# class MCollective::Message

container for a message, its headers, agent, collective and other meta data

### Constants

VALIDTYPES

### Attributes

agent[RW]
collective[RW]
discovered_hosts[RW]
expected_msgid[R]
filter[RW]
headers[RW]
message[R]
msgtime[R]
options[RW]
payload[R]
reply_to[R]
request[R]
requestid[RW]
ttl[RW]
type[R]
validated[R]

### Public Class Methods

new(payload, message, options = {}) click to toggle source

payload - the message body without headers etc, just the text message - the original message received from the middleware options - if the body base64 encoded? options - the agent the message is for/from options - the collective its for/from options - the message headers options - an indicator about the type of message, :message, :request, :direct_request or :reply options - if this is a reply this should old the message we are replying to options - for requests, the filter to encode into the message options - the normal client options hash options - the maximum amount of seconds this message can be valid for options - in the case of replies this is the msgid it is expecting in the replies options - specific request id to use else one will be generated

    # File lib/mcollective/message.rb, line 23
    def initialize(payload, message, options = {})
      options = {:base64 => false,
                 :agent => nil,
                 :headers => {},
                 :type => :message,
                 :request => nil,
                 :filter => Util.empty_filter,
                 :options => {},
                 :ttl => 60,
                 :expected_msgid => nil,
                 :requestid => nil,
                 :collective => nil}.merge(options)

      @payload = payload
      @message = message
      @requestid = options[:requestid]
      @discovered_hosts = nil
      @reply_to = nil

      @type = options[:type]
      @headers = options[:headers]
      @base64 = options[:base64]
      @filter = options[:filter]
      @expected_msgid = options[:expected_msgid]
      @options = options[:options]

      @ttl = @options[:ttl] || Config.instance.ttl
      @msgtime = 0

      @validated = false

      if options[:request]
        @request = options[:request]
        @agent = request.agent
        @collective = request.collective
        @type = :reply
      else
        @agent = options[:agent]
        @collective = options[:collective]
      end

      base64_decode!
    end

### Public Instance Methods

base64?() click to toggle source

    # File lib/mcollective/message.rb, line 129
    def base64?
      @base64
    end

base64_decode!() click to toggle source

    # File lib/mcollective/message.rb, line 115
    def base64_decode!
      return unless @base64

      @payload = SSL.base64_decode(@payload)
      @base64 = false
    end

base64_encode!() click to toggle source

    # File lib/mcollective/message.rb, line 122
    def base64_encode!
      return if @base64

      @payload = SSL.base64_encode(@payload)
      @base64 = true
    end

create_reqid() click to toggle source

    # File lib/mcollective/message.rb, line 235
    def create_reqid
      # we gsub out the -s so that the format of the id does not
      # change from previous versions, these should just be more
      # unique than previous ones
      SSL.uuid.gsub("-", "")
    end

decode!() click to toggle source

    # File lib/mcollective/message.rb, line 179
    def decode!
      raise "Cannot decode message type #{type}" unless [:request, :reply].include?(type)

      @payload = PluginManager["security_plugin"].decodemsg(self)

      if type == :request
        raise 'callerid in request is not valid, surpressing reply to potentially forged request' unless PluginManager["security_plugin"].valid_callerid?(payload[:callerid])
      end

      [:collective, :agent, :filter, :requestid, :ttl, :msgtime].each do |prop|
        instance_variable_set("@#{prop}", payload[prop]) if payload.include?(prop)
      end
    end

encode!() click to toggle source

    # File lib/mcollective/message.rb, line 133
    def encode!
      case type
        when :reply
          raise "Cannot encode a reply message if no request has been associated with it" unless request
          raise 'callerid in original request is not valid, surpressing reply to potentially forged request' unless PluginManager["security_plugin"].valid_callerid?(request.payload[:callerid])

          @requestid = request.payload[:requestid]
          @payload = PluginManager["security_plugin"].encodereply(agent, payload, requestid, request.payload[:callerid])
        when :request, :direct_request
          validate_compount_filter(@filter["compound"]) unless @filter["compound"].empty?

          @requestid = create_reqid unless @requestid
          @payload = PluginManager["security_plugin"].encoderequest(Config.instance.identity, payload, requestid, filter, agent, collective, ttl)
        else
          raise "Cannot encode #{type} messages"
      end
    end

expected_msgid=(msgid) click to toggle source

in the case of reply messages we are expecting replies to a previously created message. This stores a hint to that previously sent message id and can be used by other classes like the security plugins as a means of optimizing their behavior like by ignoring messages not directed at us.

