feat: allow multiple handlers per topic in pubsub

libp2p/protocols/pubsub/floodsub.nim

@@ -7,8 +7,7 @@
 ## This file may not be copied, modified, or distributed except according to
 ## those terms.
 
-import sequtils, tables, options, 
-       sets, sequtils, strutils, sets
+import sequtils, tables, options, sets, strutils
 import chronos, chronicles
 import pubsub,
        pubsubpeer,
@@ -77,7 +76,8 @@ proc rpcHandler(f: FloodSub,
         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 h in f.topics[t].handler:
+              await h(t, msg.data) # trigger user provided handler
 
         # forward the message to all peers interested in it
         for p in toSendPeers:
@@ -141,10 +141,11 @@ method subscribe*(f: FloodSub,
   for p in f.peers.values:
     await f.sendSubs(p, @[topic], true)
 
-method unsubscribe*(f: FloodSub, topics: seq[string]) {.async, gcsafe.} = 
+method unsubscribe*(f: FloodSub, 
+                    topics: seq[TopicPair]) {.async, gcsafe.} = 
   await procCall PubSub(f).unsubscribe(topics)
   for p in f.peers.values:
-    await f.sendSubs(p, topics, false)
+    await f.sendSubs(p, topics.mapIt(it.topic).deduplicate(), false)
 
 proc newFloodSub*(peerInfo: PeerInfo): FloodSub = 
   new result

libp2p/protocols/pubsub/pubsub.nim

@@ -21,11 +21,14 @@ logScope:
 
 type
   TopicHandler* = proc (topic: string, 
-                        data: seq[byte]): Future[void] {.closure, gcsafe.}
+                        data: seq[byte]): 
+                        Future[void] {.closure, gcsafe.}
+
+  TopicPair* = tuple[topic: string, handler: TopicHandler]
 
   Topic* = object
     name*: string
-    handler*: TopicHandler
+    handler*: seq[TopicHandler]
 
   PubSub* = ref object of LPProtocol
     peerInfo*: PeerInfo
@@ -37,9 +40,19 @@ method subscribeToPeer*(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.} = 
+method unsubscribe*(p: PubSub,
+                    topics: seq[TopicPair]) {.base, async, gcsafe.} = 
   ## unsubscribe from a list of ``topic`` strings
-  discard
+  for t in topics:
+    for i, h in p.topics[t.topic].handler:
+      if h == t.handler:
+        p.topics[t.topic].handler.del(i)
+
+method unsubscribe*(p: PubSub, 
+                    topic: string, 
+                    handler: TopicHandler): Future[void] {.base, gcsafe.} =
+  ## unsubscribe from a ``topic`` string
+  result = p.unsubscribe(@[(topic, handler)])
 
 method subscribe*(p: PubSub,
                   topic: string,
@@ -53,7 +66,10 @@ method subscribe*(p: PubSub,
   ##               that will be triggered 
   ##               on every received message
   ##
-  p.topics[topic] = Topic(name: topic, handler: handler)
+  if not p.topics.contains(topic):
+    p.topics[topic] = Topic(name: topic)
+  
+  p.topics[topic].handler.add(handler)
 
 method publish*(p: PubSub, topic: string, data: seq[byte]) {.base, async, gcsafe.} = 
   ## publish to a ``topic``

libp2p/protocols/pubsub/pubsubpeer.nim

@@ -9,12 +9,12 @@
 
 import options
 import chronos, chronicles
-import ../../connection,
-       ../../protobuf/minprotobuf,
-       ../../peerinfo,
+import rpcmsg,
        ../../peer,
+       ../../peerinfo,
+       ../../connection,
        ../../crypto/crypto,
-       rpcmsg
+       ../../protobuf/minprotobuf
 
 logScope:
   topic = "PubSubPeer"
@@ -40,7 +40,6 @@ proc handle*(p: PubSubPeer) {.async, gcsafe.} =
       await p.handler(p, @[msg])
   except:
     error "An exception occured while processing pubsub rpc requests", exc = getCurrentExceptionMsg()
-    return
   finally:
     trace "closing connection to pubsub peer", peer = p.id
     await p.conn.close()

libp2p/protocols/pubsub/rpcmsg.nim

@@ -17,8 +17,6 @@ import ../../peerinfo,
 logScope:
   topic = "RpcMsg"
 
