parameters: (realm, checkpassword, debug=False, accept_charset='utf-8')
docstring: A CherryPy tool which hooks at before_handler to perform
      HTTP Basic Access Authentication, as specified in :rfc:`2617`
      and :rfc:`7617`.
  
      If the request has an 'authorization' header with a 'Basic' scheme, this
      tool attempts to authenticate the credentials supplied in that header.  If
      the request has no 'authorization' header, or if it does but the scheme is
      not 'Basic', or if authentication fails, the tool sends a 401 response with
      a 'WWW-Authenticate' Basic header.
  
      realm
          A string containing the authentication realm.
  
      checkpassword
          A callable which checks the authentication credentials.
          Its signature is checkpassword(realm, username, password). where
          username and password are the values obtained from the request's
          'authorization' header.  If authentication succeeds, checkpassword
          returns True, else it returns False.
docstring_summary: A CherryPy tool which hooks at before_handler to perform
      HTTP Basic Access Authentication, as specified in :rfc:`2617`
      and :rfc:`7617`.
docstring_tokens: A CherryPy tool which hooks at before_handler to perform HTTP Basic Access Authentication as specified in : rfc : 2617 and : rfc : 7617 .
function: def basic_auth(realm, checkpassword, debug=False, accept_charset='utf-8'):
      """A CherryPy tool which hooks at before_handler to perform
      HTTP Basic Access Authentication, as specified in :rfc:`2617`
      and :rfc:`7617`.
  
      If the request has an 'authorization' header with a 'Basic' scheme, this
      tool attempts to authenticate the credentials supplied in that header.  If
      the request has no 'authorization' header, or if it does but the scheme is
      not 'Basic', or if authentication fails, the tool sends a 401 response with
      a 'WWW-Authenticate' Basic header.
  
      realm
          A string containing the authentication realm.
  
      checkpassword
          A callable which checks the authentication credentials.
          Its signature is checkpassword(realm, username, password). where
          username and password are the values obtained from the request's
          'authorization' header.  If authentication succeeds, checkpassword
          returns True, else it returns False.
  
      """
  
      fallback_charset = 'ISO-8859-1'
  
      if '"' in realm:
          raise ValueError('Realm cannot contain the " (quote) character.')
      request = cherrypy.serving.request
  
      auth_header = request.headers.get('authorization')
      if auth_header is not None:
          # split() error, base64.decodestring() error
          msg = 'Bad Request'
          with cherrypy.HTTPError.handle((ValueError, binascii.Error), 400, msg):
              scheme, params = auth_header.split(' ', 1)
              if scheme.lower() == 'basic':
                  charsets = accept_charset, fallback_charset
                  decoded_params = base64.b64decode(params.encode('ascii'))
                  decoded_params = _try_decode(decoded_params, charsets)
                  decoded_params = ntou(decoded_params)
                  decoded_params = unicodedata.normalize('NFC', decoded_params)
                  decoded_params = tonative(decoded_params)
                  username, password = decoded_params.split(':', 1)
                  if checkpassword(realm, username, password):
                      if debug:
                          cherrypy.log('Auth succeeded', 'TOOLS.AUTH_BASIC')
                      request.login = username
                      return  # successful authentication
  
      charset = accept_charset.upper()
      charset_declaration = (
          (', charset="%s"' % charset)
          if charset != fallback_charset
          else ''
      )
      # Respond with 401 status and a WWW-Authenticate header
      cherrypy.serving.response.headers['www-authenticate'] = (
          'Basic realm="%s"%s' % (realm, charset_declaration)
      )
      raise cherrypy.HTTPError(
          401, 'You are not authorized to access that resource')
function_tokens: def basic_auth ( realm , checkpassword , debug = False , accept_charset = 'utf-8' ) : fallback_charset = 'ISO-8859-1' if '"' in realm : raise ValueError ( 'Realm cannot contain the " (quote) character.' ) request = cherrypy . serving . request auth_header = request . headers . get ( 'authorization' ) if auth_header is not None : # split() error, base64.decodestring() error msg = 'Bad Request' with cherrypy . HTTPError . handle ( ( ValueError , binascii . Error ) , 400 , msg ) : scheme , params = auth_header . split ( ' ' , 1 ) if scheme . lower ( ) == 'basic' : charsets = accept_charset , fallback_charset decoded_params = base64 . b64decode ( params . encode ( 'ascii' ) ) decoded_params = _try_decode ( decoded_params , charsets ) decoded_params = ntou ( decoded_params ) decoded_params = unicodedata . normalize ( 'NFC' , decoded_params ) decoded_params = tonative ( decoded_params ) username , password = decoded_params . split ( ':' , 1 ) if checkpassword ( realm , username , password ) : if debug : cherrypy . log ( 'Auth succeeded' , 'TOOLS.AUTH_BASIC' ) request . login = username return # successful authentication charset = accept_charset . upper ( ) charset_declaration = ( ( ', charset="%s"' % charset ) if charset != fallback_charset else '' ) # Respond with 401 status and a WWW-Authenticate header cherrypy . serving . response . headers [ 'www-authenticate' ] = ( 'Basic realm="%s"%s' % ( realm , charset_declaration ) ) raise cherrypy . HTTPError ( 401 , 'You are not authorized to access that resource' )