
+        """
+
+        # Get peer info from peer store
+        addrs = self.peerstore.addrs(peer_id)
+
+        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 peer_id in self.connections:
+            # If muxed connection already exists for peer_id,
+            # set muxed connection equal to existing muxed connection
+            muxed_conn = self.connections[peer_id]
+        else:
+            # Transport dials peer (gets back a raw conn)
+            raw_conn = await self.transport.dial(multiaddr)
+
+            # Use upgrader to upgrade raw conn to muxed conn
+            muxed_conn = self.upgrader.upgrade_connection(raw_conn, True)
+
+            # Store muxed connection in connections
+            self.connections[peer_id] = muxed_conn
+
+        return muxed_conn
+
     async def new_stream(self, peer_id, protocol_ids):
         """
         :param peer_id: peer_id of destination
@@ -50,19 +80,7 @@ class Swarm(INetwork):
 
         multiaddr = addrs[0]
 
-        if peer_id in self.connections:
-            # If muxed connection already exists for peer_id,
-            # set muxed connection equal to existing muxed connection
-            muxed_conn = self.connections[peer_id]
-        else:
-            # Transport dials peer (gets back a raw conn)
-            raw_conn = await self.transport.dial(MultiAddr(multiaddr))
-
-            # Use upgrader to upgrade raw conn to muxed conn
-            muxed_conn = self.upgrader.upgrade_connection(raw_conn, True)
-
-            # Store muxed connection in connections
-            self.connections[peer_id] = muxed_conn
+        muxed_conn = await self.dial_peer(peer_id)
 
         # Use muxed conn to open stream, which returns
         # a muxed stream
@@ -92,18 +110,15 @@ class Swarm(INetwork):
                 Call listener listen with the multiaddr
                 Map multiaddr to listener
         """
-        for multiaddr_str in args:
-            if multiaddr_str in self.listeners:
+        for multiaddr in args:
+            if str(multiaddr) in self.listeners:
                 return True
 
-            multiaddr = MultiAddr(multiaddr_str)
-            multiaddr_dict = multiaddr.to_options()
-
             async def conn_handler(reader, writer):
                 # Upgrade reader/write to a net_stream and pass \
                 # to appropriate stream handler (using multiaddr)
-                raw_conn = RawConnection(multiaddr_dict['host'], \
-                    multiaddr_dict['port'], reader, writer)
+                raw_conn = RawConnection(multiaddr.value_for_protocol('ip4'),
+                                         multiaddr.value_for_protocol('tcp'), reader, writer)
                 muxed_conn = self.upgrader.upgrade_connection(raw_conn, False)
 
                 # TODO: Remove protocol id from muxed_conn accept stream or
@@ -124,7 +139,7 @@ class Swarm(INetwork):
             try:
                 # Success
                 listener = self.transport.create_listener(conn_handler)
-                self.listeners[multiaddr_str] = listener
+                self.listeners[str(multiaddr)] = listener
                 await listener.listen(multiaddr)
                 return True
             except IOError:
@@ -138,5 +153,6 @@ class Swarm(INetwork):
         # TODO: Support more than one transport
         self.transport = transport
 
+
 class SwarmException(Exception):
     pass

peer/id.py

@@ -1,4 +1,14 @@
 import base58
+import multihash
+
+# MaxInlineKeyLength is the maximum length a key can be for it to be inlined in
+# the peer ID.
+# * When `len(pubKey.Bytes()) <= MaxInlineKeyLength`, the peer ID is the
+#   identity multihash hash of the public key.
+# * When `len(pubKey.Bytes()) > MaxInlineKeyLength`, the peer ID is the
+#   sha2-256 multihash of the public key.
+MAX_INLINE_KEY_LENGTH = 42
+
 
 class ID:
 
@@ -15,3 +25,42 @@ class ID:
         return "<peer.ID %s*%s>" % (pid[:2], pid[len(pid)-6:])
 
     __repr__ = __str__
+
+    def __eq__(self, other):
+        #pylint: disable=protected-access
+        return self._id_str == other._id_str
+
+    def __hash__(self):
+        return hash(self._id_str)
+
+
+def id_b58_encode(peer_id):
+    """
+    return a b58-encoded string
+    """
+    #pylint: disable=protected-access
+    return base58.b58encode(peer_id._id_str).decode()
+
+
+def id_b58_decode(peer_id_str):
+    """
+    return a base58-decoded peer ID
+    """
+    return ID(base58.b58decode(peer_id_str))
+
+
+def id_from_public_key(key):
+    # export into binary format
+    key_bin = key.exportKey("DER")
+
+    algo = multihash.Func.sha2_256
+    # TODO: seems identity is not yet supported in pymultihash
+    # if len(b) <= MAX_INLINE_KEY_LENGTH:
+    #     algo multihash.func.identity
+
+    mh_digest = multihash.digest(key_bin, algo)
+    return ID(mh_digest.encode())
+
+
+def id_from_private_key(key):
+    return id_from_public_key(key.publickey())

