Refactored the p2pProtocol macro to eliminate most code duplication in the backends

eth/p2p/p2p_backends_helpers.nim

@@ -1,4 +1,4 @@
-proc getState(peer: Peer, proto: ProtocolInfo): RootRef =
+proc getState*(peer: Peer, proto: ProtocolInfo): RootRef =
   peer.protocolStates[proto.index]
 
 template state*(peer: Peer, Protocol: type): untyped =
@@ -8,7 +8,7 @@ template state*(peer: Peer, Protocol: type): untyped =
   bind getState
   cast[Protocol.State](getState(peer, Protocol.protocolInfo))
 
-proc getNetworkState(node: EthereumNode, proto: ProtocolInfo): RootRef =
+proc getNetworkState*(node: EthereumNode, proto: ProtocolInfo): RootRef =
   node.protocolStates[proto.index]
 
 template protocolState*(node: EthereumNode, Protocol: type): untyped =
@@ -23,44 +23,6 @@ template networkState*(connection: Peer, Protocol: type): untyped =
 
 proc initProtocolState*[T](state: T, x: Peer|EthereumNode) {.gcsafe.} = discard
 
-proc createPeerState[ProtocolState](peer: Peer): RootRef =
-  var res = new ProtocolState
-  mixin initProtocolState
-  initProtocolState(res, peer)
-  return cast[RootRef](res)
-
-proc createNetworkState[NetworkState](network: EthereumNode): RootRef {.gcsafe.} =
-  var res = new NetworkState
-  mixin initProtocolState
-  initProtocolState(res, network)
-  return cast[RootRef](res)
-
-proc chooseFieldType(n: NimNode): NimNode =
-  ## Examines the parameter types used in the message signature
-  ## and selects the corresponding field type for use in the
-  ## message object type (i.e. `p2p.hello`).
-  ##
-  ## For now, only openarray types are remapped to sequences.
-  result = n
-  if n.kind == nnkBracketExpr and eqIdent(n[0], "openarray"):
-    result = n.copyNimTree
-    result[0] = ident("seq")
-
-proc popTimeoutParam(n: NimNode): NimNode =
-  var lastParam = n.params[^1]
-  if eqIdent(lastParam[0], "timeout"):
-    if lastParam[2].kind == nnkEmpty:
-      macros.error "You must specify a default value for the `timeout` parameter", lastParam
-    result = lastParam
-    n.params.del(n.params.len - 1)
-
-proc verifyStateType(t: NimNode): NimNode =
-  result = t[1]
-  if result.kind == nnkSym and $result == "nil":
-    return nil
-  if result.kind != nnkBracketExpr or $result[0] != "ref":
-    macros.error($result & " must be a ref type")
-
 proc initFuture[T](loc: var Future[T]) =
   loc = newFuture[T]()
 

