Class: Fix::Engine::MessageBuffer

Inherits:
Object
  • Object
show all
Includes:
Logger
Defined in:
lib/fix/engine/message_buffer.rb

Overview

A FIX message to which fields get appended, once it is completed by a proper terminator it is handled

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Logger

#log, log, logger

Constructor Details

#initialize(&block) ⇒ MessageBuffer

Returns a new instance of MessageBuffer.



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# File 'lib/fix/engine/message_buffer.rb', line 16

def initialize(&block)
  @fields = []

  raise "A block accepting a FP::Message as single parameter must be provided" unless (block && (block.arity == 1))
  @msg_handler = block
end

Instance Attribute Details

#client ⇒ Object

Returns the value of attribute client.



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# File 'lib/fix/engine/message_buffer.rb', line 14

def client
  @client
end

#fields ⇒ Object

Returns the value of attribute fields.



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# File 'lib/fix/engine/message_buffer.rb', line 14

def fields
  @fields
end

Instance Method Details

#add_data(data) ⇒ Object

Adds received bytes to the message buffer and attempt to process them

Parameters:

  • data (String) —

    The received FIX message bits, as they come



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# File 'lib/fix/engine/message_buffer.rb', line 28

def add_data(data)
  msg_buf << data.chomp
  parse_messages
end

#append(fld) ⇒ Object

Append a single FIX field to the message

Parameters:

  • fld (String) —

    A FIX formatted field, such as “35=0x01”



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# File 'lib/fix/engine/message_buffer.rb', line 38

def append(fld)
  raise "Cannot append to complete message" if complete?
  field = fld.split('=')
  field[0] = field[0].to_i
  field[1] = field[1].gsub(/\x01\Z/, '')
  @fields << field
end

#complete? ⇒ Boolean

Returns true if the last field of the collection is a FIX checksum

Returns:

  • (Boolean) —

    Whether the message is complete



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# File 'lib/fix/engine/message_buffer.rb', line 51

def complete?
  (@fields.count > 0) && (@fields.last[0] == 10)
end

#debug ⇒ String

Returns a human-friendly string of the currently handled data

Returns:

  • (String) —

    The parsed fields and the temporary buffer



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# File 'lib/fix/engine/message_buffer.rb', line 84

def debug
  "#{to_s('|')}#{@msg_buf}"
end

#msg_buf ⇒ Object

The data buffer string



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# File 'lib/fix/engine/message_buffer.rb', line 75

def msg_buf
  @msg_buf ||= ''
end

#parse_messages(&block) ⇒ Object

Attempts to parse fields from the message buffer, if the fields that get parsed complete the temporary message, it is processed



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# File 'lib/fix/engine/message_buffer.rb', line 59

def parse_messages(&block)
  while idx = msg_buf.index("\x01")
    field = msg_buf.slice!(0, idx + 1).gsub(/\x01\Z/, '')
    append(field)

    if complete?
      parsed = FP.parse(to_s)
      @fields = []
      @msg_handler.call(parsed)
    end
  end
end

#to_s(sep = "\x01") ⇒ String

Returns the current fields as a string joined by a given separator

Parameters:

  • sep (String) (defaults to: "\x01") —

    The separator

Returns:

  • (String) —

    The fields joined by the separator



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# File 'lib/fix/engine/message_buffer.rb', line 94

def to_s(sep = "\x01")
  fields.map { |f| f.join('=') }.join(sep) + sep
end