wip: floodsub initial implementation

chronos

@@ -0,0 +1 @@
+Subproject commit 7029f8bc1e98e6b4360ffcfe37e1602cf25fd6c8

libp2p/peer.nim

@@ -21,7 +21,7 @@ const
 type
   PeerID* = object
     data*: seq[byte]
-    privateKey: PrivateKey
+    privateKey*: PrivateKey
     publicKey: PublicKey
 
   PeerIDError* = object of CatchableError

libp2p/protocols/identify.nim

@@ -68,7 +68,7 @@ proc decodeMsg*(buf: seq[byte]): IdentifyInfo =
 
   result.addrs = newSeq[MultiAddress]()
   var address = newSeq[byte]()
-  while pb.getBytes(2, address) != -1:
+  while pb.getBytes(2, address) > 0:
     if len(address) != 0:
       var copyaddr = address
       result.addrs.add(MultiAddress.init(copyaddr))

libp2p/protocols/pubsub/floodsub.nim

@@ -7,47 +7,129 @@
 ## This file may not be copied, modified, or distributed except according to
 ## those terms.
 
+import sequtils, tables, options, sets
 import chronos, chronicles
-import ../protocol,
-       ../../connection
+import pubsub,
+       pubsubpeer,
+       rpcmsg,
+       ../../connection,
+       ../../peerinfo,
+       ../../peer
 
 logScope:
-  topic = "floodsub"
+  topic = "FloodSub"
 
 const FloodSubCodec* = "/floodsub/1.0.0"
 
 type
-  TopicHandler* = proc(topic:string, data: seq[byte]): Future[void] {.gcsafe.}
-  Topic* = object
-    name*: string
-    handler*: TopicHandler
+  FloodSub = ref object of PubSub
 
-  Peer* = object
-    conn: Connection
-    topics: string
+proc sendSubs(f: FloodSub,
+              peer: PubSubPeer,
+              topics: seq[string],
+              subscribe: bool)
+              {.async, gcsafe.} =
+  ## send subscriptions to remote peer
+  var msg: RPCMsg
+  for t in topics:
+    msg.subscriptions.add(SubOpts(topic: t, subscribe: subscribe))
 
-  FloodSub* = ref object of LPProtocol
-    topics: seq[Topic]
-    peers: seq[Peer]
+  await peer.send(@[msg])
 
-proc encodeRpcMsg() = discard
-proc decodeRpcMsg() = discard
+proc rpcHandler(f: FloodSub,
+                peer: PubSubPeer,
+                rpcMsgs: seq[RPCMsg])
+                {.async, gcsafe.} =
+  ## method called by a PubSubPeer every 
+  ## time it receives an RPC message
+  ##
+  ## The RPC message might contain subscriptions 
+  ## or messages forwarded to this peer
+  ##
 
-method init*(f: FloodSub) = 
+  for m in rpcMsgs:                                # for all RPC messages
+    if m.subscriptions.len > 0:                    # if there are any subscriptions
+      for s in m.subscriptions:                    # subscribe/unsubscribe the peer for each topic
+        let id = peer.conn.peerInfo.get().peerId.pretty
+        if s.subscribe:
+          # subscribe the peer to the topic
+          f.peerTopics[s.topic].incl(id)
+        else:
+          # unsubscribe the peer to the topic
+          f.peerTopics[s.topic].excl(id)
+
+      # send subscriptions to every peer
+      for p in f.peers.values:
+        await p.send(@[RPCMsg(subscriptions: m.subscriptions)])
+
+    if m.messages.len > 0:                         # if there are any messages
+      var toSendPeers: HashSet[string]
+      for msg in m.messages:                       # for every message
+        for t in msg.topicIDs:                     # for every topic in the message
+          toSendPeers.incl(f.peerTopics[t])        # get all the peers interested in this topic
+          if f.topics.contains(t):                 # check that we're subscribed to it
+            await f.topics[t].handler(t, msg.data) # trigger user provided handler
+
+        for p in toSendPeers:
+          await f.peers[p].send(@[RPCMsg(messages: m.messages)])
+
+proc handleConn(f: FloodSub, conn: Connection) {.async, gcsafe.} = 
+  ## handle incoming/outgoing connections
+  ##
+  ## this proc will:
+  ## 1) register a new PubSubPeer for the connection
+  ## 2) register a handler with the peer;
+  ##    this handler gets called on every rpc message 
+  ##    that the peer receives
+  ## 3) ask the peer to subscribe us to every topic 
+  ##    that we're interested in
+  ## 
+
+  proc handleRpc(peer: PubSubPeer, msgs: seq[RPCMsg]) {.async, gcsafe.} =
+    await f.rpcHandler(peer, msgs)
+
+  var peer = newPubSubPeer(conn, handleRpc)
+  f.peers[peer.conn.peerInfo.get().peerId.pretty()] = peer
+  let topics = toSeq(f.topics.keys)
+  await f.sendSubs(peer, topics, true)
+  asyncCheck peer.handle()
+
+method init(f: FloodSub) = 
   proc handler(conn: Connection, proto: string) {.async, gcsafe.} = 
-    discard
+    ## main protocol handler that gets triggered on every 
+    ## connection for a protocol string
+    ## e.g. ``/floodsub/1.0.0``, etc...
+    ##
+
+    await f.handleConn(conn)
 