eth/p2p/p2p_protocol_dsl.nim

@@ -0,0 +1,554 @@
+import
+  macros,
+  std_shims/macros_shim, chronos/timer
+
+type
+  MessageKind* = enum
+    msgHandshake
+    msgNotification
+    msgRequest
+    msgResponse
+
+  Message* = ref object
+    id*: int
+    ident*: NimNode
+    kind*: MessageKind
+    procDef*: NimNode
+    timeoutParam*: NimNode
+    recIdent*: NimNode
+    recBody*: NimNode
+    userHandler*: NimNode
+
+  Request* = ref object
+    queries*: seq[Message]
+    response*: Message
+
+  P2PProtocol* = ref object
+    # Settings
+    name*: string
+    version*: int
+    timeouts*: int64
+    useRequestIds*: bool
+    shortName*: string
+    outgoingRequestDecorator*: NimNode
+    incomingRequestDecorator*: NimNode
+    incomingRequestThunkDecorator*: NimNode
+    incomingResponseDecorator*: NimNode
+    incomingResponseThunkDecorator*: NimNode
+    PeerStateType*: NimNode
+    NetworkStateType*: NimNode
+    backend*: Backend
+
+    # Cached properties
+    nameIdent*: NimNode
+    protocolInfoVar*: NimNode
+
+    # All messages
+    messages*: seq[Message]
+
+    # Messages by type:
+    handshake*: Message
+    notifications*: seq[Message]
+    requests*: seq[Request]
+
+    # Output procs
+    outSendProcs*: NimNode
+    outRecvProcs*: NimNode
+    outProcRegistrations*: NimNode
+
+    # Event handlers
+    onPeerConnected*: NimNode
+    onPeerDisconnected*: NimNode
+
+  Backend* = ref object
+    # Code generators
+    implementMsg*: proc (p: P2PProtocol, msg: Message, resp: Message = nil)
+    implementProtocolInit*: proc (p: P2PProtocol): NimNode
+    afterProtocolInit*: proc (p: P2PProtocol)
+
+    # Bound symbols to the back-end run-time types and procs
+    PeerType*: NimNode
+    NetworkType*: NimNode
+
+    registerProtocol*: NimNode
+    setEventHandlers*: NimNode
+
+  BackendFactory* = proc (p: P2PProtocol): Backend
+
+const
+  defaultReqTimeout = 10.seconds
+
+proc createPeerState[Peer, ProtocolState](peer: Peer): RootRef =
+  var res = new ProtocolState
+  mixin initProtocolState
+  initProtocolState(res, peer)
+  return cast[RootRef](res)
+
+proc createNetworkState[NetworkNode, NetworkState](network: NetworkNode): RootRef {.gcsafe.} =
+  var res = new NetworkState
+  mixin initProtocolState
+  initProtocolState(res, network)
+  return cast[RootRef](res)
+
+proc expectBlockWithProcs*(n: NimNode): seq[NimNode] =
+  template helperName: auto = $n[0]
+
+  if n.len != 2 or n[1].kind != nnkStmtList:
+    error(helperName & " expects a block", n)
+
+  for p in n[1]:
+    if p.kind == nnkProcDef:
+      result.add p
+    elif p.kind == nnkCommentStmt:
+      continue
+    else:
+      error(helperName & " expects a proc definition.", p)
+
+proc nameOrNil*(procDef: NimNode): NimNode =
+  if procDef != nil:
+    procDef.name
+  else:
+    newNilLit()
+
+proc chooseFieldType(n: NimNode): NimNode =
+  ## Examines the parameter types used in the message signature
+  ## and selects the corresponding field type for use in the
+  ## message object type (i.e. `p2p.hello`).
+  ##
+  ## For now, only openarray types are remapped to sequences.
+  result = n
+  if n.kind == nnkBracketExpr and eqIdent(n[0], "openarray"):
+    result = n.copyNimTree
+    result[0] = ident("seq")
+
+proc verifyStateType(t: NimNode): NimNode =
+  result = t[1]
+  if result.kind == nnkSym and $result == "nil":
+    return nil
+  if result.kind != nnkBracketExpr or $result[0] != "ref":
+    error $result & " must be a ref type"
+
+proc processProtocolBody*(p: P2PProtocol, protocolBody: NimNode)
+
+proc init*(T: type P2PProtocol, backendFactory: BackendFactory,
+           name: string, version: int, body: NimNode,
+           timeouts: int64, useRequestIds: bool, shortName: string,
+           outgoingRequestDecorator: NimNode,
+           incomingRequestDecorator: NimNode,
+           incomingRequestThunkDecorator: NimNode,
+           incomingResponseDecorator: NimNode,
+           incomingResponseThunkDecorator: NimNode,
+           peerState, networkState: NimNode): P2PProtocol =
+
+  result = P2PProtocol(
+    name: name,
+    version: version,
+    timeouts: timeouts,
+    useRequestIds: useRequestIds,
+    shortName: shortName,
+    outgoingRequestDecorator: outgoingRequestDecorator,
+    incomingRequestDecorator: incomingRequestDecorator,
+    incomingRequestThunkDecorator: incomingRequestThunkDecorator,
+    incomingResponseDecorator: incomingResponseDecorator,
+    incomingResponseThunkDecorator: incomingResponseThunkDecorator,
+    PeerStateType: verifyStateType peerState,
+    NetworkStateType: verifyStateType networkState,
+    nameIdent: ident(name),
+    protocolInfoVar: ident(name & "Protocol"),
+    outSendProcs: newStmtList(),
+    outRecvProcs: newStmtList(),
+    outProcRegistrations: newStmtList())
+
+  result.backend = backendFactory(result)
+  result.processProtocolBody body
+
+  if not result.backend.afterProtocolInit.isNil:
+    result.backend.afterProtocolInit(result)
+
+proc augmentUserHandler(p: P2PProtocol, userHandlerProc: NimNode, msgId = -1) =
+  ## This procs adds a set of common helpers available in all messages handlers
+  ## (e.g. `perProtocolMsgId`, `peer.state`, etc).
+  var
+    prelude = newStmtList()
+    getState = ident"getState"
+    getNetworkState = ident"getNetworkState"
+    currentProtocolSym = ident"CurrentProtocol"
+    perProtocolMsgId = ident"perProtocolMsgId"
+    protocolInfoVar = p.protocolInfoVar
+    protocolNameIdent = p.nameIdent
+    PeerType = p.backend.PeerType
+    PeerStateType = p.PeerStateType
+    NetworkStateType = p.NetworkStateType
+
+  userHandlerProc.addPragma ident"gcsafe"
+  userHandlerProc.addPragma ident"async"
+
+  userHandlerProc.body.insert 0, prelude
+
+  when false:
+    # TODO
+    ## Turns a regular proc definition into an async proc and adds
+    ## the helpers for accessing the peer and network protocol states.
+    case msgKind
+    of msgRequest:  userHandlerProc.applyDecorator incomingRequestDecorator
+    of msgResponse: userHandlerProc.applyDecorator incomingResponseDecorator
+    else: discard
+
+  # 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])
+
+  prelude.add quote do:
+    type `currentProtocolSym` = `protocolNameIdent`
+
+  if msgId >= 0:
+    prelude.add quote do:
+      const `perProtocolMsgId` = `msgId`
+
+  # Define local accessors for the peer and the network protocol states
+  # inside each user message handler proc (e.g. peer.state.foo = bar)
+  if PeerStateType != nil:
+    prelude.add quote do:
+      template state(p: `PeerType`): `PeerStateType` =
+        cast[`PeerStateType`](`getState`(p, `protocolInfoVar`))
+
+  if NetworkStateType != nil:
+    prelude.add quote do:
+      template networkState(p: `PeerType`): `NetworkStateType` =
+        cast[`NetworkStateType`](`getNetworkState`(p.network, `protocolInfoVar`))
+
+proc addPreludeDefs*(userHandlerProc: NimNode, definitions: NimNode) =
+  userHandlerProc.body[0].add definitions
+
+proc eventHandlerToProc(p: P2PProtocol, 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 = ident(p.name & handlerName) # genSym(nskProc, p.name & handlerName)
+  p.augmentUserHandler result
+
+proc ensureTimeoutParam(procDef: NimNode, timeouts: int64): NimNode =
+  ## Make sure the messages has a timeout parameter and it has the correct type.
+  ## The parameter will be removed from the signature and returned for caching
+  ## in the Message's timeoutParam field. It is needed only for the send procs.
+  var
+    Duration = bindSym"Duration"
+    milliseconds = bindSym"milliseconds"
+    lastParam = procDef.params[^1]
+
+  if eqIdent(lastParam[0], "timeout"):
+    if lastParam[2].kind == nnkEmpty:
+      error "You must specify a default value for the `timeout` parameter", lastParam
+    lastParam[2] = newCall(milliseconds, newLit(100))#  newCall(Duration, lastParam[2])
+    if lastParam[1].kind == nnkEmpty:
+      lastParam[1] = Duration
+    elif not eqIdent(lastParam[1], "Duration"):
+      error "The timeout parameter should be of type 'chronos.Duration'", lastParam[1]
+
+    result = lastParam
+    procDef.params.del(procDef.params.len - 1)
+
+  else:
+    result = newTree(nnkIdentDefs,
+                     ident"timeout",
+                     Duration,
+                     newCall(milliseconds, newLit(timeouts)))
+
+proc newMsg(p: P2PProtocol, kind: MessageKind, id: int,
+            procDef: NimNode, timeoutParam: NimNode = nil): Message =
+
+  if procDef[0].kind == nnkPostfix:
+    error("p2pProcotol procs are public by default. " &
+          "Please remove the postfix `*`.", procDef)
+
+  var
+    msgIdent = procDef.name
+    msgName = $msgIdent
+    recFields = newTree(nnkRecList)
+    recBody = newTree(nnkObjectTy, newEmptyNode(), newEmptyNode(), recFields)
+    recName = ident(msgName & "Obj")
+
+  for param, paramType in procDef.typedParams(skip = 1):
+    recFields.add newTree(nnkIdentDefs,
+      newTree(nnkPostfix, ident("*"), param), # The fields are public
+      chooseFieldType(paramType),             # some types such as openarray
