769 lines
28 KiB
Nim
769 lines
28 KiB
Nim
import
|
|
options, macros, algorithm,
|
|
std_shims/[macros_shim, tables_shims], chronos, chronicles,
|
|
libp2p/daemon/daemonapi, faststreams/output_stream, serialization,
|
|
ssz
|
|
|
|
export
|
|
daemonapi
|
|
|
|
type
|
|
Eth2Node* = ref object of RootObj
|
|
daemon*: DaemonAPI
|
|
peers*: Table[PeerID, Peer]
|
|
protocolStates*: seq[RootRef]
|
|
|
|
Peer* = ref object
|
|
network: Eth2Node
|
|
id: PeerID
|
|
connectionState: ConnectionState
|
|
awaitedMessages: Table[CompressedMsgId, FutureBase]
|
|
protocolStates*: seq[RootRef]
|
|
|
|
EthereumNode = Eth2Node # This alias is needed for state_helpers below
|
|
|
|
ProtocolInfoObj* = object
|
|
name*: string
|
|
messages*: seq[MessageInfo]
|
|
index*: int # the position of the protocol in the
|
|
# ordered list of supported protocols
|
|
|
|
# Private fields:
|
|
peerStateInitializer*: PeerStateInitializer
|
|
networkStateInitializer*: NetworkStateInitializer
|
|
handshake*: HandshakeStep
|
|
disconnectHandler*: DisconnectionHandler
|
|
|
|
ProtocolInfo* = ptr ProtocolInfoObj
|
|
|
|
MessageInfo* = object
|
|
name*: string
|
|
|
|
# Private fields:
|
|
thunk*: MessageHandler
|
|
libp2pProtocol: string
|
|
printer*: MessageContentPrinter
|
|
nextMsgResolver*: NextMsgResolver
|
|
|
|
CompressedMsgId = tuple
|
|
protocolIndex, msgId: int
|
|
|
|
MessageKind* = enum
|
|
msgNotification,
|
|
msgRequest,
|
|
msgResponse
|
|
|
|
PeerStateInitializer* = proc(peer: Peer): RootRef {.gcsafe.}
|
|
NetworkStateInitializer* = proc(network: EthereumNode): RootRef {.gcsafe.}
|
|
HandshakeStep* = proc(peer: Peer, handshakeStream: P2PStream): Future[void] {.gcsafe.}
|
|
DisconnectionHandler* = proc(peer: Peer): Future[void] {.gcsafe.}
|
|
MessageHandler* = proc(daemon: DaemonAPI, stream: P2PStream): Future[void] {.gcsafe.}
|
|
MessageContentPrinter* = proc(msg: pointer): string {.gcsafe.}
|
|
NextMsgResolver* = proc(msgData: SszReader, future: FutureBase) {.gcsafe.}
|
|
|
|
ConnectionState* = enum
|
|
None,
|
|
Connecting,
|
|
Connected,
|
|
Disconnecting,
|
|
Disconnected
|
|
|
|
UntypedResponse = object
|
|
peer*: Peer
|
|
stream*: P2PStream
|
|
|
|
Response*[MsgType] = distinct UntypedResponse
|
|
|
|
Bytes = seq[byte]
|
|
|
|
DisconnectionReason* = enum
|
|
BreachOfProtocol
|
|
|
|
PeerDisconnected* = object of CatchableError
|
|
reason*: DisconnectionReason
|
|
|
|
const
|
|
defaultIncomingReqTimeout = 5000
|
|
defaultOutgoingReqTimeout = 10000
|
|
|
|
var
|
|
gProtocols: seq[ProtocolInfo]
|
|
|
|
# The variables above are immutable RTTI information. We need to tell
|
|
# Nim to not consider them GcSafe violations:
|
|
template allProtocols: auto = {.gcsafe.}: gProtocols
|
|
|
|
proc disconnect*(peer: Peer) {.async.} =
|
|
if peer.connectionState notin {Disconnecting, Disconnected}:
|
|
peer.connectionState = Disconnecting
|
|
await peer.network.daemon.disconnect(peer.id)
|
|
peer.connectionState = Disconnected
|
|
peer.network.peers.del(peer.id)
|
|
|
|
template raisePeerDisconnected(msg: string, r: DisconnectionReason) =
|
|
var e = newException(PeerDisconnected, msg)
|
|
e.reason = r
|
|
raise e
|
|
|
|
proc disconnectAndRaise(peer: Peer,
|
|
reason: DisconnectionReason,
|
|
msg: string) {.async.} =
|
|
let r = reason
|
|
await peer.disconnect()
|
|
raisePeerDisconnected(msg, reason)
|
|
|
|
proc init*(node: Eth2Node) {.async.} =
|
|
node.daemon = await newDaemonApi({PSGossipSub})
|
|
node.daemon.userData = node
|
|
init node.peers
|
|
|
|
newSeq node.protocolStates, allProtocols.len
|
|
for proto in allProtocols:
|
|
if proto.networkStateInitializer != nil:
|
|
node.protocolStates[proto.index] = proto.networkStateInitializer(node)
|
|
|
|
for msg in proto.messages:
