# File lib/httpclient/auth.rb, line 671
    def initialize
      @config = nil # common config
      @auth = {} # configs for each site
      @challengeable = {}
      @nonce_count = 0
      @signature_handler = {
        'HMAC-SHA1' => method(:sign_hmac_sha1)
      }
      @scheme = "OAuth"
    end