+                                              # are automatically remapped
+      newEmptyNode())
+
+  result = Message(id: id, ident: msgIdent, kind: kind,
+                   procDef: procDef, recIdent: recName, recBody: recBody,
+                   timeoutParam: timeoutParam)
+
+  if procDef.body.kind != nnkEmpty:
+    result.userHandler = copy procDef
+    p.augmentUserHandler result.userHandler
+    result.userHandler.name = genSym(nskProc, msgName)
+
+  p.messages.add result
+
+proc identWithExportMarker*(msg: Message): NimNode =
+  newTree(nnkPostfix, ident("*"), msg.ident)
+
+proc createSendProc*(msg: Message, procType = nnkProcDef): NimNode =
+  # TODO: file an issue:
+  # macros.newProc and macros.params doesn't work with nnkMacroDef
+
+  let pragmas = if procType == nnkProcDef: newTree(nnkPragma, ident"gcsafe")
+                else: newEmptyNode()
+
+  result = newNimNode(procType).add(
+    msg.identWithExportMarker, ## name
+    newEmptyNode(),
+    newEmptyNode(),
+    msg.procDef.params.copy, ## params
+    pragmas,
+    newEmptyNode(),
+    newStmtList()) ## body
+
+  if msg.kind in {msgHandshake, msgRequest}:
+    result[3].add msg.timeoutParam
+
+  result[3][0] = if procType == nnkMacroDef: ident "untyped"
+                 else: newTree(nnkBracketExpr, ident("Future"), msg.recIdent)
+
+proc appendAllParams*(node: NimNode, procDef: NimNode, skipFirst = 0): NimNode =
+  result = node
+  for p, _ in procDef.typedParams(skip = skipFirst):
+    result.add p
+
+proc netInit*(p: P2PProtocol): NimNode =
+  if p.NetworkStateType == nil:
+    newNilLit()
+  else:
+    newTree(nnkBracketExpr, bindSym"createNetworkState",
+                            p.backend.NetworkType,
+                            p.NetworkStateType)
+
+proc peerInit*(p: P2PProtocol): NimNode =
+  if p.PeerStateType == nil:
+    newNilLit()
+  else:
+    newTree(nnkBracketExpr, bindSym"createPeerState",
+                            p.backend.PeerType,
+                            p.PeerStateType)
+
+proc processProtocolBody*(p: P2PProtocol, protocolBody: NimNode) =
+  ## This procs handles all DSL statements valid inside a p2pProtocol.
+  ##
+  ## It will populate the protocol's fields such as:
+  ##   * handshake
+  ##   * requests
+  ##   * notifications
+  ##   * onPeerConnected
+  ##   * onPeerDisconnected
+  ##
+  ## All messages will have properly computed numeric IDs
+  ##
+  var nextId = 0
+
+  for n in protocolBody:
+    case n.kind
+    of {nnkCall, nnkCommand}:
+      if eqIdent(n[0], "nextID"):
+        # By default message IDs are assigned in increasing order
+        # `nextID` can be used to skip some of the numeric slots
+        if n.len == 2 and n[1].kind == nnkIntLit:
+          nextId = n[1].intVal.int
+        else:
+          error("nextID expects a single int value", n)
+
+      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.
+        let procs = expectBlockWithProcs(n)
+        if procs.len < 2:
+          error "requestResponse expects a block with at least two proc definitions"
+
+        var queries = newSeq[Message]()
+        for i in 0 .. procs.len - 2:
+          var timeout = ensureTimeoutParam(procs[i], p.timeouts)
+          queries.add p.newMsg(msgRequest, nextId + i, procs[i], timeout)
+
+        p.requests.add Request(
+          queries: queries,
+          response: p.newMsg(msgResponse, nextId + procs.len - 1, procs[^1]))
+
+        inc nextId, procs.len
+
+      elif eqIdent(n[0], "handshake"):
+        let procs = expectBlockWithProcs(n)
+        if procs.len != 1:
+          error "handshake expects a block with a single proc definition", n
+
+        if p.handshake != nil:
+          error "The handshake for the protocol is already defined", n
+
+        var timeout = ensureTimeoutParam(procs[0], p.timeouts)
+        p.handshake = p.newMsg(msgHandshake, nextId, procs[0], timeout)
+        inc nextId
+
+      elif eqIdent(n[0], "onPeerConnected"):
+        p.onPeerConnected = p.eventHandlerToProc(n[1], "PeerConnected")
+
+      elif eqIdent(n[0], "onPeerDisconnected"):
+        p.onPeerDisconnected = p.eventHandlerToProc(n[1], "PeerDisconnected")
+
+      else:
+        error(repr(n) & " is not a recognized call in P2P protocol definitions", n)
+
+    of nnkProcDef:
+      p.notifications.add p.newMsg(msgNotification, nextId, n)
+      inc nextId
+
+    of nnkCommentStmt:
+      discard
+
+    else:
+      error "Illegal syntax in a P2P protocol definition", n
+
+proc genTypeSection*(p: P2PProtocol): NimNode =
+  var
+    protocolName = p.nameIdent
+    peerState = p.PeerStateType
+    networkState= p.NetworkStateType
+
+  result = newStmtList()
+  result.add quote do:
+    # Create a type acting as a pseudo-object representing the protocol
+    # (e.g. p2p)
+    type `protocolName`* = object
+
+  if peerState != nil:
+    result.add quote do:
+      template State*(P: type `protocolName`): type = `peerState`
+
+  if networkState != nil:
+    result.add quote do:
+      template NetworkState*(P: type `protocolName`): type = `networkState`
+
+  for msg in p.messages:
+    let
+      msgId = msg.id
+      msgName = msg.ident
+      msgRecName = msg.recIdent
+      msgRecBody = msg.recBody
+
+    result.add quote do:
+      # This is a type featuring a single field for each message param:
+      type `msgRecName`* = `msgRecBody`
+
+      # Add a helper template for accessing the message type:
+      # e.g. p2p.hello:
+      template `msgName`*(T: type `protocolName`): type = `msgRecName`
+
+      # Add a helper template for obtaining the message Id for
+      # a particular message type:
+      template msgId*(T: type `msgRecName`): int = `msgId`
+      template msgProtocol*(T: type `msgRecName`): type = `protocolName`
+
+proc genCode*(p: P2PProtocol): NimNode =
+  # TODO: try switching to a simpler for msg in p.messages: loop
+  if p.handshake != nil:
+    p.backend.implementMsg p, p.handshake
+
+  for msg in p.notifications:
+    p.backend.implementMsg p, msg
+
+  for req in p.requests:
+    p.backend.implementMsg p, req.response
+    for query in req.queries: p.backend.implementMsg(p, query, req.response)
+
+  result = newStmtList()
+  result.add p.genTypeSection()
+
+  let
+    protocolInfoVar = p.protocolInfoVar
+    protocolName = p.nameIdent
+    protocolInit = p.backend.implementProtocolInit(p)
+
+  result.add quote do:
+    # One global variable per protocol holds the protocol run-time data
+    var p = `protocolInit`
+    var `protocolInfoVar` = addr p
+
+    # The protocol run-time data is available as a pseudo-field
+    # (e.g. `p2p.protocolInfo`)
+    template protocolInfo*(P: type `protocolName`): auto = `protocolInfoVar`
+
+  result.add p.outSendProcs,
+             p.outRecvProcs,
+             p.outProcRegistrations
+
+  if p.onPeerConnected != nil: result.add p.onPeerConnected
+  if p.onPeerDisconnected != nil: result.add p.onPeerDisconnected
+
+  result.add newCall(p.backend.setEventHandlers,
+                     protocolInfoVar,
+                     nameOrNil p.onPeerConnected,
+                     nameOrNil p.onPeerDisconnected)
+
+  result.add newCall(p.backend.registerProtocol, protocolInfoVar)
+
+macro emitForSingleBackend(
+    name: static[string],
+    version: static[int],
+    backend: static[BackendFactory],
+    body: untyped,
+    # TODO Nim can't handle a proper duration paramter here
+    timeouts: static[int64] = defaultReqTimeout.milliseconds,
+    useRequestIds: static[bool] = true,
+    shortName: static[string] = "",
+    outgoingRequestDecorator: untyped = nil,
+    incomingRequestDecorator: untyped = nil,
+    incomingRequestThunkDecorator: untyped = nil,
+    incomingResponseDecorator: untyped = nil,
+    incomingResponseThunkDecorator: untyped = nil,
+    peerState = type(nil),
+    networkState = type(nil)): untyped =
+
+  var p = P2PProtocol.init(
+    backend,
+    name, version, body, timeouts,
+    useRequestIds, shortName,
+    outgoingRequestDecorator,
+    incomingRequestDecorator,
+    incomingRequestThunkDecorator,
+    incomingResponseDecorator,
+    incomingResponseThunkDecorator,
+    peerState.getType, networkState.getType)
+
+  result = p.genCode()
+
+  when defined(debugRlpxProtocol) or defined(debugMacros):
+    echo repr(result)
+
+macro emitForAllBackends(backendSyms: typed, options: untyped, body: untyped): untyped =
+  let name = $(options[0])
+
+  var backends = newSeq[NimNode]()
+  if backendSyms.kind == nnkSym:
+    backends.add backendSyms
+  else:
+    for backend in backendSyms:
+      backends.add backend
+
+  result = newStmtList()
+
+  for backend in backends:
+    let call = copy options
+    call[0] = bindSym"emitForSingleBackend"
+    call.add newTree(nnkExprEqExpr, ident("name"), newLit(name))
+    call.add newTree(nnkExprEqExpr, ident("backend"), backend)
+    call.add newTree(nnkExprEqExpr, ident("body"), body)
+    result.add call
+
+template p2pProtocol*(options: untyped, body: untyped) {.dirty.} =
+  bind emitForAllBackends
+  emitForAllBackends(p2pProtocolBackendImpl, options, body)
+