peer/peerinfo.py

@@ -1,5 +1,42 @@
+import multiaddr
+import multiaddr.util
+from peer.id import id_b58_decode
+from peer.peerdata import PeerData
+
+
 class PeerInfo:
 	# pylint: disable=too-few-public-methods
     def __init__(self, peer_id, peer_data):
         self.peer_id = peer_id
         self.addrs = peer_data.get_addrs()
+
+
+def info_from_p2p_addr(addr):
+    if not addr:
+        raise InvalidAddrError()
+
+    parts = multiaddr.util.split(addr)
+    if not parts:
+        raise InvalidAddrError()
+
+    ipfspart = parts[-1]
+    if ipfspart.protocols()[0].code != multiaddr.protocols.P_IPFS:
+        raise InvalidAddrError()
+
+    # make sure the /ipfs value parses as a peer.ID
+    peer_id_str = ipfspart.value_for_protocol(multiaddr.protocols.P_IPFS)
+    peer_id = id_b58_decode(peer_id_str)
+
+    # we might have received just an / ipfs part, which means there's no addr.
+    if len(parts) > 1:
+        addr = multiaddr.util.join(parts[:-1])
+
+    peer_data = PeerData()
+    peer_data.addrs = [addr]
+    peer_data.protocols = [p.code for p in addr.protocols()]
+
+    return PeerInfo(peer_id, peer_data)
+
+
+class InvalidAddrError(ValueError):
+    pass

peer/peerstore.py

@@ -42,7 +42,7 @@ class PeerStore(IPeerStore):
         peer.set_protocols(protocols)
 
     def peers(self):
-        return self.peer_map.keys()
+        return list(self.peer_map.keys())
 
     def get(self, peer_id, key):
         if peer_id in self.peer_map:

requirements.txt

@@ -4,4 +4,6 @@ pytest
 pycryptodome
 pytest-asyncio
 click
-base58
+base58
+pymultihash
+py-multiaddr

tests/libp2p/test_libp2p.py

@@ -1,11 +1,14 @@
+import multiaddr
 import pytest
 
 from libp2p.libp2p import new_node
+from peer.peerinfo import info_from_p2p_addr
+
 
 @pytest.mark.asyncio
 async def test_simple_messages():
-    node_a = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/8001/ipfs/node_a"])
-    node_b = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/8000/ipfs/node_b"])
+    node_a = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/8001"])
+    node_b = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/8000"])
 
     async def stream_handler(stream):
         while True:
@@ -19,10 +22,9 @@ async def test_simple_messages():
     node_b.set_stream_handler("/echo/1.0.0", stream_handler)
 
     # Associate the peer with local ip address (see default parameters of Libp2p())
-    node_a.get_peerstore().add_addr("node_b", "/ip4/127.0.0.1/tcp/8000", 10)
+    node_a.get_peerstore().add_addrs(node_b.get_id(), node_b.get_addrs(), 10)
 
-    print("node_a about to open stream")
-    stream = await node_a.new_stream("node_b", ["/echo/1.0.0"])
+    stream = await node_a.new_stream(node_b.get_id(), ["/echo/1.0.0"])
 
     messages = ["hello" + str(x) for x in range(10)]
     for message in messages:
@@ -36,10 +38,11 @@ async def test_simple_messages():
     # Success, terminate pending tasks.
     return
 
+
 @pytest.mark.asyncio
 async def test_double_response():
-    node_a = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/8002/ipfs/node_a"])
-    node_b = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/8003/ipfs/node_b"])
+    node_a = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/8002"])
+    node_b = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/8003"])
 
     async def stream_handler(stream):
         while True:
@@ -57,9 +60,9 @@ async def test_double_response():
     node_b.set_stream_handler("/echo/1.0.0", stream_handler)
 
     # Associate the peer with local ip address (see default parameters of Libp2p())
-    node_a.get_peerstore().add_addr("node_b", "/ip4/127.0.0.1/tcp/8003", 10)
+    node_a.get_peerstore().add_addrs(node_b.get_id(), node_b.get_addrs(), 10)
     print("node_a about to open stream")
-    stream = await node_a.new_stream("node_b", ["/echo/1.0.0"])
+    stream = await node_a.new_stream(node_b.get_id(), ["/echo/1.0.0"])
     messages = ["hello" + str(x) for x in range(10)]
     for message in messages:
         await stream.write(message.encode())
@@ -76,3 +79,26 @@ async def test_double_response():
 
