gistfile1.rb

require 'sinatra'
require 'rest-client'
require 'digest/sha1'


set :bind, '0.0.0.0'
set :port, 59898

 get '/' do
    content_type 'text/xml'
    response = RestClient.post(
        "https://eapi.privatbank.ua/settlement/xml",
          {
            merchid: params[:merchid],
            date: params[:date],
            signature: Digest::SHA1.base64digest("#{params[:password]}#{params[:merchid]}#{params[:date]}")
          }
        )
 end