eth/p2p/private/p2p_types.nim

@@ -144,11 +144,6 @@ type
   DisconnectionHandler* = proc(peer: Peer,
                                reason: DisconnectionReason): Future[void] {.gcsafe.}
 
-  RlpxMessageKind* = enum
-    rlpxNotification,
-    rlpxRequest,
-    rlpxResponse
-
   ConnectionState* = enum
     None,
     Connecting,
@@ -177,3 +172,5 @@ type
 
   Response*[MsgType] = distinct Peer
 
+proc `$`*(peer: Peer): string = $peer.remote
+

eth/p2p/rlpx.nim

@@ -1,18 +1,20 @@
 import
   macros, tables, algorithm, deques, hashes, options, typetraits,
   std_shims/macros_shim, chronicles, nimcrypto, chronos, eth/[rlp, common, keys, async_utils],
-  private/p2p_types, kademlia, auth, rlpxcrypt, enode
+  private/p2p_types, kademlia, auth, rlpxcrypt, enode, p2p_protocol_dsl
 
 when useSnappy:
   import snappy
   const devp2pSnappyVersion* = 5
 
+export
+  p2pProtocol
+
 logScope:
   topics = "rlpx"
 
 const
   devp2pVersion* = 4
-  defaultReqTimeout = milliseconds(10000)
   maxMsgSize = 1024 * 1024
 
 include p2p_tracing
@@ -305,10 +307,10 @@ proc send*[Msg](peer: Peer, msg: Msg): Future[void] =
   rlpWriter.appendRecordType(msg, Msg.rlpFieldsCount > 1)
   peer.sendMsg rlpWriter.finish
 
-proc registerRequest*(peer: Peer,
+proc registerRequest(peer: Peer,
-                      timeout: Duration,
+                     timeout: Duration,
-                      responseFuture: FutureBase,
+                     responseFuture: FutureBase,
-                      responseMsgId: int): int =
+                     responseMsgId: int): int =
   inc peer.lastReqId
   result = peer.lastReqId
 
@@ -581,164 +583,74 @@ proc dispatchMessages*(peer: Peer) {.async.} =
         return
       peer.awaitedMessages[msgId] = nil
 
