Date/Time Not actually in UTC about msgpack-ruby

[ndbroadbent]

+1, this just caused a bug in our sessions code that was really hard to track down. Other people have come across this too, see: https://github.com/fabrik42/acts_as_api/wiki/Support-custom-response-formats-(example-for-messagepack)

Finally, because MessagePack doesn't come with the ability to serialize a TimeWithZone, you need to monkey patch it in:

module ActiveSupport
  class TimeWithZone
   def to_msgpack(out='')
     self.to_s.to_msgpack(out)
   end
  end
end

I'll submit a pull request to automatically patch ActiveSupport::TimeWithZone if it is available.

[ndbroadbent]

Here's a little PoC, if you have a Rails console open:

pry(main)> time = Time.zone.now
#=> Thu, 21 Aug 2014 15:19:26 PDT -07:00

pry(main)> packed_time = MessagePack.pack(time)
#=> "\xB72014-08-21 15:19:26 UTC"

pry(main)> unpacked_time = MessagePack.unpack(packed_time)
#=> "2014-08-21 15:19:26 UTC"

pry(main)> Time.parse(unpacked_time)
#=> 2014-08-21 15:19:26 UTC

pry(main)> Time.zone.parse(unpacked_time)
#=> Thu, 21 Aug 2014 08:19:26 PDT -07:00

[cosmo0920]

Time serialization/deserialization is not supported current msgpack.
This feature will be supported by ext types of version v0.7.x.

Related to PR #90 discussions.

[tagomoris]

Now msgpack-ruby v0.7 supports ext types. So you can serialize Time (or Date) by code like below:

MessagePack::DefaultFactory.register_type(0x01, Time, packer: ->(t){ t.to_i.to_msgpack }, unpacker: ->(d){ Time.at(MessagePack.unpack(d)) })
t = Time.now
packed_time = MessagePack.pack(t)
MessagePack.unpack(packed_time) #=> 2015-11-08 13:33:59 +0900