Ruby CGI + Oauth2 (facebook) Web Application Sample

facebookのOAuth2を使って、RubyのCGIウェブアプリケーションを認可するサンプルです。

Preparation

• Ruby CGI environment
• For example, Apache 2.2 and ruby 1.8.7
• facebook application ID and secret ID
• get from facebook developers site

Sequence

 

Code

login.rb

#!/usr/local/bin/ruby
require "cgi"

client_id    = "xxxxxxxx"  # set your facebook application client_id
redirect_uri = CGI.escape("http://myapp.com/top.rb") # set your application url

#
# 2. Redirect
#
url = "https://graph.facebook.com/oauth/authorize?" +
  "response_type=code&" +
  "client_id=#{client_id}&" +
  "redirect_uri=#{redirect_uri}"
cgi = CGI.new
print cgi.header({ 'status' => 'REDIRECT', 'Location' => url })

top.rb

#!/usr/local/bin/ruby
require 'rubygems'
require 'json'
require 'cgi'

client_id     = "xxxxxx"  # set your facebook application client_id
client_secret = "xxxxxx"  # set your facebook application client_secret
redirect_uri  = CGI.escape("http://myapp.com/top.rb")  # set your application url


#
# 5. Access Token Request
#
code = CGI.new()["code"]
url = "/oauth/access_token?" +
  "client_id=#{client_id}&" +
  "client_secret=#{client_secret}&" +
  "redirect_uri=#{redirect_uri}&"+
  "code=#{code}"

# start ssl
require 'net/https'
https = Net::HTTP.new('graph.facebook.com',443)
https.use_ssl = true
https.verify_mode = OpenSSL::SSL::VERIFY_NONE

access_token=""
https.start {
  response = https.get(url)
  # perse string such as  "access_token=AAAsZCLvBgZDZD&expires=4992995"
  response.body.split("&").each do |param|
    access_token = param.split("=")[1] if param.split("=")[0] == "access_token"
  end
}

#
# 7. Request User Information Using Access Token
#
json=""
url = "/me?access_token=#{access_token}"
https.start {
  json = https.get(url).body
}

#
# 9. User Infomation Page
#
name = JSON.parse(json)["name"]
print "Content-Type: text/html\n\nHello #{name}\n<hr>\n#{json}\n"