-macro p2pProtocolImpl(name: static[string],
+template applyDecorator(p: NimNode, decorator: NimNode) =
-                      version: static[uint],
+  if decorator.kind != nnkNilLit: p.addPragma decorator
-                      body: untyped,
-                      # TODO Nim can't handle a proper duration paramter here
-                      timeout: static[int64] = defaultReqTimeout.milliseconds,
-                      useRequestIds: static[bool] = true,
-                      shortName: static[string] = "",
-                      outgoingRequestDecorator: untyped = nil,
-                      incomingRequestDecorator: untyped = nil,
-                      incomingRequestThunkDecorator: untyped = nil,
-                      incomingResponseDecorator: untyped = nil,
-                      incomingResponseThunkDecorator: untyped = nil,
-                      peerState = type(nil),
-                      networkState = type(nil)): untyped =
-  ## The macro used to defined RLPx 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:
-    outgoingRequestDecorator = outgoingRequestDecorator
-    incomingRequestDecorator = incomingRequestDecorator
-    incomingRequestThunkDecorator = incomingRequestThunkDecorator
-    incomingResponseDecorator = incomingResponseDecorator
-    incomingResponseThunkDecorator = incomingResponseThunkDecorator
-    useRequestIds = useRequestIds
-    version = version
-    defaultTimeout = timeout
 
-    nextId = 0
+proc p2pProtocolBackendImpl*(p: P2PProtocol): Backend =
-    protoName = name
+  let
-    shortName = if shortName.len > 0: shortName else: protoName
-    outTypes = newNimNode(nnkStmtList)
-    outSendProcs = newNimNode(nnkStmtList)
-    outRecvProcs = newNimNode(nnkStmtList)
-    outProcRegistrations = newNimNode(nnkStmtList)
-    protoNameIdent = ident(protoName)
     resultIdent = ident "result"
-    perProtocolMsgId = ident"perProtocolMsgId"
+    isSubprotocol = p.version > 0
-    response = ident"response"
-    currentProtocolSym = ident"CurrentProtocol"
-    protocol = ident(protoName & "Protocol")
-    isSubprotocol = version > 0'u
-    peerState = verifyStateType peerState.getType
-    networkState = verifyStateType networkState.getType
-    handshake = newNilLit()
-    disconnectHandler = newNilLit()
     Option = bindSym "Option"
     # XXX: Binding the int type causes instantiation failure for some reason
     # Int = bindSym "int"
     Int = ident "int"
     Peer = bindSym "Peer"
-    Duration = bindSym "Duration"
+    EthereumNode = bindSym "EthereumNode"
-    milliseconds = bindSym "milliseconds"
+    Response = bindSym "Response"
-    createNetworkState = bindSym "createNetworkState"
+    ResponseWithId = bindSym "ResponseWithId"
-    createPeerState = bindSym "createPeerState"
+    perProtocolMsgId = ident"perProtocolMsgId"
-    finish = bindSym "finish"
+
     initRlpWriter = bindSym "initRlpWriter"
     safeEnterList = bindSym "safeEnterList"
-    messagePrinter = bindSym "messagePrinter"
+    rlpFromBytes = bindSym "rlpFromBytes"
-    initProtocol = bindSym "initProtocol"
-    nextMsgResolver = bindSym "nextMsgResolver"
     append = bindSym("append", brForceOpen)
     read = bindSym("read", brForceOpen)
+    startList = bindSym "startList"
+    enterList = bindSym "enterList"
+    finish = bindSym "finish"
+
+    messagePrinter = bindSym "messagePrinter"
+    nextMsgResolver = bindSym "nextMsgResolver"
     registerRequest = bindSym "registerRequest"
     requestResolver = bindSym "requestResolver"
     resolveResponseFuture = bindSym "resolveResponseFuture"
-    rlpFromBytes = bindSym "rlpFromBytes"
     checkedRlpRead = bindSym "checkedRlpRead"
     sendMsg = bindSym "sendMsg"
-    startList = bindSym "startList"
+    nextMsg = bindSym "nextMsg"
+    initProtocol = bindSym"initProtocol"
+    registerMsg = bindSym "registerMsg"
     writeMsgId = bindSym "writeMsgId"
-    getState = bindSym "getState"
-    getNetworkState = bindSym "getNetworkState"
     perPeerMsgId = bindSym "perPeerMsgId"
     perPeerMsgIdImpl = bindSym "perPeerMsgIdImpl"
     linkSendFailureToReqFuture = bindSym "linkSendFailureToReqFuture"
+    shortName = if p.shortName.len > 0: p.shortName else: p.name
 
   # By convention, all Ethereum protocol names must be abbreviated to 3 letters
   doAssert shortName.len == 3
 
-  template applyDecorator(p: NimNode, decorator: NimNode) =
+  new result
-    if decorator.kind != nnkNilLit: p.addPragma decorator
 
-  proc augmentUserHandler(userHandlerProc: NimNode,
+  result.registerProtocol = bindSym "registerProtocol"
-                          msgId = -1,
+  result.setEventHandlers = bindSym "setEventHandlers"
-                          msgKind = rlpxNotification,
+  result.PeerType = Peer
-                          extraDefinitions: NimNode = nil) =
+  result.NetworkType = EthereumNode
-    ## Turns a regular proc definition into an async proc and adds
-    ## the helpers for accessing the peer and network protocol states.
-    case msgKind
-    of rlpxRequest:  userHandlerProc.applyDecorator incomingRequestDecorator
-    of rlpxResponse: userHandlerProc.applyDecorator incomingResponseDecorator
-    else: discard
-
-    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
-
-    if msgId >= 0:
-      userHandlerDefinitions.add quote do:
-        const `perProtocolMsgId` = `msgId`
-
-    # 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 ...)
-    var fn = newTree(nnkProcDef)
-    doBlock.copyChildrenTo(fn)
-    result = genSym(nskProc, protoName & handlerName)
-    fn.name = result
-    augmentUserHandler fn
-    outRecvProcs.add fn
-
-  proc addMsgHandler(msgId: int, n: NimNode,
-                     msgKind = rlpxNotification,
-                     responseMsgId = -1,
-                     responseRecord: NimNode = nil): NimNode =
-    if n[0].kind == nnkPostfix:
-      macros.error("p2pProcotol procs are public by default. " &
-                   "Please remove the postfix `*`.", n)
-
-    let
-      msgIdent = n.name
-      msgName = $n.name
-      hasReqIds = useRequestIds and msgKind in {rlpxRequest, rlpxResponse}
 
+  result.implementMsg = proc (p: P2PProtocol, msg: Message, resp: Message = nil) =
     var
+      msgId = msg.id
+      msgRecName = msg.recIdent
+      msgKind = msg.kind
+      n = msg.procDef
+      responseMsgId = if resp != nil: resp.id else: -1
+      responseRecord = if resp != nil: resp.recIdent else: nil
+      msgIdent = n.name
+      msgName = $msgIdent
+      hasReqIds = p.useRequestIds and msgKind in {msgRequest, msgResponse}
       userPragmas = n.pragma
 
