How to web programming with D2?

[canalpay]

I am trying to write the web framework(but not to write, to gain experience.). Maybe the framework can has got a MVC  desing pattern. But first, the D2 is not has got for the web library and I am decided write to library for web.

I am writed a function for post and get methods. (I am not tried to functions. But I think, they are works.)
POST: https://github.com/canalpay/turna/blob/master/library/post.d
GET  :  https://github.com/canalpay/turna/blob/master/library/get.d

Environment variables are easy to write for the function.
But How to write a cookie and session?
I looked at the codes of tango. However, don't understand.(I'm new to d programming language.)