-  f.codec = FloodSubCodec
   f.handler = handler
+  f.codec = FloodSubCodec
+
+method subscribePeer*(f: FloodSub, conn: Connection) {.async, gcsafe.} =
+  await f.handleConn(conn)
+
+method publish*(f: FloodSub,
+                topic: string,
+                data: seq[byte])
+                {.async, gcsafe.} = 
+  for p in f.peerTopics[topic]:
+    f.peers[p].send(Message(fromPeer: f.peerInfo.peerId.data, 
+                            data: data))
 
 method subscribe*(f: FloodSub, 
                   topic: string, 
-                  handler: TopicHandler) 
-                  {.base, async, gcsafe.} = 
-  discard
+                  handler: TopicHandler)
+                  {.async, gcsafe.} = 
+  await procCall PubSub(f).subscribe(topic, handler)
+  for p in f.peers.values:
+    await f.sendSubs(p, @[topic], true)
 
-method publish*(f: FloodSub, topic: string) {.base, async, gcsafe.} = 
-  discard
+method unsubscribe*(f: FloodSub, topics: seq[string]) {.async, gcsafe.} = 
+  await procCall PubSub(f).unsubscribe(topics)
+  for p in f.peers.values:
+    await f.sendSubs(p, topics, false)
 
-proc newFloodSub*(): FloodSub = 
+proc newFloodSub*(peerInfo: PeerInfo): FloodSub = 
   new result
+  result.peerInfo = peerInfo

libp2p/protocols/pubsub/pubsub.nim

@@ -0,0 +1,55 @@
+## Nim-LibP2P
+## Copyright (c) 2018 Status Research & Development GmbH
+## Licensed under either of
+##  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
+##  * MIT license ([LICENSE-MIT](LICENSE-MIT))
+## at your option.
+## This file may not be copied, modified, or distributed except according to
+## those terms.
+
+import tables, sets
+import chronos
+import pubsubpeer,
+       ../protocol,
+       ../../connection,
+       ../../peerinfo
+
+export PubSubPeer
+
+type
+  TopicHandler* = proc(topic:string, data: seq[byte]): Future[void] {.gcsafe.}
+  Topic* = object
+    name*: string
+    handler*: TopicHandler
+
+  PubSub* = ref object of LPProtocol
+    peerInfo*: PeerInfo
+    topics*: Table[string, Topic] # local topics
+    peers*: Table[string, PubSubPeer] # peerid to peer map
+    peerTopics*: Table[string, HashSet[string]] # topic to remote peer map
+
+method subscribePeer*(p: PubSub, conn: Connection) {.base, async, gcsafe.} =
+  ## subscribe to a peer to send/receive pubsub messages
+  discard
+
+method unsubscribe*(p: PubSub, topics: seq[string]) {.base, async, gcsafe.} = 
+  ## unsubscribe from a list of ``topic`` strings
+  discard
+
+method subscribe*(p: PubSub, 
+                  topic: string, 
+                  handler: TopicHandler)
+                  {.base, async, gcsafe.} = 
+  ## subscribe to a topic
+  ##
+  ## ``topic``   - a string topic to subscribe to
+  ##
+  ## ``handler`` - is a user provided proc 
+  ##               that will be triggered 
+  ##               on every received message
+  ##
+  p.topics[topic] = Topic(name: topic, handler: handler)
+
+method publish*(p: PubSub, topic: string, data: seq[byte]) {.base, async, gcsafe.} = 
+  ## publish to a ``topic``
+  discard

