HttpFp

Functional http client in Ruby.

Usage

Basics

The Request Structure

In order to query an HTTP server you will need to build a request hash.

Here's an example of a request:

{:proto=>"HTTP/1.1",
 :host=>"http://api.github.com",
 :path=>"/users/martinos/repos",
 :query=>{},
 :header=>
  {"accept"=>"application/json",
   "Content-Type"=>"application/json",
   "user-agent"=>"paw/3.0.11 (macintosh; os x/10.11.6) gcdhttprequest"},
 :method=>"GET",
 :body=>""}

To build that request you can use builder functions and the function composition operator (>>~). Every builder function adds values to the response object. Example:

query = verb.("get") >>~ 
        with_path.("/users/martinos/repos") >>~ 
        with_host.("https://api.github.com") >>~ 
        add_headers.(json_headers)

The query variable is a builder function that is created by combining multiple builder functions together.

This query function takes a hash as a parameter, and returns a hash decorated by the builders.

To demonstrate how it works, we need an initialized request (empty_req). Here's the empty_req:

pp empty_req
# => 
{:proto=>"HTTP/1.1",
 :host=>"http://example.com",
 :path=>"/",
 :query=>{},
 :header=>{},
 :method=>"GET",
 :body=>""}

<<<<<<< HEAD We apply the empty_req to the query that we've built.

pp query.(empty_req)
# => 
{:proto=>"HTTP/1.1",
 :host=>"https://api.github.com",
 :path=>"/users/martinos/repos",
 :query=>{},
 :header=>
  {"accept"=>"application/json",
   "Content-Type"=>"application/json",
   "user-agent"=>"paw/3.0.11 (macintosh; os x/10.11.6) gcdhttprequest"},
 :method=>"GET",
 :body=>""}

In order to run the query, you can combine the query with a "server" function (lambda) that takes a "request", sends it to the server and returns a http "response".

HttpFp::NetHttp.server.(query.(empty_req))

# => 
{:status=>"200",
 :header=>
  {"server"=>["GitHub.com"],
   "date"=>["Sun, 04 Jun 2017 02:20:05 GMT"],
   "content-type"=>["application/json; charset=utf-8"],
   "vary"=>["Accept", "Accept-Encoding"], 
    ...},
  }
 :body => "{...}"
}

You can also use the pipe operator (>>+) and the run function. The run_ function takes a function as parameter and applies the empty_req to it.

Here is it's definition:

run_ = -> fn { fn.(empty_req) }

query >>~ HttpFp::NetHttp.server >>+ run_

Contributing

Fork it ( https://github.com/martinos/http_fp/fork )
Create your feature branch (git checkout -b my-new-feature)
Commit your changes (git commit -am 'Add some feature')
Push to the branch (git push origin my-new-feature)
Create a new Pull Request