MessagePack (msgpack) is a system to serialize arbitrary structured data into a compact binary stream.
This page hosts a formal specification of MessagePack (msgpack) serialization format using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.
All parsing code for Ruby generated by Kaitai Struct depends on the Ruby runtime library. You have to install it before you can parse data.
The Ruby runtime library can be installed from RubyGems:
gem install kaitai-structParse a local file and get structure in memory:
data = Msgpack.from_file("path/to/local/file.bin")
Or parse structure from a string of bytes:
bytes = "\x00\x01\x02..."
data = Msgpack.new(Kaitai::Struct::Stream.new(bytes))
After that, one can get various attributes from the structure by invoking getter methods like:
data.b1 # => First byte is msgpack message is either a piece of data by
itself or determines types of further, more complex data
structures.
# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
require 'kaitai/struct/struct'
unless Gem::Version.new(Kaitai::Struct::VERSION) >= Gem::Version.new('0.9')
raise "Incompatible Kaitai Struct Ruby API: 0.9 or later is required, but you have #{Kaitai::Struct::VERSION}"
end
##
# MessagePack (msgpack) is a system to serialize arbitrary structured
# data into a compact binary stream.
# @see https://github.com/msgpack/msgpack/blob/master/spec.md Source
class Msgpack < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = self)
super(_io, _parent, _root)
_read
end
def _read
@b1 = @_io.read_u1
case b1
when 211
@int_extra = @_io.read_s8be
when 209
@int_extra = @_io.read_s2be
when 210
@int_extra = @_io.read_s4be
when 208
@int_extra = @_io.read_s1
when 205
@int_extra = @_io.read_u2be
when 207
@int_extra = @_io.read_u8be
when 204
@int_extra = @_io.read_u1
when 206
@int_extra = @_io.read_u4be
end
if is_float_32
@float_32_value = @_io.read_f4be
end
if is_float_64
@float_64_value = @_io.read_f8be
end
if is_str_8
@str_len_8 = @_io.read_u1
end
if is_str_16
@str_len_16 = @_io.read_u2be
end
if is_str_32
@str_len_32 = @_io.read_u4be
end
if is_str
@str_value = (@_io.read_bytes(str_len)).force_encoding("UTF-8")
end
if is_array_16
@num_array_elements_16 = @_io.read_u2be
end
if is_array_32
@num_array_elements_32 = @_io.read_u4be
end
if is_array
@array_elements = []
(num_array_elements).times { |i|
@array_elements << Msgpack.new(@_io)
}
end
if is_map_16
@num_map_elements_16 = @_io.read_u2be
end
if is_map_32
@num_map_elements_32 = @_io.read_u4be
end
if is_map
@map_elements = []
(num_map_elements).times { |i|
@map_elements << MapTuple.new(@_io, self, @_root)
}
end
self
end
class MapTuple < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = self)
super(_io, _parent, _root)
_read
end
def _read
@key = Msgpack.new(@_io)
@value = Msgpack.new(@_io)
self
end
attr_reader :key
attr_reader :value
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-array Source
def is_array_32
return @is_array_32 unless @is_array_32.nil?
@is_array_32 = b1 == 221
@is_array_32
end
def int_value
return @int_value unless @int_value.nil?
if is_int
@int_value = (is_pos_int7 ? pos_int7_value : (is_neg_int5 ? neg_int5_value : 4919))
end
@int_value
end
def str_len
return @str_len unless @str_len.nil?
if is_str
@str_len = (is_fix_str ? (b1 & 31) : (is_str_8 ? str_len_8 : (is_str_16 ? str_len_16 : str_len_32)))
end
@str_len
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-array Source
def is_fix_array
return @is_fix_array unless @is_fix_array.nil?
@is_fix_array = (b1 & 240) == 144
@is_fix_array
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-map Source
def is_map
return @is_map unless @is_map.nil?
@is_map = ((is_fix_map) || (is_map_16) || (is_map_32))
@is_map
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-array Source
def is_array
return @is_array unless @is_array.nil?
@is_array = ((is_fix_array) || (is_array_16) || (is_array_32))
@is_array
end
def is_float
return @is_float unless @is_float.nil?
