MessagePack

msg_pack.rb

# -*- encoding: utf-8 -*-
require 'msgpack'    unless defined?(::MessagePack)
require 'bigdecimal' unless defined?(::BigDecimal)
require 'time'       unless Time.respond_to?(:parse)

class BigDecimal
  def to_msgpack_ext
    [to_s].pack('A*')
  end

  def self.from_msgpack_ext(data) # 对 String 还挺友好的，排挤 Float
    self.new data.unpack('A*').first
  end
end

class Time
  def to_msgpack_ext # to_i 不够精确
    [xmlschema(9)].pack('A*') # yaml 保留 9位，json 只保留 3位
  end

  def self.from_msgpack_ext(data)
    self.parse data.unpack('A*').first
  end
end

class String
  def as_msgpack
    MessagePack.unpack(self)
  end
end

MessagePack::DefaultFactory.register_type(0x00, Symbol)
MessagePack::DefaultFactory.register_type(0x01, Time)
MessagePack::DefaultFactory.register_type(0x02, BigDecimal)
# 如果是汉字，会变增量
a = { created_at: Time.now, id: 123, price: 10.239, rate: BigDecimal('1.05'), title: 'haha你好haha'}
b = a.to_msgpack
c = b.as_msgpack

a.to_yaml == c.to_yaml