[TIPS] WEBrick proxy server with Digest Auth

Well-known WEBrick proxy server with BASIC auth is as following:

auth_proc = Proc.new do |req,res|
  WEBrick::HTTPAuth.proxy_basic_auth(req,res,'proxy') do |user,pass|
    user == "user" && pass == "pass"
  end
end
server = WEBrick::HTTPProxyServer.new({
  :Port => 8080,
  :ProxyAuthProcess => auth_proc
})
Signal.trap("INT") do server.shutdown end
server.start

But There is not a DIGEST version of proxy_basic_auth() method...

Solution: Use WEBrick::HTTPAuth::ProxyDigestAuth:

require "webrick"
require "webrick/httpproxy"
require "webrick/httpauth/digestauth"
require "webrick/httpauth/basicauth"
require "webrick/httpauth/userdb"

userdb = Hash.new
userdb.extend(WEBrick::HTTPAuth::UserDB)
userdb.auth_type = WEBrick::HTTPAuth::ProxyDigestAuth # or WEBrick::HTTPAuth::ProxyBasicAuth
userdb.set_passwd("realm", "user", "pass")
authenticator = userdb.auth_type.new({
     :Realm => "realm",
     :UserDB => userdb,
     :Algorithm => "MD5",
})

auth_proc = Proc.new do |req,res|
    authenticator.authenticate(req, res)
end
server = WEBrick::HTTPProxyServer.new({
  :Port => 8080,
  :ProxyAuthProcess => auth_proc
})
Signal.trap("INT") do server.shutdown end
server.start