An HTTP Proxy server which proxies GET, HEAD and POST requests.

To create a simple proxy server:

require 'webrick'
require 'webrick/httpproxy'

proxy = WEBrick::HTTPProxyServer.new Port: 8000

trap 'INT'  do proxy.shutdown end
trap 'TERM' do proxy.shutdown end

proxy.start

See ::new for proxy-specific configuration items.

Modifying proxied responses

To modify content the proxy server returns use the :ProxyContentHandler option:

handler = proc do |req, res|
  if res['content-type'] == 'text/plain' then
    res.body << "\nThis content was proxied!\n"
  end
end

proxy =
  WEBrick::HTTPProxyServer.new Port: 8000, ProxyContentHandler: handler
Methods
N
Class Public methods
new(config={}, default=Config::HTTP)

Proxy server configurations. The proxy server handles the following configuration items in addition to those supported by HTTPServer:

:ProxyAuthProc

Called with a request and response to authorize a request

:ProxyVia

Appended to the via header

:ProxyURI

The proxy server's URI

:ProxyContentHandler

Called with a request and response and allows modification of the response

:ProxyTimeout

Sets the proxy timeouts to 30 seconds for open and 60 seconds for read operations

Source: show | on GitHub 

# File lib/webrick/httpproxy.rb, line 85
def initialize(config={}, default=Config::HTTP)
  super(config, default)
  c = @config
  @via = "#{c[:HTTPVersion]} #{c[:ServerName]}:#{c[:Port]}"
end