    # File lib/mcollective/message.rb, line 110
    def expected_msgid=(msgid)
      raise "Can only store the expected msgid for reply messages" unless @type == :reply
      @expected_msgid = msgid
    end

publish() click to toggle source

publish a reply message by creating a target name and sending it

    # File lib/mcollective/message.rb, line 217
    def publish
      Timeout.timeout(2) do
        # If we've been specificaly told about hosts that were discovered
        # use that information to do P2P calls if appropriate else just
        # send it as is.
        if @discovered_hosts && Config.instance.direct_addressing
          if @discovered_hosts.size <= Config.instance.direct_addressing_threshold
            self.type = :direct_request
            Log.debug("Handling #{requestid} as a direct request")
          end

          PluginManager["connector_plugin"].publish(self)
        else
          PluginManager["connector_plugin"].publish(self)
        end
      end
    end

reply_to=(target) click to toggle source

Sets a custom reply-to target for requests. The connector plugin should inspect this when constructing requests and set this header ensuring replies will go to the custom target otherwise the connector should just do what it usually does

    # File lib/mcollective/message.rb, line 99
    def reply_to=(target)
      raise "Custom reply targets can only be set on requests" unless [:request, :direct_request].include?(@type)

      @reply_to = target
    end

type=(type) click to toggle source

Sets the message type to one of the known types. In the case of :direct_request the list of hosts to communicate with should have been set with discovered_hosts else an exception will be raised. This is for extra security, we never accidentally want to send a direct request without a list of hosts or something weird like that as it might result in a filterless broadcast being sent.

Additionally you simply cannot set :direct_request if direct_addressing was not enabled this is to force a workflow that doesnt not yield in a mistake when someone might assume direct_addressing is enabled when its not.

    # File lib/mcollective/message.rb, line 76
    def type=(type)
      raise "Unknown message type #{type}" unless VALIDTYPES.include?(type)

      if type == :direct_request
        raise "Direct requests is not enabled using the direct_addressing config option" unless Config.instance.direct_addressing

        unless @discovered_hosts && !@discovered_hosts.empty?
          raise "Can only set type to :direct_request if discovered_hosts have been set"
        end

        # clear out the filter, custom discovery sources might interpret the filters
        # different than the remote mcollectived and in directed mode really the only
        # filter that matters is the agent filter
        @filter = Util.empty_filter
        @filter["agent"] << @agent
      end

      @type = type
    end

validate() click to toggle source

Perform validation against the message by checking filters and ttl

    # File lib/mcollective/message.rb, line 194
    def validate
      raise "Can only validate request messages" unless type == :request

      msg_age = Time.now.utc.to_i - msgtime

      if msg_age > ttl
        cid = ""
        cid += payload[:callerid] + "@" if payload.include?(:callerid)
        cid += payload[:senderid]

        if msg_age > ttl
          PluginManager["global_stats"].ttlexpired

          raise(MsgTTLExpired, "Message #{requestid} from #{cid} created at #{msgtime} is #{msg_age} seconds old, TTL is #{ttl}")
        end
      end

      raise(NotTargettedAtUs, "Received message is not targetted to us") unless PluginManager["security_plugin"].validate_filter?(payload[:filter])

      @validated = true
    end

validate_compount_filter(compound_filter) click to toggle source

    # File lib/mcollective/message.rb, line 151
    def validate_compount_filter(compound_filter)
      compound_filter.each do |filter|
        filter.each do |statement|
          if statement["fstatement"]
            functionname = statement["fstatement"]["name"]
            pluginname = Data.pluginname(functionname)
            value = statement["fstatement"]["value"]

            begin
              ddl = DDL.new(pluginname, :data)
            rescue
              raise DDLValidationError, "Could not find DDL for data plugin #{pluginname}, cannot use #{functionname}() in discovery"
            end

            # parses numbers and booleans entered as strings into proper
            # types of data so that DDL validation will pass
            statement["fstatement"]["params"] = Data.ddl_transform_input(ddl, statement["fstatement"]["params"])

            Data.ddl_validate(ddl, statement["fstatement"]["params"])

            unless value && Data.ddl_has_output?(ddl, value)
              raise DDLValidationError, "#{functionname}() does not return a #{value} value"
            end
          end
        end
      end
    end