     # Success, terminate pending tasks.
     return
+
+@pytest.mark.asyncio
+async def test_host_connect():
+    node_a = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/8001/"])
+    node_b = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/8000/"])
+
+    assert not node_a.get_peerstore().peers()
+
+    addr = node_b.get_addrs()[0]
+    info = info_from_p2p_addr(addr)
+    await node_a.connect(info)
+
+    assert len(node_a.get_peerstore().peers()) == 1
+
+    await node_a.connect(info)
+
+    # make sure we don't do double connection
+    assert len(node_a.get_peerstore().peers()) == 1
+
+    assert node_b.get_id() in node_a.get_peerstore().peers()
+    ma_node_b = multiaddr.Multiaddr('/ipfs/%s' % node_b.get_id().pretty())
+    for addr in node_a.get_peerstore().addrs(node_b.get_id()):
+        assert addr.encapsulate(ma_node_b) in node_b.get_addrs()

tests/peer/test_peerid.py

@@ -0,0 +1,9 @@
+from Crypto.PublicKey import RSA
+from peer.id import id_from_private_key, id_from_public_key
+
+
+def test_id_from_private_key():
+    key = RSA.generate(2048, e=65537)
+    id_from_pub = id_from_public_key(key.publickey())
+    id_from_priv = id_from_private_key(key)
+    assert id_from_pub == id_from_priv

tests/peer/test_peerinfo.py

@@ -0,0 +1,11 @@
+import multiaddr
+from peer.peerinfo import info_from_p2p_addr
+
+
+def test_info_from_p2p_addr():
+    # pylint: disable=line-too-long
+    m_addr = multiaddr.Multiaddr('/ip4/127.0.0.1/tcp/8000/ipfs/3YgLAeMKSAPcGqZkAt8mREqhQXmJT8SN8VCMN4T6ih4GNX9wvK8mWJnWZ1qA2mLdCQ')
+    info = info_from_p2p_addr(m_addr)
+    assert info.peer_id.pretty() == '3YgLAeMKSAPcGqZkAt8mREqhQXmJT8SN8VCMN4T6ih4GNX9wvK8mWJnWZ1qA2mLdCQ'
+    assert len(info.addrs) == 1
+    assert str(info.addrs[0]) == '/ip4/127.0.0.1/tcp/8000'

tests/protocol_muxer/test_protocol_muxer.py

@@ -14,8 +14,8 @@ from protocol_muxer.multiselect_client import MultiselectClientError
 async def perform_simple_test(expected_selected_protocol, \
     protocols_for_client, protocols_with_handlers, \
     node_a_port, node_b_port):
-    transport_opt_a = ["/ip4/127.0.0.1/tcp/" + str(node_a_port) + "/ipfs/node_a"]
-    transport_opt_b = ["/ip4/127.0.0.1/tcp/" + str(node_b_port) + "/ipfs/node_b"]
+    transport_opt_a = ["/ip4/127.0.0.1/tcp/" + str(node_a_port)]
+    transport_opt_b = ["/ip4/127.0.0.1/tcp/" + str(node_b_port)]
     node_a = await new_node(\
         transport_opt=transport_opt_a)
     node_b = await new_node(\
@@ -34,9 +34,9 @@ async def perform_simple_test(expected_selected_protocol, \
         node_b.set_stream_handler(protocol, stream_handler)
 
     # Associate the peer with local ip address (see default parameters of Libp2p())
-    node_a.get_peerstore().add_addr("node_b", "/ip4/127.0.0.1/tcp/" + str(node_b_port), 10)
+    node_a.get_peerstore().add_addrs(node_b.get_id(), node_b.get_addrs(), 10)
 
-    stream = await node_a.new_stream("node_b", protocols_for_client)
+    stream = await node_a.new_stream(node_b.get_id(), protocols_for_client)
     messages = ["hello" + str(x) for x in range(10)]
     for message in messages:
         await stream.write(message.encode())

transport/tcp/tcp.py

@@ -23,15 +23,12 @@ class TCP(ITransport):
             """
             _multiaddr = multiaddr
 
-            # TODO check for exceptions
-            if "ipfs" in _multiaddr.get_protocols():
-                # ipfs_id = multiaddr.get_ipfs_id()
-                _multiaddr.remove_protocol("ipfs")
-
+            _multiaddr = _multiaddr.decapsulate('/ipfs')
             self.multiaddrs.append(_multiaddr)
-            multiaddr_dict = _multiaddr.to_options()
-            coroutine = asyncio.start_server(self.handler, multiaddr_dict['host'],\
-                multiaddr_dict['port'])
+
+            coroutine = asyncio.start_server(self.handler,
+                                            _multiaddr.value_for_protocol('ip4'),
+                                            _multiaddr.value_for_protocol('tcp'))
             self.server = await coroutine
             return True
 
@@ -67,9 +64,8 @@ class TCP(ITransport):
         :param options: optional object
         :return: True if successful
         """
-        _multiaddr_dict = multiaddr.to_options()
-        host = _multiaddr_dict['host']
-        port = _multiaddr_dict['port']
+        host = multiaddr.value_for_protocol('ip4')
+        port = int(multiaddr.value_for_protocol('tcp'))
 
         reader, writer = await asyncio.open_connection(host, port)
 
@@ -79,7 +75,7 @@ class TCP(ITransport):
         """
         create listener on transport
         :param options: optional object with properties the listener must have
-        :param handler_function: a function called when a new conntion is received
+        :param handler_function: a function called when a new connection is received
         that takes a connection as argument which implements interface-connection
         :return: a listener object that implements listener_interface.py
         """