       # variables used in the sending procs
       msgRecipient = ident"msgRecipient"
       sendTo = ident"sendTo"
-      reqTimeout: NimNode
       rlpWriter = ident"writer"
       appendParams = newNimNode(nnkStmtList)
       paramsToWrite = newSeq[NimNode](0)
@@ -754,37 +666,16 @@ macro p2pProtocolImpl(name: static[string],
       callResolvedResponseFuture = 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 hasReqIds:
       # Messages using request Ids
       readParams.add quote do:
         let `reqId` = `read`(`receivedRlp`, int)
 
     case msgKind
-    of rlpxNotification: discard
+    of msgRequest:
-    of rlpxRequest:
-      # 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",
-                             Duration, newCall(milliseconds, newLit(defaultTimeout)))
-
       let reqToResponseOffset = responseMsgId - msgId
       let responseMsgId = quote do: `perPeerMsgIdVar` + `reqToResponseOffset`
 
@@ -794,7 +685,7 @@ macro p2pProtocolImpl(name: static[string],
       # assumes there is one outstanding request at a time (if there are
       # multiple requests we'll resolve them in FIFO order).
       let registerRequestCall = newCall(registerRequest, msgRecipient,
-                                                         reqTimeout[0],
+                                                         msg.timeoutParam[0],
                                                          resultIdent,
                                                          responseMsgId)
       if hasReqIds:
@@ -807,61 +698,51 @@ macro p2pProtocolImpl(name: static[string],
           initFuture `resultIdent`
           discard `registerRequestCall`
 
-    of rlpxResponse:
+    of msgResponse:
       let reqIdVal = if hasReqIds: `reqId` else: newLit(-1)
       callResolvedResponseFuture.add quote do:
         `resolveResponseFuture`(`msgSender`,
-                                `perPeerMsgId`(`msgSender`, `msgRecord`),
+                                `perPeerMsgId`(`msgSender`, `msgRecName`),
                                  addr(`receivedMsg`),
                                  `reqIdVal`)
       if hasReqIds:
         paramsToWrite.add newDotExpr(sendTo, ident"id")
 
-    if n.body.kind != nnkEmpty:
+    of msgHandshake, msgNotification: discard
-      # implement the receiving thunk proc that deserialzed the
-      # message parameters and calls the user proc:
-      userHandlerProc = n.copyNimTree
-      userHandlerProc.name = genSym(nskProc, msgName)
 
+    if msg.userHandler != nil:
       var extraDefs: NimNode
-      if msgKind == rlpxRequest:
+      if msgKind == msgRequest:
-        let peer = userHandlerProc.params[1][0]
+        let peer = msg.userHandler.params[1][0]
+        let response = ident"response"
         if hasReqIds:
           extraDefs = quote do:
-            let `response` = ResponseWithId[`responseRecord`](peer: `peer`, id: `reqId`)
+            let `response` = `ResponseWithId`[`responseRecord`](peer: `peer`, id: `reqId`)
         else:
           extraDefs = quote do:
-            let `response` = Response[`responseRecord`](`peer`)
+            let `response` = `Response`[`responseRecord`](`peer`)
 
-      augmentUserHandler userHandlerProc, msgId, msgKind, extraDefs
+        msg.userHandler.addPreludeDefs extraDefs
 
       # This is the call to the user supplied handled. Here we add only the
       # initial peer param, while the rest of the params will be added later.
-      userHandlerCall = newCall(userHandlerProc.name, msgSender)
+      userHandlerCall = newCall(msg.userHandler.name, msgSender)
 
       if hasReqIds:
-        userHandlerProc.params.insert(2, newIdentDefs(reqId, ident"int"))
+        msg.userHandler.params.insert(2, newIdentDefs(reqId, ident"int"))
         userHandlerCall.add reqId
 
       # 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)
 
-      outRecvProcs.add(userHandlerProc)
+      p.outRecvProcs.add(msg.userHandler)
 
     for param, paramType in n.typedParams(skip = 1):
       # This is a fragment of the sending proc that
       # serializes each of the passed parameters:
       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())
-
       # The received RLP data is deserialized to a local variable of
       # the message-specific type. This is done field by field here:
       let msgNameLit = newLit(msgName)
@@ -885,7 +766,7 @@ macro p2pProtocolImpl(name: static[string],
     var thunkProc = quote do:
       proc `thunkName`(`msgSender`: `Peer`, _: int, data: Rlp) {.gcsafe.} =
         var `receivedRlp` = data
-        var `receivedMsg` {.noinit.}: `msgRecord`
+        var `receivedMsg` {.noinit.}: `msgRecName`
         `readParamsPrelude`
         `readParams`
         `awaitUserHandler`
@@ -894,59 +775,48 @@ macro p2pProtocolImpl(name: static[string],
     for p in userPragmas: thunkProc.addPragma p
 
     case msgKind
-    of rlpxRequest:  thunkProc.applyDecorator incomingRequestThunkDecorator
+    of msgRequest:  thunkProc.applyDecorator p.incomingRequestThunkDecorator
-    of rlpxResponse: thunkProc.applyDecorator incomingResponseThunkDecorator
+    of msgResponse: thunkProc.applyDecorator p.incomingResponseThunkDecorator
     else: discard
 
     thunkProc.addPragma ident"async"
 
-    outRecvProcs.add thunkProc
+    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`
-
-      # Add a helper template for obtaining the message Id for
-      # a particular message type:
-      template msgId*(T: type `msgRecord`): int = `msgId`
-      template msgProtocol*(T: type `msgRecord`): type = `protoNameIdent`
 
     var msgSendProc = n
     let msgSendProcName = n.name
-    outSendProcs.add msgSendProc
+    p.outSendProcs.add msgSendProc
 
     # TODO: check that the first param has the correct type
     msgSendProc.params[1][0] = sendTo
     msgSendProc.addPragma ident"gcsafe"
 