|
|
if msg.libp2pProtocol.len > 0:
|
|
await node.daemon.addHandler(@[msg.libp2pProtocol], msg.thunk)
|
|
|
|
include eth/p2p/p2p_backends_helpers
|
|
include eth/p2p/p2p_tracing
|
|
|
|
import typetraits
|
|
|
|
proc readMsg(stream: P2PStream, MsgType: type,
|
|
timeout = 10000): Future[Option[MsgType]] {.async.} =
|
|
var timeout = sleepAsync timeout
|
|
var sizePrefix: uint32
|
|
var readSizePrefix = stream.transp.readExactly(addr sizePrefix, sizeof(sizePrefix))
|
|
await readSizePrefix or timeout
|
|
if not readSizePrefix.finished: return
|
|
|
|
debug "EXPECTING MSG", msg = MsgType.name, size = sizePrefix.int
|
|
|
|
var msgBytes = newSeq[byte](sizePrefix.int + sizeof(sizePrefix))
|
|
copyMem(addr msgBytes[0], addr sizePrefix, sizeof(sizePrefix))
|
|
var readBody = stream.transp.readExactly(addr msgBytes[sizeof(sizePrefix)], sizePrefix.int)
|
|
await readBody or timeout
|
|
if not readBody.finished: return
|
|
|
|
let decoded = SSZ.decode(msgBytes, MsgType)
|
|
try:
|
|
return some(decoded)
|
|
except SerializationError:
|
|
return
|
|
|
|
proc sendMsg(peer: Peer, protocolId: string, requestBytes: Bytes) {.async} =
|
|
var stream = await peer.network.daemon.openStream(peer.id, @[protocolId])
|
|
# TODO how does openStream fail? Set a timeout here and handle it
|
|
let sent = await stream.transp.write(requestBytes)
|
|
# TODO: Should I check that `sent` is equal to the desired number of bytes
|
|
|
|
proc sendBytes(stream: P2PStream, bytes: Bytes) {.async.} =
|
|
let sent = await stream.transp.write(bytes)
|
|
# TODO: Should I check that `sent` is equal to the desired number of bytes
|
|
|
|
proc makeEth2Request(peer: Peer, protocolId: string, requestBytes: Bytes,
|
|
ResponseMsg: type,
|
|
timeout = 10000): Future[Option[ResponseMsg]] {.async.} =
|
|
var stream = await peer.network.daemon.openStream(peer.id, @[protocolId])
|
|
# TODO how does openStream fail? Set a timeout here and handle it
|
|
let sent = await stream.transp.write(requestBytes)
|
|
# TODO: Should I check that `sent` is equal to the desired number of bytes
|
|
return await stream.readMsg(ResponseMsg, timeout)
|
|
|
|
proc handshakeImpl(peer: Peer,
|
|
handshakeSendFut: Future[void],
|
|
handshakeStream: P2PStream,
|
|
timeout: int,
|
|
HandshakeType: type): Future[HandshakeType] {.async.} =
|
|
await handshakeSendFut
|
|
let response = await handshakeStream.readMsg(HandshakeType, timeout)
|
|
if response.isSome:
|
|
return response.get
|
|
else:
|
|
await peer.disconnectAndRaise(BreachOfProtocol, "Handshake not completed in time")
|
|
|
|
proc p2pStreamName(MsgType: type): string =
|
|
mixin msgProtocol, protocolInfo, msgId
|
|
MsgType.msgProtocol.protocolInfo.messages[MsgType.msgId].libp2pProtocol
|
|
|
|
macro handshake*(peer: Peer, timeout = 10000, sendCall: untyped): untyped =
|
|
let
|
|
msgName = $sendCall[0]
|
|
msgType = newDotExpr(ident"CurrentProtocol", ident(msgName))
|
|
handshakeStream = ident "handshakeStream"
|
|
handshakeImpl = bindSym "handshakeImpl"
|
|
await = ident "await"
|
|
|
|
sendCall.insert(1, handshakeStream)
|
|
|
|
result = quote do:
|
|
proc payload(peer: Peer, `handshakeStream`: P2PStream): Future[`msgType`] {.async.} =
|
|
var `handshakeStream` = `handshakeStream`
|
|
if `handshakeStream` == nil:
|
|
`handshakeStream` = `await` openStream(peer.network.daemon,
|
|
peer.id,
|
|
@[p2pStreamName(`msgType`)],
|
|
`timeout`)
|
|
return `await` `handshakeImpl`(peer, `sendCall`, `handshakeStream`, `timeout`, `msgType`)
|
|
|
|
payload(`peer`, `handshakeStream`)
|
|
|
|
proc getCompressedMsgId(MsgType: type): CompressedMsgId =
|
|
mixin msgProtocol, protocolInfo, msgId
|
|
(protocolIndex: MsgType.msgProtocol.protocolInfo.index, msgId: MsgType.msgId)
