remove pubsub peer on disconnect (#212)

* remove pubsub peer on disconnect

* make sure lock is aquired

* add $

* count upgrades/dials/disconnects

libp2p/muxers/mplex/lpchannel.nim

@@ -64,6 +64,7 @@ template withWriteLock(lock: AsyncLock, body: untyped): untyped =
     await lock.acquire()
     body
   finally:
+    if not(isNil(lock)) and lock.locked:
       lock.release()
 
 template withEOFExceptions(body: untyped): untyped =

libp2p/peerinfo.nim

@@ -40,6 +40,8 @@ type
 proc id*(p: PeerInfo): string =
   p.peerId.pretty()
 
+proc `$`*(p: PeerInfo): string = p.id
+
 proc shortLog*(p: PeerInfo): auto =
   (
     id: p.id(),
@@ -58,30 +60,36 @@ template postInit(peerinfo: PeerInfo,
     peerinfo.protocols = @protocols
   peerinfo.lifefut = newFuture[void]("libp2p.peerinfo.lifetime")
 
-proc init*(p: typedesc[PeerInfo], key: PrivateKey,
+proc init*(p: typedesc[PeerInfo],
+           key: PrivateKey,
            addrs: openarray[MultiAddress] = [],
            protocols: openarray[string] = []): PeerInfo {.inline.} =
   result = PeerInfo(keyType: HasPrivate, peerId: PeerID.init(key),
                     privateKey: key)
   result.postInit(addrs, protocols)
 
-proc init*(p: typedesc[PeerInfo], peerId: PeerID,
+proc init*(p: typedesc[PeerInfo],
+           peerId: PeerID,
            addrs: openarray[MultiAddress] = [],
            protocols: openarray[string] = []): PeerInfo {.inline.} =
   result = PeerInfo(keyType: HasPublic, peerId: peerId)
   result.postInit(addrs, protocols)
 
-proc init*(p: typedesc[PeerInfo], peerId: string,
+proc init*(p: typedesc[PeerInfo],
+           peerId: string,
            addrs: openarray[MultiAddress] = [],
            protocols: openarray[string] = []): PeerInfo {.inline.} =
   result = PeerInfo(keyType: HasPublic, peerId: PeerID.init(peerId))
   result.postInit(addrs, protocols)
 
-proc init*(p: typedesc[PeerInfo], key: PublicKey,
+proc init*(p: typedesc[PeerInfo],
+           key: PublicKey,
            addrs: openarray[MultiAddress] = [],
            protocols: openarray[string] = []): PeerInfo {.inline.} =
-  result = PeerInfo(keyType: HasPublic, peerId: PeerID.init(key),
+  result = PeerInfo(keyType: HasPublic,
+                    peerId: PeerID.init(key),
                     key: some(key))
+
   result.postInit(addrs, protocols)
 
 proc close*(p: PeerInfo) {.inline.} =

libp2p/protocols/pubsub/floodsub.nim

@@ -49,6 +49,8 @@ method subscribeTopic*(f: FloodSub,
     f.floodsub[topic].excl(peerId)
 
 method handleDisconnect*(f: FloodSub, peer: PubSubPeer) {.async.} =
+  await procCall PubSub(f).handleDisconnect(peer)
+
   ## handle peer disconnects
   for t in f.floodsub.keys:
     f.floodsub[t].excl(peer.id)

libp2p/protocols/pubsub/pubsub.nim

@@ -96,15 +96,17 @@ method handleDisconnect*(p: PubSub, peer: PubSubPeer) {.async, base.} =
   ## handle peer disconnects
   if peer.id in p.peers:
     p.peers.del(peer.id)
+
   # metrics
   libp2p_pubsub_peers.dec()
 
 proc cleanUpHelper(p: PubSub, peer: PubSubPeer) {.async.} =
+  try:
     await p.cleanupLock.acquire()
+    peer.refs.dec() # decrement refcount
     if peer.refs == 0:
       await p.handleDisconnect(peer)
-
-  peer.refs.dec() # decrement refcount
+  finally:
     p.cleanupLock.release()
 
 proc getPeer(p: PubSub,
@@ -117,11 +119,12 @@ proc getPeer(p: PubSub,
   # create new pubsub peer
   let peer = newPubSubPeer(peerInfo, proto)
   trace "created new pubsub peer", peerId = peer.id
+
   # metrics
   libp2p_pubsub_peers.inc()
 
   p.peers[peer.id] = peer
-  peer.refs.inc # increment reference cound
+  peer.refs.inc # increment reference count
   peer.observers = p.observers
   result = peer
 

libp2p/switch.nim

@@ -8,7 +8,7 @@
 ## those terms.
 
 import tables, sequtils, options, strformat, sets
-import chronos, chronicles
+import chronos, chronicles, metrics
 import connection,
        transports/transport,
        multistream,
@@ -31,6 +31,11 @@ logScope:
 # and only if the channel has been secured (i.e. if a secure manager has been
 # previously provided)
 
+declareGauge(libp2p_connected_peers, "total connected peers")
+declareCounter(libp2p_dialed_peers, "dialed peers")
+declareCounter(libp2p_failed_dials, "failed dials")
+declareCounter(libp2p_failed_upgrade, "peers failed upgrade")
+
 type
     NoPubSubException = object of CatchableError
 
@@ -90,6 +95,7 @@ proc identify(s: Switch, conn: Connection): Future[PeerInfo] {.async, gcsafe.} =
 
       if info.protos.len > 0:
         result.protocols = info.protos
+
       debug "identify", info = shortLog(result)
   except IdentityInvalidMsgError as exc:
     error "identify: invalid message", msg = exc.msg
@@ -152,6 +158,7 @@ proc cleanupConn(s: Switch, conn: Connection) {.async, gcsafe.} =
 
       s.dialedPubSubPeers.excl(id)
 
+      libp2p_connected_peers.dec()
       # TODO: Investigate cleanupConn() always called twice for one peer.
       if not(conn.peerInfo.isClosed()):
         conn.peerInfo.close()
@@ -245,17 +252,27 @@ proc internalConnect(s: Switch,
       for a in peer.addrs: # for each address
         if t.handles(a):   # check if it can dial it
           trace "Dialing address", address = $a
+          try:
             conn = await t.dial(a)
+            libp2p_dialed_peers.inc()
+          except CatchableError as exc:
+            trace "dialing failed", exc = exc.msg
+            libp2p_failed_dials.inc()
+            continue
+
           # make sure to assign the peer to the connection
           conn.peerInfo = peer
+
           conn = await s.upgradeOutgoing(conn)
           if isNil(conn):
+            libp2p_failed_upgrade.inc()
             continue
 
           conn.closeEvent.wait()
           .addCallback do(udata: pointer):
             asyncCheck s.cleanupConn(conn)
 
+          libp2p_connected_peers.inc()
           break
   else:
     trace "Reusing existing connection"
@@ -308,6 +325,7 @@ proc start*(s: Switch): Future[seq[Future[void]]] {.async, gcsafe.} =
   proc handle(conn: Connection): Future[void] {.async, closure, gcsafe.} =
     try:
       try:
+        libp2p_connected_peers.inc()
         await s.upgradeIncoming(conn) # perform upgrade on incoming connection
       finally:
         await s.cleanupConn(conn)
@@ -470,6 +488,7 @@ proc newSwitch*(peerInfo: PeerInfo,
         # try establishing a pubsub connection
         await s.subscribeToPeer(muxer.connection.peerInfo)
       except CatchableError as exc:
+        libp2p_failed_upgrade.inc()
         trace "exception in muxer handler", exc = exc.msg
       finally:
         if not(isNil(stream)):