Accessing via Proxy in net/http

Accessing via Proxy

Net::HTTP.Proxy creates http proxy class. It has same methods of Net::HTTP but its instances always connect to proxy, instead of given host.

require 'net/http'

    proxy_addr = 'your.proxy.host'
    proxy_port = 8080
            :
    Net::HTTP::Proxy(proxy_addr, proxy_port).start('www.example.com') {|http|
      # always connect to your.proxy.addr:8080
            :
    }

Since Net::HTTP.Proxy returns Net::HTTP itself when proxy_addr is nil, there‘s no need to change code if there‘s proxy or not.
There are two additional parameters in Net::HTTP.Proxy which allow to specify proxy user name and password:

Net::HTTP::Proxy(proxy_addr, proxy_port, proxy_user = nil, proxy_pass = nil)

You may use them to work with authorization-enabled proxies:

require 'net/http'
    require 'uri'

    proxy_host = 'your.proxy.host'
    proxy_port = 8080
    uri = URI.parse(ENV['http_proxy'])
    proxy_user, proxy_pass = uri.userinfo.split(/:/) if uri.userinfo
    Net::HTTP::Proxy(proxy_host, proxy_port,
                     proxy_user, proxy_pass).start('www.example.com') {|http|
      # always connect to your.proxy.addr:8080 using specified username and password
            :
    }

Note that net/http never rely on HTTP_PROXY environment variable. If you want to use proxy, set it explicitly.