1 import logging

     2 

     3 

     4 class ConfigParser:

     5     def __init__(self):

     6         self.args = {}       # config file arguments

     7         self.registered_args = {}

     8         self.log = logging.getLogger('config') 

     9 

    10     def add_argument(self, name, type=str, default=None):

    11         self.registered_args[name] = {'type':type, 'default':default}

    12 

    13     def load(self, fname):

    14         # parse config file

    15         with open(fname) as f:

    16             exec(f.read(), self.args)

    17         # check contents

    18         return self.check()

    19 

    20     def check(self):

    21         ok = True

    22         for key in self.args.keys():

    23             if key == '__builtins__':

    24                 continue

    25             if key in self.registered_args:

    26                 # arg registered, check type

    27                 type = self.registered_args[key]['type']

    28                 if not isinstance(self.args[key], type):

    29                     ok = False

    30                     self.log.error("Bad type of config parameter '%s': is %s but should be %s",

    31                         key, type(self.args[key]), type)

    32             else:

    33                 # arg not registered

    34                     ok = False

    35                     self.log.error("Unknown config parameter '%s'.", key)

    36         return ok

    37 

    38     def __getattr__(self, name):

    39         if name in self.args:

    40             return self.args[name]

    41         

    42         # raise error if not found

    43         raise AttributeError()

    44