libp2p/protocols/pubsub/pubsubpeer.nim

@@ -0,0 +1,46 @@
+## Nim-LibP2P
+## Copyright (c) 2018 Status Research & Development GmbH
+## Licensed under either of
+##  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
+##  * MIT license ([LICENSE-MIT](LICENSE-MIT))
+## at your option.
+## This file may not be copied, modified, or distributed except according to
+## those terms.
+
+import options
+import chronos, chronicles
+import ../../connection,
+       ../../protobuf/minprotobuf,
+       ../../peerinfo,
+       rpcmsg
+
+logScope:
+  topic = "PubSubPeer"
+
+type
+    PubSubPeer* = ref object of RootObj
+      conn*: Connection
+      handler*: RPCHandler
+      topics*: seq[string]
+
+    RPCHandler* = proc(peer: PubSubPeer, msg: seq[RPCMsg]): Future[void] {.gcsafe.}
+
+proc handle*(p: PubSubPeer) {.async, gcsafe.} =
+  try:
+    while not p.conn.closed:
+      let msg = decodeRpcMsg(await p.conn.readLp())
+      await p.handler(p, @[msg])
+  except:
+    debug "An exception occured while processing pubsub rpc requests", exc = getCurrentExceptionMsg()
+    return
+  finally:
+    await p.conn.close()
+
+proc send*(p: PubSubPeer, msgs: seq[RPCMsg]) {.async, gcsafe.} =
+  for m in msgs:
+    await p.conn.writeLp(encodeRpcMsg(m).buffer)
+
+proc newPubSubPeer*(conn: Connection, handler: RPCHandler): PubSubPeer =
+  new result
+  result.handler = handler
+  result.conn = conn

libp2p/protocols/pubsub/rpcmsg.nim

@@ -0,0 +1,138 @@
+## Nim-LibP2P
+## Copyright (c) 2018 Status Research & Development GmbH
+## Licensed under either of
+##  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
+##  * MIT license ([LICENSE-MIT](LICENSE-MIT))
+## at your option.
+## This file may not be copied, modified, or distributed except according to
+## those terms.
+
+import sequtils
+import chronos, nimcrypto/sysrand
+import ../../peerinfo, 
+       ../../peer,
+       ../../crypto/crypto,
+       ../../protobuf/minprotobuf
+
+const SignPrefix = "libp2p-pubsub:"
+
+type
+    SubOpts* = object
+      subscribe*: bool
+      topic*: string
+
+    Message* = object
+      fromPeer*: seq[byte]
+      data*: seq[byte]
+      seqno*: seq[byte]
+      topicIDs*: seq[string]
+      signature*: seq[byte]
+      key*: seq[byte]
+
+    RPCMsg* = object
+      subscriptions*: seq[SubOpts]
+      messages*: seq[Message]
+
+proc encodeMessage(msg: Message, buff: var ProtoBuffer) {.gcsafe.} = 
+  buff.write(initProtoField(1, msg.fromPeer))
+  buff.write(initProtoField(2, msg.data))
+  buff.write(initProtoField(3, msg.seqno))
+
+  for t in msg.topicIDs:
+    buff.write(initProtoField(4, t))
+
+  buff.write(initProtoField(5, msg.signature))
+  buff.write(initProtoField(6, msg.key))
+
+  buff.finish()
+
+proc encodeSubs(subs: SubOpts, buff: var ProtoBuffer) {.gcsafe.} = 
+  buff.write(initProtoField(1, ord(subs.subscribe)))
+  buff.write(initProtoField(2, subs.topic))
+
+proc encodeRpcMsg*(msg: RPCMsg): ProtoBuffer {.gcsafe.} = 
+  result = initProtoBuffer({WithVarintLength})
+
+  var subs = initProtoBuffer()
+  for s in msg.subscriptions:
+    encodeSubs(s, subs)
+
+  subs.finish()
+  result.write(initProtoField(1, subs))
+
+  var messages = initProtoBuffer()
+  for m in msg.messages:
+    encodeMessage(m, messages)
+
+  messages.finish()
+  result.write(initProtoField(2, messages))
+
+  result.finish()
+
+proc decodeRpcMsg*(msg: seq[byte]): RPCMsg {.gcsafe.} = 
+  var pb = initProtoBuffer(msg)
+  
+  result.subscriptions = newSeq[SubOpts]()
+  var subscr = newSeq[byte](1)
+
+  # decode SubOpts array
+  if pb.enterSubMessage() > 0:
+    while true:
+      var subOpt: SubOpts
+      if pb.getBytes(1, subscr) < 0:
+        break
+      subOpt.subscribe = cast[bool](subscr)
+      
+      if pb.getString(2, subOpt.topic) < 0:
+        break
+      result.subscriptions.add(subOpt)
+
+  result.messages = newSeq[Message]()
+  # TODO: which of this fields are really optional?
+  # Decode Messages array
+  if pb.enterSubMessage() > 0:
+    while true:
+      var msg: Message
+      if pb.getBytes(1, msg.fromPeer) < 0:
+        break
+
+      if pb.getBytes(2, msg.data) < 0:
+        break
+      
+      if pb.getBytes(3, msg.seqno) < 0:
+        break
+
+      var topic: string
+      while true:
+        if pb.getString(4, topic) < 0:
+          break
+        topic.add(topic)
+        topic = ""
+      
+      if pb.getBytes(5, msg.signature) < 0:
+        break
+
+      if pb.getBytes(6, msg.key) < 0:
+        break
+
+proc sign*(peerId: PeerID, msg: Message): Message = 
+  var buff = initProtoBuffer()
+  var prefix = cast[seq[byte]](toSeq(SignPrefix.items)) # TODO: can we cache this?
+  encodeMessage(msg, buff)
+  if buff.buffer.len > 0:
+    result = msg
+    result.signature = peerId.
+                       privateKey.
+                       sign(prefix & buff.buffer).
+                       getBytes()
+
+proc makeMessage*(peerId: PeerID, data: seq[byte], name: string): Message = 
+  var seqno: seq[byte] = newSeq[byte](20)
+  if randomBytes(addr seqno[0], 20) > 0:
+    result = Message(fromPeer: peerId.getBytes(), 
+                     data: data, 
+                     seqno: seqno, 
+                     topicIDs: @[name], 
+                     signature: @[],
+                     key: peerId.publicKey.getRawBytes())
+    result = sign(peerId, result)

