don't ping nodes during revalidation if they were pinged recently (#1779)

fluffy/network/wire/portal_protocol.nim

@@ -11,7 +11,7 @@
 {.push raises: [].}
 
 import
-  std/[sequtils, sets, algorithm],
+  std/[sequtils, sets, algorithm, tables],
   stew/[results, byteutils, leb128, endians2], chronicles, chronos,
   nimcrypto/hash, bearssl, ssz_serialization, metrics, faststreams,
   eth/rlp, eth/p2p/discoveryv5/[protocol, node, enr, routing_table, random2,
@@ -171,6 +171,7 @@ type
     offerQueue: AsyncQueue[OfferRequest]
     offerWorkers: seq[Future[void]]
     disablePoke: bool
+    pingTimings: Table[NodeId, chronos.Moment]
 
   PortalResult*[T] = Result[T, string]
 
@@ -476,7 +477,9 @@ proc new*(T: type PortalProtocol,
     stream: stream,
     radiusCache: RadiusCache.init(256),
     offerQueue: newAsyncQueue[OfferRequest](concurrentOffers),
-    disablePoke: config.disablePoke)
+    disablePoke: config.disablePoke,
+    pingTimings: initTable[NodeId, chronos.Moment]()
+    )
 
   proto.baseProtocol.registerTalkProtocol(@(proto.protocolId), proto).expect(
     "Only one protocol should have this id")
@@ -520,6 +523,7 @@ proc reqResponse[Request: SomeMessage, Response: SomeMessage](
   else:
     debug "Error receiving message response", error = messageResponse.error,
       srcId = dst.id, srcAddress = dst.address
+    p.pingTimings.del(dst.id)
     p.routingTable.replaceNode(dst)
 
   return messageResponse
@@ -569,6 +573,9 @@ proc ping*(p: PortalProtocol, dst: Node):
   let pongResponse = await p.pingImpl(dst)
 
   if pongResponse.isOk():
+    # Update last time we pinged this node
+    p.pingTimings[dst.id] = now(chronos.Moment)
+
     let pong = pongResponse.get()
     # TODO: This should become custom per Portal Network
     let customPayloadDecoded =
@@ -1252,15 +1259,28 @@ proc revalidateNode*(p: PortalProtocol, n: Node) {.async.} =
         if nodes.len > 0: # Normally a node should only return 1 record actually
           discard p.routingTable.addNode(nodes[0])
 
+proc getNodeForRevalidation(p: PortalProtocol): Opt[Node] =
+  let node = p.routingTable.nodeToRevalidate()
+  if node.isNil:
+    return Opt.none(Node)
+
+  let now = now(chronos.Moment)
+  let timestamp = p.pingTimings.getOrDefault(node.id, now)
+
+  if (timestamp + revalidationTimeout) <= now:
+    Opt.some(node)
+  else:
+    Opt.none(Node)
+
 proc revalidateLoop(p: PortalProtocol) {.async.} =
   ## Loop which revalidates the nodes in the routing table by sending the ping
   ## message.
   try:
     while true:
       await sleepAsync(milliseconds(p.baseProtocol.rng[].rand(revalidateMax)))
-      let n = p.routingTable.nodeToRevalidate()
-      if not n.isNil:
-        asyncSpawn p.revalidateNode(n)
+      let n = getNodeForRevalidation(p)
+      if n.isSome:
+        asyncSpawn p.revalidateNode(n.get())
   except CancelledError:
     trace "revalidateLoop canceled"
 

fluffy/network/wire/portal_protocol_config.nim

@@ -10,6 +10,7 @@
 import
   std/strutils,
   confutils,
+  chronos,
   eth/p2p/discoveryv5/routing_table
 
 type
@@ -29,10 +30,12 @@ type
     radiusConfig*: RadiusConfig
     disablePoke*: bool
 
+
 const
   defaultRadiusConfig* = RadiusConfig(kind: Dynamic)
   defaultRadiusConfigDesc* = $defaultRadiusConfig.kind
   defaultDisablePoke* = false
+  revalidationTimeout* = chronos.seconds(30) 
 
   defaultPortalProtocolConfig* = PortalProtocolConfig(
     tableIpLimits: DefaultTableIpLimits,