nim-libp2p/libp2p/protocols/pubsub/floodsub.nim

157 lines
5.5 KiB
Nim
Raw Normal View History

2019-09-10 02:14:24 +00:00
## Nim-LibP2P
2019-09-24 17:48:23 +00:00
## Copyright (c) 2019 Status Research & Development GmbH
2019-09-10 02:14:24 +00:00
## 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 sequtils, tables, options, sets, strutils
2019-09-10 02:14:24 +00:00
import chronos, chronicles
2019-09-10 02:15:52 +00:00
import pubsub,
pubsubpeer,
rpcmsg,
../../connection,
../../peerinfo,
../../peer
2019-09-10 02:14:24 +00:00
logScope:
2019-09-10 02:15:52 +00:00
topic = "FloodSub"
2019-09-10 02:14:24 +00:00
const FloodSubCodec* = "/floodsub/1.0.0"
type
2019-09-10 02:15:52 +00:00
FloodSub = ref object of PubSub
2019-09-10 02:14:24 +00:00
2019-09-10 02:15:52 +00:00
proc sendSubs(f: FloodSub,
peer: PubSubPeer,
topics: seq[string],
subscribe: bool) {.async, gcsafe.} =
2019-09-10 02:15:52 +00:00
## send subscriptions to remote peer
trace "sending subscriptions", peer = peer.id, subscribe = subscribe
2019-09-10 02:15:52 +00:00
var msg: RPCMsg
for t in topics:
trace "sending topic", peer = peer.id, subscribe = subscribe, topicName = t
2019-09-10 02:15:52 +00:00
msg.subscriptions.add(SubOpts(topic: t, subscribe: subscribe))
2019-09-10 02:14:24 +00:00
2019-09-10 02:15:52 +00:00
await peer.send(@[msg])
2019-09-10 02:14:24 +00:00
2019-09-10 02:15:52 +00:00
proc rpcHandler(f: FloodSub,
peer: PubSubPeer,
rpcMsgs: seq[RPCMsg]) {.async, gcsafe.} =
## method called by a PubSubPeer every
2019-09-10 02:15:52 +00:00
## time it receives an RPC message
##
## The RPC message might contain subscriptions
2019-09-10 02:15:52 +00:00
## or messages forwarded to this peer
##
2019-09-10 02:14:24 +00:00
trace "processing RPC message", peer = peer.id, msg = rpcMsgs
2019-09-10 02:15:52 +00:00
for m in rpcMsgs: # for all RPC messages
trace "processing message", msg = rpcMsgs
2019-09-10 02:15:52 +00:00
if m.subscriptions.len > 0: # if there are any subscriptions
for s in m.subscriptions: # subscribe/unsubscribe the peer for each topic
2019-09-12 02:10:38 +00:00
let id = peer.id
2019-09-12 05:46:08 +00:00
if not f.peerTopics.contains(s.topic):
f.peerTopics[s.topic] = initSet[string]()
2019-09-10 02:15:52 +00:00
if s.subscribe:
trace "subscribing to topic", peer = id, subscriptions = m.subscriptions, topic = s.topic
2019-09-10 02:15:52 +00:00
# subscribe the peer to the topic
f.peerTopics[s.topic].incl(id)
else:
trace "unsubscribing to topic", peer = id, subscriptions = m.subscriptions, topic = s.topic
2019-09-12 10:08:11 +00:00
# unsubscribe the peer from the topic
2019-09-10 02:15:52 +00:00
f.peerTopics[s.topic].excl(id)
# send subscriptions to every peer
for p in f.peers.values:
await p.send(@[RPCMsg(subscriptions: m.subscriptions)])
2019-09-12 10:08:11 +00:00
var toSendPeers: HashSet[string] = initSet[string]()
2019-09-10 02:15:52 +00:00
if m.messages.len > 0: # if there are any messages
for msg in m.messages: # for every message
for t in msg.topicIDs: # for every topic in the message
toSendPeers.incl(f.peerTopics[t]) # get all the peers interested in this topic
