node-simple-router/src/wamp.coffee

Yet another minimalistic router for node.js

# First shot at WAMP (Web Application Messaging Protocol) implementation.

events = require 'events'
util = require 'util'
net = require 'net'
ws = require './ws'
{defer} = require './promises'

try
  {defer} = require './promises.litcoffee'
catch e
  {defer} = require './promises'

#Message Constants

MESSAGE_TYPES =
  HELLO: 1
  WELCOME: 2
  ABORT: 3
  CHALLENGE: 4
  AUTHENTICATE: 5
  GOODBYE: 6
  HEARTBEAT: 7
  ERROR: 8
  PUBLISH: 16
  PUBLISHED: 17
  SUBSCRIBE: 32
  SUBSCRIBED: 33
  UNSUBSCRIBE: 34
  UNSUBSCRIBED: 35
  EVENT: 36
  CALL: 48
  CANCEL: 49
  RESULT: 50
  REGISTER: 64
  REGISTERED: 65
  UNREGISTER: 66
  UNREGISTERED: 67
  INVOCATION: 68
  INTERRUPT: 69
  YIELD: 70

#End of Message Constants

#Transport constants

TRANSPORT_TYPES =
  DIRECT: 1
  WEBSOCKET: 2
  UNIXSOCKET: 3

#End of Transport constants

MAX_ID = 2 ** 53

isValidURI = (uri_string) -> !!uri_string.match(/^(([0-9a-z_]{2,}\.)|\.)*([0-9a-z_]{2,})?$/)

randomNum = (len) ->
  parseInt ((Math.floor(Math.random() * 10)).toString() for n in [1..len]).join('')

genId = ->
  randomNum 15

###
class WampSession extends events.EventEmitter
  constructor: (@id, options) ->
    @_options = options or {}
    for key, val of @_options
      @[key] = val
    @nextId = 1
###

class WampPeer extends events.EventEmitter
  "Peer at one end of Wamp Session. Involves acting as a session itself, as well"

  constructor: (@parent, @transport, @roles, options) ->
    @isOpen = true
    @transport.on 'close', (code) =>
      @isOpen = false
      @cleanUp()
      console.log "Closing WampPeer due to transport closed."
    @id = null
    @nextId = 1
    @setOptions options

  setOptions: (options) =>
    @_options = options or {}
    for key, val of @_options
      @[key] = val

  cleanUp: =>
    registered = @parent.realms?[@realm].registered_procedures
    if registered
      for proc, index in registered
        try
          if proc.sessionId is @id
            @parent.realms[@realm].registered_procedures.splice(index, 1)
        catch e
          console.log "ERROR: #{e.message}"

    invocations = @parent.realms?[@realm].invocations
    if invocations
      for invocation, index in invocations
        try
          if invocation.sessionId is @id
            @parent.realms[@realm].invocations.splice(index, 1)
        catch e
          console.log "ERROR: #{e.message}"

    subscriptions = @parent.realms?[@realm].subscriptions
    if subscriptions
      for key, topic of subscriptions
        try
          for subscription, index in topic
            if subscription.sessionId is @id
              topic.splice(index, 1)
        catch e
          console.log "ERROR: #{e.message}"

    sessions = @parent.realms?[@realm].sessions
    if sessions
      for session, index in sessions
        try
          if session.id is @id
            @parent.realms[@realm].sessions.splice(index, 1)
            break
        catch e
          console.log "ERROR: #{e.message}"

  sendMessage: (message) =>
    ###
    if @parent.constructor.name is "WampClient"
      console.log @parent.constructor.name, "sends a message:", JSON.stringify(message)
      console.log "Open condition is:", @isOpen
      console.log "WebSocket state is: %s", @transport.readyState
    ###
    @transport.send(message) if @isOpen