|
|
|
|
proc nextMsg*(peer: Peer, MsgType: type): Future[MsgType] =
|
|
## This procs awaits a specific P2P message.
|
|
## Any messages received while waiting will be dispatched to their
|
|
## respective handlers. The designated message handler will also run
|
|
## to completion before the future returned by `nextMsg` is resolved.
|
|
mixin msgProtocol, protocolInfo, msgId
|
|
let awaitedMsgId = getCompressedMsgId(MsgType)
|
|
let f = getOrDefault(peer.awaitedMessages, awaitedMsgId)
|
|
if not f.isNil:
|
|
return Future[MsgType](f)
|
|
|
|
newFuture result
|
|
peer.awaitedMessages[awaitedMsgId] = result
|
|
|
|
proc resolveNextMsgFutures(peer: Peer, msg: auto) =
|
|
type MsgType = type(msg)
|
|
let msgId = getCompressedMsgId(MsgType)
|
|
let future = peer.awaitedMessages.getOrDefault(msgId)
|
|
if future != nil:
|
|
Future[MsgType](future).complete msg
|
|
|
|
proc init*(T: type Peer, network: Eth2Node, id: PeerID): Peer =
|
|
new result
|
|
result.id = id
|
|
result.network = network
|
|
result.awaitedMessages = initTable[CompressedMsgId, FutureBase]()
|
|
result.connectionState = Connected
|
|
newSeq result.protocolStates, allProtocols.len
|
|
for i in 0 ..< allProtocols.len:
|
|
let proto = allProtocols[i]
|
|
if proto.peerStateInitializer != nil:
|
|
result.protocolStates[i] = proto.peerStateInitializer(result)
|
|
|
|
proc performProtocolHandshakes*(peer: Peer) {.async.} =
|
|
var subProtocolsHandshakes = newSeqOfCap[Future[void]](allProtocols.len)
|
|
for protocol in allProtocols:
|
|
if protocol.handshake != nil:
|
|
subProtocolsHandshakes.add((protocol.handshake)(peer, nil))
|
|
|
|
await all(subProtocolsHandshakes)
|
|
|
|
proc getPeer*(node: Eth2Node, peerId: PeerID): Peer =
|
|
result = node.peers.getOrDefault(peerId)
|
|
if result == nil:
|
|
result = Peer.init(node, peerId)
|
|
node.peers[peerId] = result
|
|
|
|
proc peerFromStream(daemon: DaemonAPI, stream: P2PStream): Peer =
|
|
Eth2Node(daemon.userData).getPeer(stream.peer)
|
|
|
|
template getRecipient(peer: Peer): Peer =
|
|
peer
|
|
|
|
# TODO: this should be removed eventually
|
|
template getRecipient(stream: P2PStream): P2PStream =
|
|
stream
|
|
|
|
template getRecipient(response: Response): Peer =
|
|
UntypedResponse(response).peer
|
|
|
|
proc messagePrinter[MsgType](msg: pointer): string {.gcsafe.} =
|
|
result = ""
|
|
# TODO: uncommenting the line below increases the compile-time
|
|
# tremendously (for reasons not yet known)
|
|
# result = $(cast[ptr MsgType](msg)[])
|
|
|
|
proc initProtocol(name: string,
|
|
peerInit: PeerStateInitializer,
|
|
networkInit: NetworkStateInitializer): ProtocolInfoObj =
|
|
result.name = name
|
|
result.messages = @[]
|
|
result.peerStateInitializer = peerInit
|
|
result.networkStateInitializer = networkInit
|
|
|
|
proc setEventHandlers(p: ProtocolInfo,
|
|
handshake: HandshakeStep,
|
|
disconnectHandler: DisconnectionHandler) =
|
|
p.handshake = handshake
|
|
p.disconnectHandler = disconnectHandler
|
|
|
|
proc registerMsg(protocol: ProtocolInfo,
|
|
name: string,
|
|
thunk: MessageHandler,
|
|