if f.topics.contains(t): # check that we're subscribed to it
for h in f.topics[t].handler:
await h(t, msg.data) # trigger user provided handler
2019-09-10 02:15:52 +00:00
2019-09-14 13:56:02 +00:00
# forward the message to all peers interested in it
2019-09-10 02:15:52 +00:00
for p in toSendPeers:
await f.peers[p].send(@[RPCMsg(messages: m.messages)])
2019-09-12 10:08:11 +00:00
proc handleConn(f: FloodSub,
conn: Connection) {.async, gcsafe.} =
2019-09-10 02:15:52 +00:00
## handle incoming/outgoing connections
##
## this proc will:
## 1) register a new PubSubPeer for the connection
## 2) register a handler with the peer;
## this handler gets called on every rpc message
## that the peer receives
## 3) ask the peer to subscribe us to every topic
## that we're interested in
##
proc handleRpc(peer: PubSubPeer, msgs: seq[RPCMsg]) {.async, gcsafe.} =
await f.rpcHandler(peer, msgs)
var peer = newPubSubPeer(conn, handleRpc)
2019-09-12 02:10:38 +00:00
if peer.peerInfo.peerId.isNone:
debug "no valid PeerInfo for peer"
return
f.peers[peer.id] = peer
2019-09-10 02:15:52 +00:00
let topics = toSeq(f.topics.keys)
await f.sendSubs(peer, topics, true)
asyncCheck peer.handle()
method init(f: FloodSub) =
2019-09-12 10:08:11 +00:00
proc handler(conn: Connection, proto: string) {.async, gcsafe.} =
## main protocol handler that gets triggered on every
2019-09-10 02:15:52 +00:00
## connection for a protocol string
## e.g. ``/floodsub/1.0.0``, etc...
##
await f.handleConn(conn)
2019-09-10 02:14:24 +00:00
f.handler = handler
2019-09-10 02:15:52 +00:00
f.codec = FloodSubCodec
2019-09-12 02:10:38 +00:00
method subscribeToPeer*(f: FloodSub, conn: Connection) {.async, gcsafe.} =
2019-09-10 02:15:52 +00:00
await f.handleConn(conn)
method publish*(f: FloodSub,
topic: string,
data: seq[byte]) {.async, gcsafe.} =
trace "about to publish message on topic", topic = topic, data = data
2019-09-12 02:10:38 +00:00
let msg = makeMessage(f.peerInfo.peerId.get(), data, topic)
if topic in f.peerTopics:
for p in f.peerTopics[topic]:
trace "pubslishing message", topic = topic, peer = p, data = data
2019-09-12 02:10:38 +00:00
await f.peers[p].send(@[RPCMsg(messages: @[msg])])
2019-09-10 02:14:24 +00:00
2019-09-12 10:08:11 +00:00
method subscribe*(f: FloodSub,
topic: string,
handler: TopicHandler) {.async, gcsafe.} =
2019-09-10 02:15:52 +00:00
await procCall PubSub(f).subscribe(topic, handler)
for p in f.peers.values:
await f.sendSubs(p, @[topic], true)
2019-09-10 02:14:24 +00:00
method unsubscribe*(f: FloodSub,
topics: seq[TopicPair]) {.async, gcsafe.} =
2019-09-10 02:15:52 +00:00
await procCall PubSub(f).unsubscribe(topics)
for p in f.peers.values:
await f.sendSubs(p, topics.mapIt(it.topic).deduplicate(), false)
2019-09-10 02:14:24 +00:00
2019-09-10 02:15:52 +00:00
proc newFloodSub*(peerInfo: PeerInfo): FloodSub =
2019-09-10 02:14:24 +00:00
new result
2019-09-10 02:15:52 +00:00
result.peerInfo = peerInfo
2019-09-12 02:10:38 +00:00
result.peers = initTable[string, PubSubPeer]()
result.topics = initTable[string, Topic]()
result.peerTopics = initTable[string, HashSet[string]]()
result.init()