  processMessage: (message) =>
    return unless @isOpen
    arr = JSON.parse message
    [code] = arr
    if code not in [MESSAGE_TYPES.HELLO, MESSAGE_TYPES.WELCOME]
      return unless @id
    switch code
      when MESSAGE_TYPES.HELLO
        console.log "Router received HELLO message"
        [realm, details] = arr.slice(1)
        #@session = new WampSession @parent.nextSessionId, {peer: @, realm, details}
        @id = @parent.nextSessionId
        @realm = realm
        @setOptions details
        @parent.realms[realm] = {sessions: [], registered_procedures: [], invocations: [], subscriptions: {}} unless realm of @parent.realms
        @parent.realms[realm].sessions.push @
        console.log "@realms[#{realm}].sessions.length: %d", @parent.realms[realm].sessions.length
        @sendMessage JSON.stringify [MESSAGE_TYPES.WELCOME, @parent.nextSessionId, {roles: @roles}]
        console.log "Router sent WELCOME message to #{@parent.nextSessionId}"
        @parent.nextSessionId += 1
      when MESSAGE_TYPES.WELCOME
        console.log "Client Received Welcome Message"
        [sid, details] = arr.slice(1)
        @id = sid
        @routerRoles = details
        @realm = @parent.realm
        @parent.subscriptions = @subscriptions = []
        @parent.publications = @publications = []
        @parent.registrations = @registrations = []
        @parent.calls = @calls = []
        @parent.onopen?({@id, @realm, @roles, @routerRoles, @subscriptions, @registrations, @calls})
      when MESSAGE_TYPES.ABORT
        console.log "Received Abort Message"
      when MESSAGE_TYPES.CHALLENGE
        console.log "Received Challenge Message"
      when MESSAGE_TYPES.AUTHENTICATE
        console.log "Received Authenticate Message"
      when MESSAGE_TYPES.GOODBYE
        console.log "Received GoodBye Message"
        @sendMessage message
        #@isOpen = false
        @cleanUp()
        @transport.close()
      when MESSAGE_TYPES.HEARTBEAT
        console.log "Received HeartBeat Message"
      when MESSAGE_TYPES.PUBLISH
        #console.log "Received publish message from session #{@id}"
        [RequestId, OptionsDict, TopicUri, ArgumentsList, ArgumentsKwDict] = arr.slice(1)
        PublicationId = @nextId
        @nextId += 1
        topic = @parent.realms[@realm].subscriptions[TopicUri]
        if topic
          for suscription in topic
            for session in @parent.realms[@realm].sessions
              if session.id is suscription.sessionId
                msgArray = [MESSAGE_TYPES.EVENT, suscription.SubscriptionId, PublicationId, OptionsDict]
                msgArray.push ArgumentsList if ArgumentsList
                msgArray.push ArgumentsKwDict if ArgumentsKwDict
                session.sendMessage JSON.stringify(msgArray)
                break
        if OptionsDict.acknowledge
          @sendMessage(JSON.stringify [MESSAGE_TYPES.PUBLISHED, RequestId, PublicationId])
      when MESSAGE_TYPES.PUBLISHED
        [RequestId, PublicationId] = arr.slice(1)
        console.log "Received Published Message for Request Id: #{RequestId} with Publication Id: #{PublicationId}"
        for publication in @parent.publications
          if publication.RequestId is RequestId
            publication.PublicatioId = PublicatioId
            console.log "Updated publication #{RequestId} with publication id: #{PublicationId}"
            break
      when MESSAGE_TYPES.SUBSCRIBE
        console.log "Received subscribe message from session #{@id}"
        [RequestId, OptionsDict, TopicUri] = arr.slice(1)
        SubscriptionId = @nextId
        @nextId += 1
        @parent.realms[@realm].subscriptions[TopicUri] = [] if not @parent.realms[@realm].subscriptions[TopicUri]
        @parent.realms[@realm].subscriptions[TopicUri].push {
        sessionId: @id
        SubscriptionId
        OptionsDict
        }
        resp = [MESSAGE_TYPES.SUBSCRIBED, RequestId, SubscriptionId]
        @sendMessage(JSON.stringify resp)
        console.log "Registered subscription for #{TopicUri} in realm #{@realm}"