tests/test.nim

@@ -0,0 +1,65 @@
+import tables
+import chronos, chronicles
+import ../libp2p/switch, 
+       ../libp2p/multistream,
+       ../libp2p/protocols/identify, 
+       ../libp2p/connection,
+       ../libp2p/transports/[transport, tcptransport], 
+       ../libp2p/multiaddress, 
+       ../libp2p/peerinfo,
+       ../libp2p/crypto/crypto, 
+       ../libp2p/peer,
+       ../libp2p/protocols/protocol, 
+       ../libp2p/muxers/muxer,
+       ../libp2p/muxers/mplex/mplex, 
+       ../libp2p/muxers/mplex/types,
+       ../libp2p/protocols/secure/secure,
+       ../libp2p/protocols/secure/secio
+
+type
+  TestProto = ref object of LPProtocol
+
+method init(p: TestProto) {.gcsafe.} =
+  proc handle(stream: Connection, proto: string) {.async, gcsafe.} = 
+    await stream.writeLp("Hello from handler")
+    await stream.close()
+
+  p.codec = "/test/proto/1.0.0"
+  p.handler = handle
+
+proc newTestProto(): TestProto = 
+  new result
+  result.init()
+
+proc main() {.async.} =
+  let ma: MultiAddress = Multiaddress.init("/ip4/127.0.0.1/tcp/30333")
+
+  let seckey = PrivateKey.random(RSA)
+  var peerInfo: PeerInfo
+  peerInfo.peerId = PeerID.init(seckey)
+  peerInfo.addrs.add(Multiaddress.init("/ip4/127.0.0.1/tcp/55055"))
+
+  proc createMplex(conn: Connection): Muxer =
+    result = newMplex(conn)
+
+  let mplexProvider = newMuxerProvider(createMplex, MplexCodec)
+  let transports = @[Transport(newTransport(TcpTransport))]
+  let muxers = [(MplexCodec, mplexProvider)].toTable()
+  let identify = newIdentify(peerInfo)
+  let switch = newSwitch(peerInfo, transports, identify, muxers, @[Secure(newSecIo(seckey.getKey()))])
+
+  await switch.start()
+
+  var remotePeer: PeerInfo
+  remotePeer.peerId = PeerID.init("QmUA1Ghihi5u3gDwEDxhbu49jU42QPbvHttZFwB6b4K5oC")
+  remotePeer.addrs.add(ma)
+
+  switch.mount(newTestProto())
+  echo "PeerID: " & peerInfo.peerId.pretty
+  let conn = await switch.dial(remotePeer, "/test/proto/1.0.0")
+  await conn.writeLp("Hello from dialer!")
+  let msg = cast[string](await conn.readLp())
+  echo msg
+  await conn.close()
+
+waitFor(main())

tests/testpubsub.nim

@@ -0,0 +1,16 @@
+## Nim-Libp2p
+## Copyright (c) 2018 Status Research & Development GmbH
+## Licensed under either of
+##  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
+##  * MIT license ([LICENSE-MIT](LICENSE-MIT))
+## at your option.
+## This file may not be copied, modified, or distributed except according to
+## those terms.
+
+import unittest
+import chronos
+
+suite "PubSub":
+  test "PubSub subscribe": discard
+  test "PubSub unsubscribe": discard
+

tests/testsecio.nim

@@ -0,0 +1,2 @@
+import unittest
+