-    # Add a timeout parameter for all request procs
     case msgKind
-    of rlpxRequest:
+    of msgRequest:
-      msgSendProc.params.add reqTimeout
+      # Add a timeout parameter for all request procs
-    of rlpxResponse:
+      msgSendProc.params.add msg.timeoutParam
+    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 rsp = bindSym "Response"
+      # let rspId = bindSym "ResponseWithId"
       let
-        ResponseTypeHead = if useRequestIds: bindSym"ResponseWithId"
+        ResponseTypeHead = if p.useRequestIds: ResponseWithId
-                           else: bindSym"Response"
+                           else: Response
-        ResponseType = newTree(nnkBracketExpr, ResponseTypeHead, msgRecord)
+        ResponseType = newTree(nnkBracketExpr, ResponseTypeHead, msgRecName)
 
       msgSendProc.params[1][1] = ResponseType
 
-      outSendProcs.add quote do:
+      p.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 = if msgKind != rlpxRequest: ident"void"
+    let rt = if msgKind != msgRequest: ident"void"
              else: newTree(nnkBracketExpr, Option, responseRecord)
     msgSendProc.params[0] = newTree(nnkBracketExpr, ident("Future"), rt)
 
@@ -956,7 +826,7 @@ macro p2pProtocolImpl(name: static[string],
       let `msgBytes` = `finish`(`rlpWriter`)
 
     var sendCall = newCall(sendMsg, msgRecipient, msgBytes)
-    let senderEpilogue = if msgKind == rlpxRequest:
+    let senderEpilogue = if msgKind == msgRequest:
       # In RLPx requests, the returned future was allocated here and passed
       # to `registerRequest`. It's already assigned to the result variable
       # of the proc, so we just wait for the sending operation to complete
@@ -969,7 +839,7 @@ macro p2pProtocolImpl(name: static[string],
       quote: return `sendCall`
 
     let perPeerMsgIdValue = if isSubprotocol:
-      newCall(perPeerMsgIdImpl, msgRecipient, protocol, newLit(msgId))
+      newCall(perPeerMsgIdImpl, msgRecipient, p.protocolInfoVar, newLit(msgId))
     else:
       newLit(msgId)
 
@@ -983,8 +853,39 @@ macro p2pProtocolImpl(name: static[string],
     for p in paramsToWrite:
       appendParams.add newCall(append, rlpWriter, p)
 
-    # Make the send proc public
+    if msgKind == msgHandshake:
-    msgSendProc.name = newTree(nnkPostfix, ident("*"), msgSendProc.name)
+      var
+        rawSendProc = genSym(nskProc, msgName & "RawSend")
+        handshakeExchanger = newProc(name = msg.identWithExportMarker,
+                                     procType = nnkTemplateDef)
+
+      handshakeExchanger.params = msgSendProc.params.copyNimTree
+      handshakeExchanger.params.add msg.timeoutParam
+      handshakeExchanger.params[0] = newTree(nnkBracketExpr, ident("Future"), msgRecName)
+
+      var
+        forwardCall = newCall(rawSendProc).appendAllParams(handshakeExchanger)
+        peerVariable = ident"peer"
+        peerValue = forwardCall[1]
+        timeoutValue = msg.timeoutParam[0]
+        handshakeImpl = ident"handshakeImpl"
+
+      forwardCall[1] = peerVariable
+      forwardCall.del(forwardCall.len - 1)
+
+      handshakeExchanger.body = quote do:
+        let `peerVariable` = `peerValue`
+        let sendingFuture = `forwardCall`
+        `handshakeImpl`(`peerVariable`,
+                        sendingFuture,
+                        `nextMsg`(`peerVariable`, `msgRecName`),
+                        `timeoutValue`)
+
+      msgSendProc.name = rawSendProc
+      p.outSendProcs.add handshakeExchanger
+    else:
+      # Make the send proc public
+      msgSendProc.name = msg.identWithExportMarker
 
     let initWriter = quote do:
       var `rlpWriter` = `initRlpWriter`()
@@ -1003,123 +904,24 @@ macro p2pProtocolImpl(name: static[string],
       `finalizeRequest`
       `senderEpilogue`
 
-    if msgKind == rlpxRequest:
+    if msgKind == msgRequest:
-      msgSendProc.applyDecorator outgoingRequestDecorator
+      msgSendProc.applyDecorator p.outgoingRequestDecorator
 
-    outProcRegistrations.add(
+    p.outProcRegistrations.add(
-      newCall(bindSym("registerMsg"),
+      newCall(registerMsg,
-              protocol,
+              p.protocolInfoVar,
               newIntLitNode(msgId),
               newStrLitNode($n.name),
               thunkName,
-              newTree(nnkBracketExpr, messagePrinter, msgRecord),
+              newTree(nnkBracketExpr, messagePrinter, msgRecName),
-              newTree(nnkBracketExpr, requestResolver, msgRecord),
+              newTree(nnkBracketExpr, requestResolver, msgRecName),
-              newTree(nnkBracketExpr, nextMsgResolver, msgRecord)))
+              newTree(nnkBracketExpr, nextMsgResolver, msgRecName)))
 
-  outTypes.add quote do:
+  result.implementProtocolInit = proc (p: P2PProtocol): NimNode =
-    # Create a type acting as a pseudo-object representing the protocol
+    return newCall(initProtocol,
-    # (e.g. p2p)
+                   newLit(p.shortName),
-    type `protoNameIdent`* = object
+                   newLit(p.version),
-
+                   p.peerInit, p.netInit)
-  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"):
-        # By default message IDs are assigned in increasing order
-        # `nextID` can be used to skip some of the numeric slots
-        if n.len == 2 and n[1].kind == nnkIntLit:
-          nextId = n[1].intVal.int
-        else:
-          macros.error("nextID expects a single int value", n)
-      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 responseMsgId = nextId + procs.len - 1
-              let responseRecord = addMsgHandler(responseMsgId,
-                                                 procs[^1],
-                                                 msgKind = rlpxResponse)
-              for i in 0 .. procs.len - 2:
-                discard addMsgHandler(nextId + i, procs[i],
-                                      msgKind = rlpxRequest,
-                                      responseMsgId = responseMsgId,
-                                      responseRecord = responseRecord)
-
-              inc nextId, procs.len
-
-              # 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"):
-        handshake = liftEventHandler(n[1], "Handshake")
-      elif eqIdent(n[0], "onPeerDisconnected"):
-        disconnectHandler = liftEventHandler(n[1], "PeerDisconnect")
-      else:
-        macros.error(repr(n) & " is not a recognized call in P2P protocol definitions", n)
-    of nnkProcDef:
-      discard addMsgHandler(nextId, n)
-      inc nextId
-
-    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`(`shortName`, `version`, `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(debugRlpxProtocol) 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))
 
 p2pProtocol devp2p(version = 0, shortName = "p2p"):
   proc hello(peer: Peer,
@@ -1162,7 +964,7 @@ proc callDisconnectHandlers(peer: Peer, reason: DisconnectionReason): Future[voi
 
   return all(futures)
 
