module WebMockHTTPClients

def headers_from_session(uri)

the client session
some of the headers sent by HTTPClient are derived from 
def headers_from_session(uri)
  session_headers = HTTP::Message::Headers.new
  @session_manager.send(:open, uri).send(:set_header, MessageMock.new(session_headers))
  session_headers.all.inject({}) do |hdrs, header|
    hdrs[header[0]] = header[1]
    hdrs
  end
end