nim-codex/codex/blockexchange/network/networkpeer.nim

97 lines
2.4 KiB
Nim

## Nim-Codex
## Copyright (c) 2021 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 pkg/upraises
push: {.upraises: [].}
import pkg/chronos
import pkg/chronicles
import pkg/libp2p
import ../protobuf/blockexc
import ../../errors
logScope:
topics = "codex blockexc networkpeer"
const
MaxMessageSize = 100 * 1 shl 20 # manifest files can be big
type
ConnProvider* = proc(): Future[Connection] {.gcsafe, closure.}
RPCHandler* = proc(peer: NetworkPeer, msg: Message): Future[void] {.gcsafe.}
NetworkPeer* = ref object of RootObj
id*: PeerId
handler*: RPCHandler
sendConn: Connection
getConn: ConnProvider
proc connected*(b: NetworkPeer): bool =
not(isNil(b.sendConn)) and
not(b.sendConn.closed or b.sendConn.atEof)
proc readLoop*(b: NetworkPeer, conn: Connection) {.async.} =
if isNil(conn):
return
try:
while not conn.atEof or not conn.closed:
let
data = await conn.readLp(MaxMessageSize)
msg = Message.ProtobufDecode(data).mapFailure().tryGet()
trace "Got message for peer", peer = b.id
await b.handler(b, msg)
except CatchableError as exc:
trace "Exception in blockexc read loop", exc = exc.msg
finally:
await conn.close()
proc connect*(b: NetworkPeer): Future[Connection] {.async.} =
if b.connected:
return b.sendConn
b.sendConn = await b.getConn()
asyncSpawn b.readLoop(b.sendConn)
return b.sendConn
proc send*(b: NetworkPeer, msg: Message) {.async.} =
let conn = await b.connect()
if isNil(conn):
trace "Unable to get send connection for peer message not sent", peer = b.id
return
trace "Sending message to remote", peer = b.id
await conn.writeLp(ProtobufEncode(msg))
proc broadcast*(b: NetworkPeer, msg: Message) =
proc sendAwaiter() {.async.} =
try:
await b.send(msg)
except CatchableError as exc:
trace "Exception broadcasting message to peer", peer = b.id, exc = exc.msg
asyncSpawn sendAwaiter()
func new*(
T: type NetworkPeer,
peer: PeerId,
connProvider: ConnProvider,
rpcHandler: RPCHandler): T =
doAssert(not isNil(connProvider),
"should supply connection provider")
NetworkPeer(
id: peer,
getConn: connProvider,
handler: rpcHandler)