nim-codex/codex/discovery.nim

149 lines
3.5 KiB
Nim

## Nim-Codex
## Copyright (c) 2022 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.
import std/algorithm
import pkg/chronos
import pkg/chronicles
import pkg/libp2p
import pkg/libp2p/routing_record
import pkg/libp2p/signed_envelope
import pkg/questionable
import pkg/questionable/results
import pkg/stew/shims/net
import pkg/contractabi/address as ca
import pkg/libp2pdht/discv5/protocol as discv5
import ./rng
import ./errors
export discv5
# TODO: If generics in methods had not been
# deprecated, this could have been implemented
# much more elegantly.
type
Discovery* = ref object of RootObj
protocol: discv5.Protocol
localInfo: PeerInfo
proc new*(
T: type Discovery,
localInfo: PeerInfo,
discoveryPort = 0.Port,
bootstrapNodes: seq[SignedPeerRecord] = @[],
): T =
T(
protocol: newProtocol(
localInfo.privateKey,
bindPort = discoveryPort,
record = localInfo.signedPeerRecord,
bootstrapRecords = bootstrapNodes,
rng = Rng.instance()
),
localInfo: localInfo)
proc toNodeId*(cid: Cid): NodeId =
## Cid to discovery id
##
readUintBE[256](keccak256.digest(cid.data.buffer).data)
proc toNodeId*(host: ca.Address): NodeId =
## Eth address to discovery id
##
readUintBE[256](keccak256.digest(host.toArray).data)
proc findPeer*(
d: Discovery,
peerId: PeerID): Future[?PeerRecord] {.async.} =
let
node = await d.protocol.resolve(toNodeId(peerId))
return
if node.isSome():
some(node.get().record.data)
else:
none(PeerRecord)
method find*(
d: Discovery,
cid: Cid): Future[seq[SignedPeerRecord]] {.async, base.} =
## Find block providers
##
trace "Finding providers for block", cid = $cid
without providers =?
(await d.protocol.getProviders(cid.toNodeId())).mapFailure, error:
trace "Error finding providers for block", cid = $cid, error = error.msg
return providers
method provide*(d: Discovery, cid: Cid) {.async, base.} =
## Provide a bock Cid
##
trace "Providing block", cid = $cid
let
nodes = await d.protocol.addProvider(
cid.toNodeId(),
d.localInfo.signedPeerRecord)
if nodes.len <= 0:
trace "Couldn't provide to any nodes!"
trace "Provided to nodes", nodes = nodes.len
method find*(
d: Discovery,
host: ca.Address): Future[seq[SignedPeerRecord]] {.async, base.} =
## Find host providers
##
trace "Finding providers for host", host = $host
without var providers =?
(await d.protocol.getProviders(host.toNodeId())).mapFailure, error:
trace "Error finding providers for host", host = $host, exc = error.msg
return
if providers.len <= 0:
trace "No providers found", host = $host
return
providers.sort do(a, b: SignedPeerRecord) -> int:
system.cmp[uint64](a.data.seqNo, b.data.seqNo)
return providers
method provide*(d: Discovery, host: ca.Address) {.async, base.} =
## Provide hosts
##
trace "Providing host", host = $host
let
nodes = await d.protocol.addProvider(
host.toNodeId(),
d.localInfo.signedPeerRecord)
if nodes.len > 0:
trace "Provided to nodes", nodes = nodes.len
proc start*(d: Discovery) {.async.} =
d.protocol.updateRecord(
d.localInfo.signedPeerRecord.some)
.expect("updating SPR")
d.protocol.open()
d.protocol.start()
proc stop*(d: Discovery) {.async.} =
await d.protocol.closeWait()