      when MESSAGE_TYPES.SUBSCRIBED
        [RequestId, SubscriptionId] = arr.slice(1)
        console.log "Received Subscribed Message for Request Id: #{RequestId} with Subscription Id: #{SubscriptionId}"
        for subscription in @parent.subscriptions
          if subscription.RequestId is RequestId
            subscription.SubscriptionId = SubscriptionId
            console.log "Updated subscription #{subscription.topic} with subscription id: #{SubscriptionId}"
            break
      when MESSAGE_TYPES.UNSUBSCRIBE
        [RequestId, SubscriptionId] = arr.slice(1)
        console.log "Received unsubscribe message from session #{@id} with requestId: #{RequestId} and subscriptionId: #{SubscriptionId}"
        for key, topic of @parent.realms[@realm].subscriptions
          for subscription, index in topic
            if (subscription.SubscriptionId is SubscriptionId) and (subscription.sessionId is @id)
              console.log "Found subscription to erase at index #{index}. Going to do it for request: #{RequestId}"
              topic.splice(index, 1)
              return @sendMessage JSON.stringify([MESSAGE_TYPES.UNSUBSCRIBED, RequestId])
        console.log "Did not find a subscription to erase. Sending error message: 'wamp.error.no_such_subscription'"
        return @sendMessage JSON.stringify([MESSAGE_TYPES.ERROR, MESSAGE_TYPES.UNSUBSCRIBE, RequestId, {}, "wamp.error.no_such_subscription"])
      when MESSAGE_TYPES.UNSUBSCRIBED
        console.log "Received Unsubscribed Message"
      when MESSAGE_TYPES.EVENT
        [SubscriptionId, PublicationId, Details, args, kwArgs] = arr.slice(1)
        console.log "Received Event Message for subscription id: #{SubscriptionId} with the following args: %j", args
        for subscription in @subscriptions
          if subscription.SubscriptionId is SubscriptionId
            subscription.handler args, kwArgs
            break
      when MESSAGE_TYPES.CALL
        #console.log "Received Call Message from session #{@id} with request Id = #{arr[1]}"
        [RequestId, OptionsDict, ProcedureUri, ArgumentsList, ArgumentsKwDict] = arr.slice(1)
        for proc in @parent.realms[@realm].registered_procedures
          if proc.ProcedureUri is ProcedureUri
            callee_sessionId = proc.sessionId
            registrationId = proc.RegistrationId
            for session in @parent.realms[@realm].sessions
              if session.id is callee_sessionId
                callee_session = session
                invocation_message = [
                  MESSAGE_TYPES.INVOCATION,
                  RequestId,
                  registrationId,
                  OptionsDict,
                  ArgumentsList or [],
                  ArgumentsKwDict or {}
                ]
                @parent.realms[@realm].invocations.push {
                  sessionId: @id
                  requestId: RequestId
                }
                #console.log "Going to invoke requestId: #{RequestId} for registrationId: #{registrationId} on session: #{callee_session.id}"
                return callee_session.sendMessage(JSON.stringify invocation_message)
      when MESSAGE_TYPES.CANCEL
        console.log "Received Cancel Message"
      when MESSAGE_TYPES.RESULT
        [RequestId, OptionsDict, ArgumentsList, KwArguments] = arr.slice(1)
        console.log "Client received Result Message for request id: #{RequestId}. Results are: %j , %j", ArgumentsList, KwArguments
        for pendingCall, index in @calls
          if pendingCall.RequestId is RequestId
            ArgumentsList push KwArguments if Object.keys(KwArguments).length isnt 0
            #console.log "Client resolving '#{pendingCall.uri}' with %j", ArgumentsList
            #console.log "Pending call data:"
            #console.log k, v for k, v of pendingCall
            pendingCall.deferred?.resolve ArgumentsList
            @calls.splice index, 1
            break
      when MESSAGE_TYPES.REGISTER
        console.log "Router received register message from session #{@id}"
        [RequestId, OptionsDict, ProcedureUri] = arr.slice(1)