libp2pProtocol: string,
|
|
printer: MessageContentPrinter) =
|
|
protocol.messages.add MessageInfo(name: name,
|
|
thunk: thunk,
|
|
libp2pProtocol: libp2pProtocol,
|
|
printer: printer)
|
|
|
|
proc registerProtocol(protocol: ProtocolInfo) =
|
|
# TODO: This can be done at compile-time in the future
|
|
let pos = lowerBound(gProtocols, protocol)
|
|
gProtocols.insert(protocol, pos)
|
|
for i in 0 ..< gProtocols.len:
|
|
gProtocols[i].index = i
|
|
|
|
template libp2pProtocol*(name, version: string) {.pragma.}
|
|
|
|
proc getRequestProtoName(fn: NimNode): NimNode =
|
|
# `getCustomPragmaVal` doesn't work yet on regular nnkProcDef nodes
|
|
# (TODO: file as an issue)
|
|
|
|
let pragmas = fn.pragma
|
|
if pragmas.kind == nnkPragma and pragmas.len > 0:
|
|
for pragma in pragmas:
|
|
if pragma.len > 0 and $pragma[0] == "libp2pProtocol":
|
|
return pragma[1]
|
|
|
|
error "All stream opening procs must have the 'libp2pProtocol' pragma specified.", fn
|
|
|
|
macro p2pProtocolImpl(name: static[string],
|
|
version: static[uint],
|
|
body: untyped,
|
|
timeout: static[int] = defaultOutgoingReqTimeout,
|
|
shortName: static[string] = "",
|
|
peerState = type(nil),
|
|
networkState = type(nil)): untyped =
|
|
## The macro used to defined P2P sub-protocols. See README.
|
|
var
|
|
# XXX: deal with a Nim bug causing the macro params to be
|
|
# zero when they are captured by a closure:
|
|
defaultTimeout = timeout
|
|
protoName = name
|
|
nextId = -1
|
|
protoNameIdent = ident(protoName)
|
|
outTypes = newNimNode(nnkStmtList)
|
|
outSendProcs = newNimNode(nnkStmtList)
|
|
outRecvProcs = newNimNode(nnkStmtList)
|
|
outProcRegistrations = newNimNode(nnkStmtList)
|
|
response = ident"response"
|
|
name_openStream = newTree(nnkPostfix, ident("*"), ident"openStream")
|
|
outputStream = ident"outputStream"
|
|
currentProtocolSym = ident"CurrentProtocol"
|
|
protocol = ident(protoName & "Protocol")
|
|
peerState = verifyStateType peerState.getType
|
|
networkState = verifyStateType networkState.getType
|
|
handshake = newNilLit()
|
|
disconnectHandler = newNilLit()
|
|
Format = ident"SSZ"
|
|
Option = bindSym "Option"
|
|
UntypedResponse = bindSym "UntypedResponse"
|
|
Response = bindSym "Response"
|
|
DaemonAPI = bindSym "DaemonAPI"
|
|
P2PStream = ident "P2PStream"
|
|
# XXX: Binding the int type causes instantiation failure for some reason
|
|
# Int = bindSym "int"
|
|
Int = ident "int"
|
|
Void = ident "void"
|
|
Peer = bindSym "Peer"
|
|
writeField = bindSym "writeField"
|
|
createNetworkState = bindSym "createNetworkState"
|
|
createPeerState = bindSym "createPeerState"
|
|
getOutput = bindSym "getOutput"
|
|
messagePrinter = bindSym "messagePrinter"
|
|
initProtocol = bindSym "initProtocol"
|
|
getRecipient = bindSym "getRecipient"
|
|
peerFromStream = bindSym "peerFromStream"
|
|
makeEth2Request = bindSym "makeEth2Request"
|
|
sendMsg = bindSym "sendMsg"
|
|
sendBytes = bindSym "sendBytes"
|
|
getState = bindSym "getState"
|
|
getNetworkState = bindSym "getNetworkState"
|
|
resolveNextMsgFutures = bindSym "resolveNextMsgFutures"