-proc handshakeImpl[T](peer: Peer,
+proc handshakeImpl*[T](peer: Peer,
                       sendFut: Future[void],
                       responseFut: Future[T],
                       timeout: Duration): Future[T] {.async.} =
@@ -1180,21 +982,6 @@ proc handshakeImpl[T](peer: Peer,
   else:
     return responseFut.read
 
-proc handshakeImpl(peer: Peer,
-                   sendFut: Future[void],
-                   timeout: Duration,
-                   HandshakeType: type): Future[HandshakeType] =
-  handshakeImpl(peer, sendFut, nextMsg(peer, HandshakeType), timeout)
-
-macro handshake*(peer: Peer, timeout: untyped, sendCall: untyped): untyped =
-  let
-    msgName = $sendCall[0]
-    msgType = newDotExpr(ident"CurrentProtocol", ident(msgName))
-
-  sendCall.insert(1, peer)
-
-  result = newCall(bindSym"handshakeImpl", peer, sendCall, timeout, msgType)
-
 proc disconnect*(peer: Peer, reason: DisconnectionReason, notifyOtherPeer = false) {.async.} =
   if peer.connectionState notin {Disconnecting, Disconnected}:
     peer.connectionState = Disconnecting

eth/p2p/rlpx_protocols/eth_protocol.nim

@@ -46,12 +46,12 @@ p2pProtocol eth(version = protocolVersion,
       chain = network.chain
       bestBlock = chain.getBestBlockHeader
 
-    let m = await peer.handshake(timeout = chronos.seconds(10),
+    let m = await peer.status(protocolVersion,
-                                 status(protocolVersion,
+                              network.networkId,
-                                        network.networkId,
+                              bestBlock.difficulty,
-                                        bestBlock.difficulty,
+                              bestBlock.blockHash,
-                                        bestBlock.blockHash,
+                              chain.genesisHash,
-                                        chain.genesisHash))
+                              timeout = chronos.seconds(10))
 
     if m.networkId == network.networkId and m.genesisHash == chain.genesisHash:
       trace "suitable peer", peer
@@ -61,12 +61,13 @@ p2pProtocol eth(version = protocolVersion,
     peer.state.bestDifficulty = m.totalDifficulty
     peer.state.bestBlockHash = m.bestHash
 
-  proc status(peer: Peer,
+  handshake:
-              protocolVersion: uint,
+    proc status(peer: Peer,
-              networkId: uint,
+                protocolVersion: uint,
-              totalDifficulty: DifficultyInt,
+                networkId: uint,
-              bestHash: KeccakHash,
+                totalDifficulty: DifficultyInt,
-              genesisHash: KeccakHash)
+                bestHash: KeccakHash,
+                genesisHash: KeccakHash)
 
   proc newBlockHashes(peer: Peer, hashes: openarray[NewBlockHashesAnnounce]) =
     discard

eth/p2p/rlpx_protocols/les_protocol.nim

@@ -165,11 +165,8 @@ p2pProtocol les(version = lesVersion,
                 outgoingRequestDecorator = outgoingRequestDecorator,
                 incomingRequestDecorator = incomingRequestDecorator,
                 incomingResponseThunkDecorator = incomingResponseDecorator):
-
+  handshake:
-  ## Handshake
+    proc status(p: Peer, values: openarray[KeyValuePair])
-  ##
-
-  proc status(p: Peer, values: openarray[KeyValuePair])
 
   onPeerConnected do (peer: Peer):
     let
@@ -208,7 +205,7 @@ p2pProtocol les(version = lesVersion,
       lesProperties.add(keyAnnounceType => lesNetwork.ourAnnounceType)
 
     let
-      s = await peer.handshake(timeout = chronos.seconds(10), status(lesProperties))
+      s = await peer.status(lesProperties, timeout = chronos.seconds(10))
       peerNetworkId   = s.values.getRequiredValue(keyNetworkId, uint)
       peerGenesisHash = s.values.getRequiredValue(keyGenesisHash, KeccakHash)
       peerLesVersion = s.values.getRequiredValue(keyProtocolVersion, uint)

eth/p2p/rlpx_protocols/whisper_protocol.nim

@@ -733,11 +733,11 @@ p2pProtocol Whisper(version = whisperVersion,
       whisperNet = peer.networkState
       whisperPeer = peer.state
 
-    let m = await handshake(peer, timeout = chronos.milliseconds(500),
+    let m = await peer.status(whisperVersion,
-                            status(whisperVersion,
+                              cast[uint](whisperNet.config.powRequirement),
-                                   cast[uint](whisperNet.config.powRequirement),
+                              @(whisperNet.config.bloom),
-                                   @(whisperNet.config.bloom),
+                              whisperNet.config.isLightNode,
-                                   whisperNet.config.isLightNode))
+                              timeout = chronos.milliseconds(500))
 
     if m.protocolVersion == whisperVersion:
       debug "Whisper peer", peer, whisperVersion
@@ -769,12 +769,12 @@ p2pProtocol Whisper(version = whisperVersion,
 
     debug "Whisper peer initialized", peer
 
-  proc status(peer: Peer,
+  handshake:
-              protocolVersion: uint,
+    proc status(peer: Peer,
-              powConverted: uint,
+                protocolVersion: uint,
-              bloom: Bytes,
+                powConverted: uint,
-              isLightNode: bool) =
+                bloom: Bytes,
-    discard
+                isLightNode: bool)
 
   proc messages(peer: Peer, envelopes: openarray[Envelope]) =
     if not peer.state.initialized:
@@ -1051,7 +1051,6 @@ proc setLightNode*(node: EthereumNode, isLightNode: bool) =
   ## setting is only communicated at peer handshake
   node.protocolState(Whisper).config.isLightNode = isLightNode
 
-
 proc configureWhisper*(node: EthereumNode, config: WhisperConfig) =
   ## Apply a Whisper configuration
   ## NOTE: Should be run before connection is made with peers as some

tests/p2p/tserver.nim

@@ -71,7 +71,7 @@ p2pProtocol xyz(version = 1,
   proc bar(p: Peer, i: int, s: string)
 
   requestResponse:
-    proc xyzReq(p: Peer, n: int, timeout = 3000) =
+    proc xyzReq(p: Peer, n: int, timeout = 3.seconds) =
       echo "got req ", n
 
     proc xyzRes(p: Peer, data: string) =