nim-libp2p/libp2p/observedaddrmanager.nim

87 lines
3.4 KiB
Nim

# Nim-LibP2P
# Copyright (c) 2023 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.
{.push raises: [].}
import std/[sequtils, tables, sugar]
import chronos
import multiaddress, multicodec
type
## Manages observed MultiAddresses by reomte peers. It keeps track of the most observed IP and IP/Port.
ObservedAddrManager* = ref object of RootObj
observedIPsAndPorts: seq[MultiAddress]
maxSize: int
minCount: int
proc addObservation*(self:ObservedAddrManager, observedAddr: MultiAddress): bool =
## Adds a new observed MultiAddress. If the number of observations exceeds maxSize, the oldest one is removed.
if self.observedIPsAndPorts.len >= self.maxSize:
self.observedIPsAndPorts.del(0)
self.observedIPsAndPorts.add(observedAddr)
return true
proc getProtocol(self: ObservedAddrManager, observations: seq[MultiAddress], multiCodec: MultiCodec): Opt[MultiAddress] =
var countTable = toCountTable(observations)
countTable.sort()
var orderedPairs = toSeq(countTable.pairs)
for (ma, count) in orderedPairs:
let protoCode = (ma[0].flatMap(protoCode)).valueOr: continue
if protoCode == multiCodec and count >= self.minCount:
return Opt.some(ma)
return Opt.none(MultiAddress)
proc getMostObservedProtocol(self: ObservedAddrManager, multiCodec: MultiCodec): Opt[MultiAddress] =
## Returns the most observed IP address or none if the number of observations are less than minCount.
let observedIPs = collect:
for observedIp in self.observedIPsAndPorts:
observedIp[0].valueOr: continue
return self.getProtocol(observedIPs, multiCodec)
proc getMostObservedProtoAndPort(self: ObservedAddrManager, multiCodec: MultiCodec): Opt[MultiAddress] =
## Returns the most observed IP/Port address or none if the number of observations are less than minCount.
return self.getProtocol(self.observedIPsAndPorts, multiCodec)
proc getMostObservedProtosAndPorts*(self: ObservedAddrManager): seq[MultiAddress] =
## Returns the most observed IP4/Port and IP6/Port address or an empty seq if the number of observations
## are less than minCount.
var res: seq[MultiAddress]
self.getMostObservedProtoAndPort(multiCodec("ip4")).withValue(ip4):
res.add(ip4)
self.getMostObservedProtoAndPort(multiCodec("ip6")).withValue(ip6):
res.add(ip6)
return res
proc guessDialableAddr*(
self: ObservedAddrManager,
ma: MultiAddress): MultiAddress =
## Replaces the first proto value of each listen address by the corresponding (matching the proto code) most observed value.
## If the most observed value is not available, the original MultiAddress is returned.
let
maFirst = ma[0].valueOr: return ma
maRest = ma[1..^1].valueOr: return ma
maFirstProto = maFirst.protoCode().valueOr: return ma
let observedIP = self.getMostObservedProtocol(maFirstProto).valueOr: return ma
return concat(observedIP, maRest).valueOr: ma
proc `$`*(self: ObservedAddrManager): string =
## Returns a string representation of the ObservedAddrManager.
return "IPs and Ports: " & $self.observedIPsAndPorts
proc new*(
T: typedesc[ObservedAddrManager],
maxSize = 10,
minCount = 3): T =
## Creates a new ObservedAddrManager.
return T(
observedIPsAndPorts: newSeq[MultiAddress](),
maxSize: maxSize,
minCount: minCount)