        for procedure in @parent.realms[@realm].registered_procedures
          if procedure.ProcedureUri is ProcedureUri
            console.log "ERROR: procedure #{ProcedureUri} already registered."
            return @sendMessage(JSON.stringify [MESSAGE_TYPES.ERROR, MESSAGE_TYPES.REGISTER, RequestId, {}, 'wamp.error.procedure_already_exists'])
        RegistrationId = @nextId
        @nextId += 1
        @parent.realms[@realm].registered_procedures.push {
          sessionId: @id
          RegistrationId
          OptionsDict
          ProcedureUri
        }
        resp = [MESSAGE_TYPES.REGISTERED, RequestId, RegistrationId]
        @sendMessage(JSON.stringify resp)
        console.log "Router registered procedure #{ProcedureUri} in realm #{@realm}"
      when MESSAGE_TYPES.REGISTERED
        [RequestId, RegistrationId] = arr.slice(1)
        console.log "Client received Registered Message for RequestId: %s - RegistrationId: %s", RequestId, RegistrationId
        for registered_procedure in @parent.registrations
          if registered_procedure.RequestId is RequestId
            registered_procedure.RegistrationId = RegistrationId
            console.log "Updated registered procedure #{registered_procedure.uri} with registration id: #{RegistrationId}"
            break
      when MESSAGE_TYPES.UNREGISTER
        console.log "Received Unregister Message"
        [RequestId, RegistrationId] = arr.slice(1)
        for procedure, index in @parent.realms[@realm].registered_procedures
          if procedure.RegistrationId is RegistrationId
            @parent.realms[@realm].registered_procedures.splice(index, 1)
            return @sendMessage(JSON.stringify [MESSAGE_TYPES.UNREGISTERED, RequestId])
        return @sendMessage(JSON.stringify [MESSAGE_TYPES.ERROR, MESSAGE_TYPES.UNREGISTER, RequestId, {}, 'wamp.error.no_such_registration'])
      when MESSAGE_TYPES.UNREGISTERED
        [RequestId] = arr.slice(1)
        console.log "Received Unregistered Message for RequestId: %s", RequestId
      when MESSAGE_TYPES.INVOCATION
        [RequestId, RegistrationId, OptionsDict, ArgumentsList, KwArguments]= arr.slice(1)
        console.log "Client received Invocation Message for registration id: #{RegistrationId} with arguments: %j", ArgumentsList
        for registration, index in @parent.registrations
          if registration.RegistrationId is RegistrationId
            #console.log "Invoking function '#{registration.uri}'"
            result = registration.fn.apply null, ArgumentsList, KwArguments
            #console.log "Result of invocation is: #{result}"
            @sendMessage(JSON.stringify([MESSAGE_TYPES.YIELD, RequestId, OptionsDict, [result]]))
            break
      when MESSAGE_TYPES.INTERRUPT
        console.log "Client received Interrupt Message"
      when MESSAGE_TYPES.YIELD
        console.log "Router received Yield Message from session #{@id}"
        [RequestId, OptionsDict, ArgumentsList, ArgumentsKwDict] = arr.slice(1)
        #console.log "Yield message data\nRequestId: #{RequestId}"
        #console.log "OptionsDict: %j", OptionsDict
        #console.log "ArgumentsList: #{ArgumentsList}"
        #console.log "ArgumentsKwDict: #{ArgumentsKwDict}"
        for invocation in @parent.realms[@realm].invocations
          if invocation.requestId is RequestId
            caller_sessionId = invocation.sessionId
            for session in @parent.realms[@realm].sessions
              if session.id is caller_sessionId
                caller_session = session
                result_message = [
                  MESSAGE_TYPES.RESULT,
                  RequestId,
                  OptionsDict,
                  ArgumentsList or [],
                  ArgumentsKwDict or {}
                ]
                #console.log "Sending results to session #{caller_session.id} corresponding to request Id: #{RequestId}"
                return caller_session.sendMessage(JSON.stringify result_message)
      else
        console.log "Unknown code received."