-const SignPrefix = "libp2p-pubsub:"
-
 type
     SubOpts* = object
       subscribe*: bool
@@ -139,27 +137,38 @@ proc decodeRpcMsg*(msg: seq[byte]): RPCMsg {.gcsafe.} =
     else: 
       raise newException(CatchableError, "message type not recognized")
 
-var prefix {.threadvar.}: seq[byte]
-proc getPreix(): var seq[byte] = 
-  if prefix.len == 0:
-    prefix = cast[seq[byte]](SignPrefix)
-  result = prefix
-
 proc sign*(peerId: PeerID, msg: Message): Message = 
   var buff = initProtoBuffer()
   encodeMessage(msg, buff)
+  # NOTE: leave as is, moving out would imply making this .threadsafe., etc...
+  let prefix = cast[seq[byte]]("libp2p-pubsub:")
   if buff.buffer.len > 0:
     result = msg
     if peerId.privateKey.isSome:
       result.signature = peerId.
                          privateKey.
                          get().
-                        sign(getPreix() & buff.buffer).
+                         sign(prefix & buff.buffer).
                          getBytes()
 
+proc verify*(peerId: PeerID, m: Message): bool =
+  if m.signature.len > 0 and m.key.len > 0:
+    var msg = m
+    msg.signature = @[]
+    msg.key = @[]
+
+    var buff = initProtoBuffer()
+    encodeMessage(msg, buff)
+
+    var remote: Signature
+    var key: PublicKey
+    if remote.init(m.signature) and key.init(m.key):
+      result = remote.verify(buff.buffer, key)
+
 proc makeMessage*(peerId: PeerID,
                   data: seq[byte],
-                  name: string): Message {.gcsafe.} = 
+                  name: string,
+                  sign: bool = true): Message {.gcsafe.} = 
   var seqno: seq[byte] = newSeq[byte](20)
   if randomBytes(addr seqno[0], 20) > 0:
     var key: seq[byte] = @[]
@@ -170,7 +179,8 @@ proc makeMessage*(peerId: PeerID,
     result = Message(fromPeer: peerId.getBytes(), 
                      data: data,
                      seqno: seqno,
-                     topicIDs: @[name], 
-                     signature: @[],
-                     key: key)
+                     topicIDs: @[name])
+    if sign:
       result = sign(peerId, result)
+
+    result.key = key

libp2p/switch.nim

@@ -266,7 +266,7 @@ proc subscribe*(s: Switch, topic: string, handler: TopicHandler): Future[void] {
   
   result = s.pubSub.get().subscribe(topic, handler)
 
-proc unsubscribe*(s: Switch, topics: seq[string]): Future[void] {.gcsafe.} = 
+proc unsubscribe*(s: Switch, topics: seq[TopicPair]): Future[void] {.gcsafe.} = 
   ## unsubscribe from topics
   if s.pubSub.isNone:
     raise newNoPubSubException()

libp2p/transports/tcptransport.nim

@@ -8,9 +8,12 @@
 ## those terms.
 
 import chronos, chronicles
-import transport, ../wire, ../connection,
-       ../multiaddress, ../connection,
-       ../multicodec, ../stream/chronosstream
+import transport,
+       ../wire,
+       ../connection,
+       ../multiaddress,
+       ../multicodec,
+       ../stream/chronosstream
 
 logScope:
   topic = "TcpTransport"
@@ -71,4 +74,6 @@ method dial*(t: TcpTransport,
   let client: StreamTransport = await connect(address)
   result = await t.connHandler(t.server, client, true)
 