|
|
|
|
proc augmentUserHandler(userHandlerProc: NimNode,
|
|
msgKind = msgNotification,
|
|
extraDefinitions: NimNode = nil) =
|
|
## Turns a regular proc definition into an async proc and adds
|
|
## the helpers for accessing the peer and network protocol states.
|
|
|
|
userHandlerProc.addPragma ident"gcsafe"
|
|
userHandlerProc.addPragma ident"async"
|
|
|
|
# We allow the user handler to use `openarray` params, but we turn
|
|
# those into sequences to make the `async` pragma happy.
|
|
for i in 1 ..< userHandlerProc.params.len:
|
|
var param = userHandlerProc.params[i]
|
|
param[^2] = chooseFieldType(param[^2])
|
|
|
|
var userHandlerDefinitions = newStmtList()
|
|
|
|
userHandlerDefinitions.add quote do:
|
|
type `currentProtocolSym` = `protoNameIdent`
|
|
|
|
if extraDefinitions != nil:
|
|
userHandlerDefinitions.add extraDefinitions
|
|
|
|
# Define local accessors for the peer and the network protocol states
|
|
# inside each user message handler proc (e.g. peer.state.foo = bar)
|
|
if peerState != nil:
|
|
userHandlerDefinitions.add quote do:
|
|
template state(p: `Peer`): `peerState` =
|
|
cast[`peerState`](`getState`(p, `protocol`))
|
|
|
|
if networkState != nil:
|
|
userHandlerDefinitions.add quote do:
|
|
template networkState(p: `Peer`): `networkState` =
|
|
cast[`networkState`](`getNetworkState`(p.network, `protocol`))
|
|
|
|
userHandlerProc.body.insert 0, userHandlerDefinitions
|
|
|
|
proc liftEventHandler(doBlock: NimNode, handlerName: string): NimNode =
|
|
## Turns a "named" do block to a regular async proc
|
|
## (e.g. onPeerConnected do ...)
|
|
result = newTree(nnkProcDef)
|
|
doBlock.copyChildrenTo(result)
|
|
result.name = genSym(nskProc, protoName & handlerName)
|
|
augmentUserHandler result
|
|
outRecvProcs.add result
|
|
|
|
proc addMsgHandler(n: NimNode, msgKind = msgNotification,
|
|
responseRecord: NimNode = nil): NimNode =
|
|
if n[0].kind == nnkPostfix:
|
|
macros.error("p2pProcotol procs are public by default. " &
|
|
"Please remove the postfix `*`.", n)
|
|
|
|
inc nextId
|
|
|
|
let
|
|
msgIdent = n.name
|
|
msgName = $n.name
|
|
|
|
var
|
|
userPragmas = n.pragma
|
|
|
|
# variables used in the sending procs
|
|
msgRecipient = ident"msgRecipient"
|
|
sendTo = ident"sendTo"
|
|
writer = ident"writer"
|
|
recordStartMemo = ident"recordStartMemo"
|
|
reqTimeout: NimNode
|
|
appendParams = newNimNode(nnkStmtList)
|
|
paramsToWrite = newSeq[NimNode](0)
|
|
msgId = newLit(nextId)
|
|
|
|
# variables used in the receiving procs
|
|
receivedMsg = ident"msg"
|
|
daemon = ident "daemon"
|
|
stream = ident "stream"
|
|
await = ident "await"
|
|
peerIdent = ident "peer"
|
|
tracing = newNimNode(nnkStmtList)
|
|
|
|
# nodes to store the user-supplied message handling proc if present
|
|
userHandlerProc: NimNode = nil
|
|
userHandlerCall: NimNode = nil
|
|
awaitUserHandler = newStmtList()
|
|
|
|
# a record type associated with the message
|
|
msgRecord = newIdentNode(msgName & "Obj")
|
|
msgRecordFields = newTree(nnkRecList)
|
|
msgRecordBody = newTree(nnkObjectTy,
|
|
newEmptyNode(),
|
|
newEmptyNode(),
|
|
msgRecordFields)
|
|
|
|
result = msgRecord
|
|
|
|
if msgKind == msgRequest:
|
|
# If the request proc has a default timeout specified, remove it from
|
|
# the signature for now so we can generate the `thunk` proc without it.
|
|
# The parameter will be added back later only for to the sender proc.
|
|
# When the timeout is not specified, we use a default one.
|
|
reqTimeout = popTimeoutParam(n)
|
|
if reqTimeout == nil:
|
|
reqTimeout = newTree(nnkIdentDefs,
|
|
ident"timeout",
|
|
Int, newLit(defaultTimeout))
|
|
|
|
if n.body.kind != nnkEmpty:
|
|
# Implement the receiving thunk proc that deserialzed the
|
|
# message parameters and calls the user proc:
|
|
userHandlerProc = n.copyNimTree
|
|
userHandlerProc.name = genSym(nskProc, msgName)
|
|
|
|
# This is the call to the user supplied handler.
|
|
# Here we add only the initial params, the rest will be added later.
|
|
userHandlerCall = newCall(userHandlerProc.name)
|
|
# When there is a user handler, it must be awaited in the thunk proc.
|
|
# Above, by default `awaitUserHandler` is set to a no-op statement list.
|
|
awaitUserHandler = newCall(await, userHandlerCall)
|
|
|
|
var extraDefs: NimNode
|
|
if msgKind == msgRequest:
|
|
# Request procs need an extra param - the stream where the response
|
|
# should be written:
|
|
userHandlerProc.params.insert(1, newIdentDefs(stream, P2PStream))
|
|
userHandlerCall.add stream
|
|
let peer = userHandlerProc.params[2][0]
|
|
extraDefs = quote do:
|
|
# Jump through some hoops to work aroung
|
|
# https://github.com/nim-lang/Nim/issues/6248
|
|
let `response` = `Response`[`responseRecord`](
|
|
`UntypedResponse`(peer: `peer`, stream: `stream`))
|
|
|
|
# Resolve the Eth2Peer from the LibP2P data received in the thunk
|
|
userHandlerCall.add peerIdent
|
|
|
|
augmentUserHandler userHandlerProc, msgKind, extraDefs
|
|
outRecvProcs.add userHandlerProc
|
|
|
|
elif msgName == "status":
|
|
awaitUserHandler = quote do:
|
|
`await` `handshake`(`peerIdent`, `stream`)
|
|
|
|
for param, paramType in n.typedParams(skip = 1):
|
|
paramsToWrite.add param
|
|
|
|
# Each message has a corresponding record type.
|
|
# Here, we create its fields one by one:
|
|
msgRecordFields.add newTree(nnkIdentDefs,
|
|
newTree(nnkPostfix, ident("*"), param), # The fields are public
|
|
chooseFieldType(paramType), # some types such as openarray
|
|
# are automatically remapped
|
|
newEmptyNode())
|
|
|
|
# If there is user message handler, we'll place a call to it by
|
|
# unpacking the fields of the received message:
|
|
if userHandlerCall != nil:
|
|
userHandlerCall.add quote do: get(`receivedMsg`).`param` # newDotExpr(newCall("get", receivedMsg), param)
|
|
|
|
when tracingEnabled:
|
|
tracing = quote do:
|
|
logReceivedMsg(`stream`.peer, `receivedMsg`.get)
|
|
|
|
let requestDataTimeout = newLit(defaultIncomingReqTimeout)
|
|
|
|
let thunkName = ident(msgName & "_thunk")
|
|
var thunkProc = quote do:
|
|
proc `thunkName`(`daemon`: `DaemonAPI`, `stream`: `P2PStream`) {.async, gcsafe.} =
|
|
var `receivedMsg` = `await` readMsg(`stream`, `msgRecord`, `requestDataTimeout`)
|
|
if `receivedMsg`.isNone:
|
|
# TODO: This peer is misbehaving, perhaps we should penalize him somehow
|
|
return
|
|
let `peerIdent` = `peerFromStream`(`daemon`, `stream`)
|
|
`tracing`
|
|
`awaitUserHandler`
|
|
`resolveNextMsgFutures`(`peerIdent`, get(`receivedMsg`))
|
|
|
|
for p in userPragmas:
|
|
thunkProc.addPragma p
|
|
|
|
outRecvProcs.add thunkProc
|
|
|
|
outTypes.add quote do:
|
|
# This is a type featuring a single field for each message param:
|
|
type `msgRecord`* = `msgRecordBody`
|
|
|
|
# Add a helper template for accessing the message type:
|
|
# e.g. p2p.hello:
|
|
template `msgIdent`*(T: type `protoNameIdent`): type = `msgRecord`
|
|
template msgId*(T: type `msgRecord`): int = `msgId`
|
|
template msgProtocol*(T: type `msgRecord`): type = `protoNameIdent`
|
|
|
|
var msgSendProc = n
|
|
let msgSendProcName = n.name
|
|
outSendProcs.add msgSendProc
|
|
|
|
# TODO: check that the first param has the correct type
|
|
msgSendProc.params[1][0] = sendTo
|
|
if nextId == 0: msgSendProc.params[1][1] = P2PStream
|
|
msgSendProc.addPragma ident"gcsafe"
|
|
|
|
# Add a timeout parameter for all request procs
|
|
case msgKind
|
|
of msgRequest:
|
|
msgSendProc.params.add reqTimeout
|
|
of msgResponse:
