add on/off for network emulator

Signed-off-by: Csaba Kiraly <csaba.kiraly@gmail.com>

libp2pdht/private/eth/p2p/discoveryv5/transport.nim

@@ -20,7 +20,8 @@ const
   responseTimeout* = 4.seconds ## timeout for the response of a request-response
   ## call
 
-type
+when(true): #enable network emulator
+  type
     DatagramCallback* = proc(transp: DatagramTransport,
                             remote: TransportAddress): Future[void] {.
                         gcsafe, raises: [Defect].}
@@ -31,39 +32,39 @@ type
       function: DatagramCallback      # Receive data callback
       ingress: Deque[seq[byte]]
 
-var network = initTable[Port, DatagramTransport]()
+  var network = initTable[Port, DatagramTransport]()
 
-proc `$`*(transp: DatagramTransport): string =
+  proc `$`*(transp: DatagramTransport): string =
     $transp.local
 
-proc sendTo*[T](transp: DatagramTransport, remote: TransportAddress,
+  proc sendTo*[T](transp: DatagramTransport, remote: TransportAddress,
               msg: sink seq[T], msglen = -1) {.async.} =
-  echo "sending to ", remote
+    #echo "sending to ", remote
     {.gcsafe.}:
       network[remote.port].ingress.addLast(msg)
       # call the callback on remote
       asyncCheck network[remote.port].function(network[remote.port], transp.local)
 
 
-proc getMessage*(t: DatagramTransport,): seq[byte] {.
+  proc getMessage*(t: DatagramTransport,): seq[byte] {.
       raises: [Defect, CatchableError].} =
-  echo "getMessage "
+    #echo "getMessage "
     t.ingress.popFirst()
 
-proc close*(transp: DatagramTransport) =
+  proc close*(transp: DatagramTransport) =
     echo "close"
 
-proc closed*(transp: DatagramTransport): bool {.inline.} =
+  proc closed*(transp: DatagramTransport): bool {.inline.} =
     result = false
 
-proc closeWait*(transp: DatagramTransport) {.async.} =
+  proc closeWait*(transp: DatagramTransport) {.async.} =
     echo "closeWait "
 
-proc getUserData*[T](transp: DatagramTransport): T {.inline.} =
+  proc getUserData*[T](transp: DatagramTransport): T {.inline.} =
     ## Obtain user data stored in ``transp`` object.
     result = cast[T](transp.udata)
 
-proc newDatagramTransport*[T](cbproc: DatagramCallback,
+  proc newDatagramTransport*[T](cbproc: DatagramCallback,
                             udata: ref T,
                             local: TransportAddress = AnyAddress,
                             ): DatagramTransport {.