How to post to a users wall from inside Rails model - ruby-on-rails-3

Question

My application gets approved and a user gets an access token and extended permissions which include offline_access and publish_stream.
I want to be able to post from inside my model. This would require me to make an
https://graph.facebook.com/FBUSER_ID/feed
plus some parameters and access token, app_id, app_secret.
I have the access token and FBUSER_ID.
What I don't know how to do is put it all together in the model.
Could anyone point me in the right direction?
I already have a facebook application. I need to know how to post from the server to a users wall
**Thanks to the answer below I was able to get it working with the following:
access_token = "AAACvmqy1nYoBAAZCkGXbVgRwcBv******ZAMjsLxKxR7DaZBE0NxY8ZBGBW1q2mzsB9TDT0RvgeQcDdnyFJNAYRf0icnhlbikZD"
appID = '1776938807888574888888888882'
message = 'test_message'
userID = '75164088804088888'
uri = URI.parse("https://graph.facebook.com/#{userID}/feed")
req = Net::HTTP::Post.new(uri.path)
result = req.set_form_data({:access_token => access_token , :message => message, :app_id => appID })
sock = Net::HTTP.new(uri.host, 443)
sock.use_ssl = true
sock.start do |http|
response = http.request(req)
end
IMPORTANT: at the top of the controller or model add:
require 'openssl'

Answer 1

First you have to create a Facebook application here. By the app_id and app_secret of created application, you will ask user to give "publishing feed" permission to your application. While getting this permissions you get also the access token for posting the users wall.
You can get detailed info about authentication here:
https://developers.facebook.com/docs/authentication/
And you can get info about publishing here on the Publishing section:
http://developers.facebook.com/docs/reference/api/
With ruby, your need is just making an HTTP Post. This may be an example for this:
Net::HTTP.post_form(URI.parse('https://graph.facebook.com/FBUSER_ID/feed'),
{'access_token' => 'ACCESS_TOKEN', 'message' => 'MESSAGE'})