@is_float = ((is_float_32) || (is_float_64))
@is_float
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-str Source
def is_str_8
return @is_str_8 unless @is_str_8.nil?
@is_str_8 = b1 == 217
@is_str_8
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-map Source
def is_fix_map
return @is_fix_map unless @is_fix_map.nil?
@is_fix_map = (b1 & 240) == 128
@is_fix_map
end
def is_int
return @is_int unless @is_int.nil?
@is_int = ((is_pos_int7) || (is_neg_int5))
@is_int
end
def is_bool
return @is_bool unless @is_bool.nil?
@is_bool = ((b1 == 194) || (b1 == 195))
@is_bool
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-str Source
def is_str_16
return @is_str_16 unless @is_str_16.nil?
@is_str_16 = b1 == 218
@is_str_16
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-float Source
def is_float_64
return @is_float_64 unless @is_float_64.nil?
@is_float_64 = b1 == 203
@is_float_64
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-map Source
def is_map_16
return @is_map_16 unless @is_map_16.nil?
@is_map_16 = b1 == 222
@is_map_16
end
def is_neg_int5
return @is_neg_int5 unless @is_neg_int5.nil?
@is_neg_int5 = (b1 & 224) == 224
@is_neg_int5
end
def pos_int7_value
return @pos_int7_value unless @pos_int7_value.nil?
if is_pos_int7
@pos_int7_value = b1
end
@pos_int7_value
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-nil Source
def is_nil
return @is_nil unless @is_nil.nil?
@is_nil = b1 == 192
@is_nil
end
def float_value
return @float_value unless @float_value.nil?
if is_float
@float_value = (is_float_32 ? float_32_value : float_64_value)
end
@float_value
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-array Source
def num_array_elements
return @num_array_elements unless @num_array_elements.nil?
if is_array
@num_array_elements = (is_fix_array ? (b1 & 15) : (is_array_16 ? num_array_elements_16 : num_array_elements_32))
end
@num_array_elements
end
def neg_int5_value
return @neg_int5_value unless @neg_int5_value.nil?
if is_neg_int5
@neg_int5_value = -((b1 & 31))
end
@neg_int5_value
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-bool Source
def bool_value
return @bool_value unless @bool_value.nil?
if is_bool
@bool_value = b1 == 195
end
@bool_value
end
def is_pos_int7
return @is_pos_int7 unless @is_pos_int7.nil?
@is_pos_int7 = (b1 & 128) == 0
@is_pos_int7
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-array Source
def is_array_16
return @is_array_16 unless @is_array_16.nil?
@is_array_16 = b1 == 220
@is_array_16
end
def is_str
return @is_str unless @is_str.nil?
@is_str = ((is_fix_str) || (is_str_8) || (is_str_16) || (is_str_32))
@is_str
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-str Source
def is_fix_str
return @is_fix_str unless @is_fix_str.nil?
@is_fix_str = (b1 & 224) == 160
@is_fix_str
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-str Source
def is_str_32
return @is_str_32 unless @is_str_32.nil?
@is_str_32 = b1 == 219
@is_str_32
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-map Source
def num_map_elements
return @num_map_elements unless @num_map_elements.nil?
if is_map
@num_map_elements = (is_fix_map ? (b1 & 15) : (is_map_16 ? num_map_elements_16 : num_map_elements_32))
end
@num_map_elements
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-float Source
def is_float_32
return @is_float_32 unless @is_float_32.nil?
@is_float_32 = b1 == 202
@is_float_32
end
##
# @see https://github.com/msgpack/msgpack/blob/master/spec.md#formats-map Source
def is_map_32
return @is_map_32 unless @is_map_32.nil?
@is_map_32 = b1 == 223
@is_map_32
end
##
# First byte is msgpack message is either a piece of data by
# itself or determines types of further, more complex data
# structures.
attr_reader :b1
attr_reader :int_extra
attr_reader :float_32_value
attr_reader :float_64_value
attr_reader :str_len_8
attr_reader :str_len_16
attr_reader :str_len_32
attr_reader :str_value
attr_reader :num_array_elements_16
attr_reader :num_array_elements_32
attr_reader :array_elements
attr_reader :num_map_elements_16
attr_reader :num_map_elements_32
attr_reader :map_elements
end