class WampClient extends events.EventEmitter

  constructor: (options) ->
    if (not options?.url) or (not options?.realm)
      throw new Error "Must provide a url and a realm to connect to"
    @[key] = value for key, value of options
    @roles = @roles or {subscriber: {}, publisher: {}, callee: {}, caller: {}}

  connect: =>
    @websocket = new ws.WebSocketClientConnection(@url)
    #return false unless @websocket.readyState is 'open'
    @websocket.on 'open', =>
      @peer = new WampPeer(@, @websocket, @roles)
      @websocket.on 'data', (opcode, data) =>
        @peer.processMessage(data)
      @peer.sendMessage(JSON.stringify [MESSAGE_TYPES.HELLO, @realm, @roles])
      true

  register: (uri, fn, options) =>
    reqId = @peer.nextId
    @peer.nextId += 1
    @registrations.push RequestId: reqId, uri: uri, fn: fn
    @peer.sendMessage(JSON.stringify [MESSAGE_TYPES.REGISTER, reqId, options or {}, uri])

  call: (procUri, args = [], kwArgs = {}, options = {}) =>
    reqId = @peer.nextId
    @peer.nextId += 1
    deferred = defer()
    callData = {RequestId: reqId, uri: procUri, args: args, kwArgs: kwArgs, options: options, deferred: deferred}
    @peer.calls.push callData
    @peer.sendMessage(JSON.stringify [MESSAGE_TYPES.CALL, reqId, options, procUri, args, kwArgs])
    deferred.promise()

  subscribe: (topic, handler, options = {}) ->
    reqId = @peer.nextId
    @peer.nextId += 1
    deferred = defer()
    subscriptionData = {RequestId: reqId, topic: topic, handler: handler, options: options, deferred: deferred}
    @peer.subscriptions.push subscriptionData
    @peer.sendMessage(JSON.stringify [MESSAGE_TYPES.SUBSCRIBE, reqId, options, topic])
    deferred.promise()

  publish: (topic, args = [], kwArgs = {}, options = {}) =>
    reqId = @peer.nextId
    @peer.nextId += 1
    deferred = defer()
    publicationData = {RequestId: reqId, topic: topic, args: args, kwArgs: kwArgs, options: options, deferred: deferred}
    @peer.publications.push publicationData
    @peer.sendMessage(JSON.stringify [MESSAGE_TYPES.PUBLISH, reqId, options, topic, args, kwArgs])
    deferred.promise()


class WampRouter extends events.EventEmitter
  _webSocketHandler: (websocket) =>
    websocket.peer = new WampPeer @, websocket, @roles
    websocket.on 'open', =>
      console.log "WebSocket opened"
    websocket.on 'data', (opcode, data) =>
      websocket.peer.processMessage(data)
    #websocket.on 'heartbeat', (roundTrip, pongTimeMillis) =>
    #  websocket.peer.processMessage()
    websocket.on 'close', (code, reason) =>
      console.log "Websocket closed. Close event data:\n Code: #{code or 'no data'} - Reason: #{reason or 'no data'}"

  constructor: (options) ->
    @_options = options or {}
    @roles = @_options.roles or {broker: {}, dealer: {}}

    @nextSessionId = genId()
    @realms = {}

    @webSocketServer = ws.createWebSocketServer(@_webSocketHandler)

   listen: (port, host = '0.0.0.0', route = '/wamp') =>
     @webSocketServer.listen port, host, route


createWampRouter = ->
  new WampRouter


test = ->
  wampRouter = createWampRouter()
  wampRouter.listen 8000, '0.0.0.0', '/'
  console.log "WAMP Router listening on port 8000"


module?.exports = {MESSAGE_TYPES, TRANSPORT_TYPES, WampPeer, WampClient, WampRouter, createWampRouter}

test() if not module?.parent