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         self.args[name] = default

    13 

    14     def load(self, fname):

    15         # parse config file

    16         with open(fname) as f:

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

    18         # check contents

    19         return self.check()

    20 

    21     def check(self):

    22         ok = True

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

    24             if key == '__builtins__':

    25                 continue

    26             if key in self.registered_args:

    27                 # arg registered, check type

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

    29                 if not isinstance(self.args[key], type) and not self.args[key] is None:

    30                     ok = False

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

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

    33             else:

    34                 # arg not registered

    35                 ok = False

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

    37         return ok

    38 

    39     def __getattr__(self, name):

    40         if name in self.args:

    41             return self.args[name]

    42 

    43         # raise error if not found

    44         raise AttributeError()

    45