def request(action, url, headers, options = {})
headers['Expect'] ||= ''
req = Request.new
req.action = action
req.headers = self.headers.merge headers
req.timeout = options.fetch :timeout, self.timeout
req.connect_timeout = options.fetch :connect_timeout, self.connect_timeout
req.max_redirects = options.fetch :max_redirects, self.max_redirects
req.username = options.fetch :username, self.username
req.password = options.fetch :password, self.password
req.proxy = options.fetch :proxy, self.proxy
req.proxy_type = options.fetch :proxy_type, self.proxy_type
req.auth_type = options.fetch :auth_type, self.auth_type
req.insecure = options.fetch :insecure, self.insecure
req.ignore_content_length = options.fetch :ignore_content_length, self.ignore_content_length
req.buffer_size = options.fetch :buffer_size, self.buffer_size
req.multipart = options[:multipart]
req.upload_data = options[:data]
req.file_name = options[:file]
url = self.base_url.to_s + url.to_s
uri = URI.parse(url)
query = uri.query.to_s.split('&')
query += options[:query].is_a?(Hash) ? Util.build_query_pairs_from_hash(options[:query]) : options[:query].to_s.split('&')
uri.query = query.join('&')
uri.query = nil if uri.query.empty?
url = uri.to_s
raise ArgumentError, "Empty URL" if url.empty?
req.url = url
handle_request(req)
end