|
|
# A response proc must be called with a response object that originates
|
|
# from a certain request. Here we change the Peer parameter at position
|
|
# 1 to the correct strongly-typed ResponseType. The incoming procs still
|
|
# gets the normal Peer paramter.
|
|
let ResponseType = newTree(nnkBracketExpr, Response, msgRecord)
|
|
msgSendProc.params[1][1] = ResponseType
|
|
outSendProcs.add quote do:
|
|
template send*(r: `ResponseType`, args: varargs[untyped]): auto =
|
|
`msgSendProcName`(r, args)
|
|
else: discard
|
|
|
|
# We change the return type of the sending proc to a Future.
|
|
# If this is a request proc, the future will return the response record.
|
|
let rt = case msgKind
|
|
of msgRequest: newTree(nnkBracketExpr, Option, responseRecord)
|
|
of msgResponse, msgNotification: Void
|
|
msgSendProc.params[0] = newTree(nnkBracketExpr, ident("Future"), rt)
|
|
|
|
let msgBytes = ident"msgBytes"
|
|
|
|
# Make the send proc public
|
|
msgSendProc.name = newTree(nnkPostfix, ident("*"), msgSendProc.name)
|
|
|
|
let initWriter = quote do:
|
|
var `outputStream` = init OutputStream
|
|
var `writer` = init(WriterType(`Format`), `outputStream`)
|
|
var `recordStartMemo` = beginRecord(`writer`, `msgRecord`)
|
|
|
|
for param in paramsToWrite:
|
|
appendParams.add newCall(writeField, writer, newLit($param), param)
|
|
|
|
when tracingEnabled:
|
|
appendParams.add logSentMsgFields(msgRecipient, protocol, msgName, paramsToWrite)
|
|
|
|
let finalizeRequest = quote do:
|
|
endRecord(`writer`, `recordStartMemo`)
|
|
let `msgBytes` = `getOutput`(`outputStream`)
|
|
|
|
var msgProto = newLit("")
|
|
let sendCall =
|
|
if msgKind != msgResponse:
|
|
msgProto = getRequestProtoName(n)
|
|
|
|
when false:
|
|
var openStreamProc = n.copyNimTree
|
|
var openStreamProc.name = name_openStream
|
|
openStreamProc.params.insert 1, newIdentDefs(ident"T", msgRecord)
|
|
|
|
if msgKind == msgRequest:
|
|
let timeout = reqTimeout[0]
|
|
quote: `makeEth2Request`(`msgRecipient`, `msgProto`, `msgBytes`,
|
|
`responseRecord`, `timeout`)
|
|
elif nextId == 0:
|
|
quote: `sendBytes`(`sendTo`, `msgBytes`)
|
|
else:
|
|
quote: `sendMsg`(`msgRecipient`, `msgProto`, `msgBytes`)
|
|
else:
|
|
quote: `sendBytes`(`UntypedResponse`(`sendTo`).stream, `msgBytes`)
|
|
|
|
msgSendProc.body = quote do:
|
|
let `msgRecipient` = `getRecipient`(`sendTo`)
|
|
`initWriter`
|
|
`appendParams`
|
|
`finalizeRequest`
|
|
return `sendCall`
|
|
|
|
outProcRegistrations.add(
|
|
newCall(bindSym("registerMsg"),
|
|
protocol,
|
|
newLit(msgName),
|
|
thunkName,
|
|
msgProto,
|
|
newTree(nnkBracketExpr, messagePrinter, msgRecord)))
|
|
|
|
outTypes.add quote do:
|
|
# Create a type acting as a pseudo-object representing the protocol
|
|
# (e.g. p2p)
|
|
type `protoNameIdent`* = object
|
|
|
|
if peerState != nil:
|
|
outTypes.add quote do:
|
|
template State*(P: type `protoNameIdent`): type = `peerState`
|
|
|
|
if networkState != nil:
|
|
outTypes.add quote do:
|
|
template NetworkState*(P: type `protoNameIdent`): type = `networkState`
|
|
|
|
for n in body:
|
|
case n.kind
|
|
of {nnkCall, nnkCommand}:
|
|
if eqIdent(n[0], "nextID"):
|
|
discard
|
|
elif eqIdent(n[0], "requestResponse"):