-method handles*(t: TcpTransport, address: MultiAddress): bool {.gcsafe.} = true
+method handles*(t: TcpTransport, address: MultiAddress): bool {.gcsafe.} = 
+  ## TODO: implement logic to properly discriminat TCP multiaddrs
+  true

tests/test.nim

@@ -16,14 +16,17 @@ import ../libp2p/switch,
        ../libp2p/protocols/secure/secure,
        ../libp2p/protocols/secure/secio,
        ../libp2p/protocols/pubsub/pubsub,
-       ../libp2p/protocols/pubsub/floodsub
+       ../libp2p/protocols/pubsub/floodsub,
+       ../libp2p/base58
 
 type
   TestProto = ref object of LPProtocol
     switch*: Switch
 
 method init(p: TestProto) {.gcsafe.} =
-  proc handle(stream: Connection, proto: string) {.async, gcsafe.} = discard
+  proc handle(stream: Connection, proto: string) {.async, gcsafe.} = 
+    echo "IN PROTO HANDLER!!!!!!!!!!!!!!!!!!!!!!!!!!"
+    echo cast[string](await stream.readLp())
 
   p.codec = "/test/proto/1.0.0"
   p.handler = handle
@@ -34,7 +37,7 @@ proc newTestProto(switch: Switch): TestProto =
   result.init()
 
 proc main() {.async.} =
-  let ma: MultiAddress = Multiaddress.init("/ip4/127.0.0.1/tcp/30333")
+  let ma: MultiAddress = Multiaddress.init("/ip4/127.0.0.1/tcp/52521")
 
   let seckey = PrivateKey.random(RSA)
   var peerInfo: PeerInfo
@@ -48,9 +51,14 @@ proc main() {.async.} =
   let transports = @[Transport(newTransport(TcpTransport))]
   let muxers = [(MplexCodec, mplexProvider)].toTable()
   let identify = newIdentify(peerInfo)
-  # let secureManagers = @[Secure(newSecIo(seckey.getKey()))]
+  let secureManagers = [(SecioCodec, Secure(newSecio(seckey)))].toTable()
   let pubSub = some(PubSub(newFloodSub(peerInfo)))
-  let switch = newSwitch(peerInfo, transports, identify, muxers, pubSub = pubSub)
+  let switch = newSwitch(peerInfo, 
+                         transports, 
+                         identify, 
+                         muxers, 
+                         secureManagers, 
+                         pubSub)
 
   var libp2pFuts = await switch.start()
   echo "Right after start"
@@ -58,20 +66,22 @@ proc main() {.async.} =
     echo item.finished
 
   var remotePeer: PeerInfo
-  remotePeer.peerId = some(PeerID.init("QmUA1Ghihi5u3gDwEDxhbu49jU42QPbvHttZFwB6b4K5oC"))
+  remotePeer.peerId = some(PeerID.init("QmPT854SM2WqCAXm4KsYkJs1NPft64m7ubaa8mgV5Tvvqg"))
   remotePeer.addrs.add(ma)
 
   switch.mount(newTestProto(switch))
   echo "PeerID: " & peerInfo.peerId.get().pretty
   # let conn = await switch.dial(remotePeer, "/test/proto/1.0.0")
+  # await conn.writeLp(cast[seq[byte]]("Hello from nim!!"))
   await switch.subscribeToPeer(remotePeer)
 
   proc handler(topic: string, data: seq[byte]): Future[void] {.closure, gcsafe.} =
     debug "IN HANDLER"
 
-  await switch.subscribe("mytesttopic", handler)
-  # let msg = cast[seq[byte]]("hello from nim")
-  # await switch.publish("mytesttopic", msg)
+  let topic = Base58.encode(cast[seq[byte]]("chat"))
+  await switch.subscribe(topic, handler)
+  let msg = cast[seq[byte]]("hello from nim")
+  await switch.publish(topic, msg)
   # debug "published message from test"
   # TODO: for some reason the connection closes unless I do a forever loop
   await allFutures(libp2pFuts)

tests/testpubsub.nim

@@ -11,6 +11,4 @@ import unittest
 import chronos
 
 suite "PubSub":
-  test "PubSub subscribe": discard
-  test "PubSub unsubscribe": discard
-
+  test "basic FloodSub": discard