|
|
# `requestResponse` can be given a block of 2 or more procs.
|
|
# The last one is considered to be a response message, while
|
|
# all preceeding ones are requests triggering the response.
|
|
# The system makes sure to automatically insert a hidden `reqId`
|
|
# parameter used to discriminate the individual messages.
|
|
block processReqResp:
|
|
if n.len == 2 and n[1].kind == nnkStmtList:
|
|
var procs = newSeq[NimNode](0)
|
|
for def in n[1]:
|
|
if def.kind == nnkProcDef:
|
|
procs.add(def)
|
|
if procs.len > 1:
|
|
let responseRecord = addMsgHandler(procs[^1],
|
|
msgKind = msgResponse)
|
|
for i in 0 .. procs.len - 2:
|
|
discard addMsgHandler(procs[i],
|
|
msgKind = msgRequest,
|
|
responseRecord = responseRecord)
|
|
|
|
# we got all the way to here, so everything is fine.
|
|
# break the block so it doesn't reach the error call below
|
|
break processReqResp
|
|
macros.error("requestResponse expects a block with at least two proc definitions")
|
|
elif eqIdent(n[0], "onPeerConnected"):
|
|
var handshakeProc = liftEventHandler(n[1], "Handshake")
|
|
handshakeProc.params.add newIdentDefs(ident"handshakeStream", P2PStream)
|
|
handshake = handshakeProc.name
|
|
elif eqIdent(n[0], "onPeerDisconnected"):
|
|
disconnectHandler = liftEventHandler(n[1], "PeerDisconnect").name
|
|
else:
|
|
macros.error(repr(n) & " is not a recognized call in P2P protocol definitions", n)
|
|
of nnkProcDef:
|
|
discard addMsgHandler(n)
|
|
|
|
of nnkCommentStmt:
|
|
discard
|
|
|
|
else:
|
|
macros.error("illegal syntax in a P2P protocol definition", n)
|
|
|
|
let peerInit = if peerState == nil: newNilLit()
|
|
else: newTree(nnkBracketExpr, createPeerState, peerState)
|
|
|
|
let netInit = if networkState == nil: newNilLit()
|
|
else: newTree(nnkBracketExpr, createNetworkState, networkState)
|
|
|
|
result = newNimNode(nnkStmtList)
|
|
result.add outTypes
|
|
result.add quote do:
|
|
# One global variable per protocol holds the protocol run-time data
|
|
var p = `initProtocol`(`protoName`, `peerInit`, `netInit`)
|
|
var `protocol` = addr p
|
|
|
|
# The protocol run-time data is available as a pseudo-field
|
|
# (e.g. `p2p.protocolInfo`)
|
|
template protocolInfo*(P: type `protoNameIdent`): ProtocolInfo = `protocol`
|
|
|
|
result.add outSendProcs, outRecvProcs, outProcRegistrations
|
|
result.add quote do:
|
|
setEventHandlers(`protocol`, `handshake`, `disconnectHandler`)
|
|
|
|
result.add newCall(bindSym("registerProtocol"), protocol)
|
|
|
|
when defined(debugP2pProtocol) or defined(debugMacros):
|
|
echo repr(result)
|
|
|
|
macro p2pProtocol*(protocolOptions: untyped, body: untyped): untyped =
|
|
let protoName = $(protocolOptions[0])
|
|
result = protocolOptions
|
|
result[0] = bindSym"p2pProtocolImpl"
|
|
result.add(newTree(nnkExprEqExpr,
|
|
ident("name"),
|
|
newLit(protoName)))
|
|
result.add(newTree(nnkExprEqExpr,
|
|
ident("body"),
|
|
body))
|
|
|
|
proc makeMessageHandler[MsgType](msgHandler: proc(msg: MsgType)): P2PPubSubCallback =
|
|
result = proc(api: DaemonAPI, ticket: PubsubTicket, msg: PubSubMessage): Future[bool] {.async.} =
|
|
msgHandler SSZ.decode(msg.data, MsgType)
|
|
return true
|
|
|
|
proc subscribe*[MsgType](node: EthereumNode,
|
|
topic: string,
|
|
msgHandler: proc(msg: MsgType)) {.async.} =
|
|
discard await node.daemon.pubsubSubscribe(topic, makeMessageHandler(msgHandler))
|
|
|
|
proc broadcast*(node: Eth2Node, topic: string, msg: auto) {.async.} =
|
|
await node.daemon.pubsubPublish(topic, SSZ.encode(msg))
|
|
|