145 lines
4.8 KiB
Python
145 lines
4.8 KiB
Python
"""Config file parser and config file generator.
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Configuration values will be read from a file called <CONFIG_FILE>.
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A config file with default values can be generated by running this module as a
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script and using the --generate option.
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The config file is a standard INI file that contains [sections] and options.
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Variables that are between %(option)s are interpolated automatically by the
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ConfigParser (with the caveat that they have to be in the same section).
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Variables that are between ${section:option} will be interpolated with the
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value from the appropriate section (similar to the way ConfigParse from
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Python3 works).
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Example of a config file:
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E.g.
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[Section1]
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key_1 = value 1
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key_2 = value 2
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country = mexico
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[section2]
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name = John
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lastname = Doe
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fullname = %(name)s %(lastname)s
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country = ${Section1:country}
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To access config values from other modules follow this approach:
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import Config.config as CONF
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full_name = CONF.get('section2', 'fullname')
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"""
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from __future__ import print_function
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import argparse
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import configparser
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import os
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import re
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CONFIG_FILE = os.path.join(os.path.dirname(__file__), 'config.ini')
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CONFIG = configparser.SafeConfigParser()
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def get(section, option, raw=False, variables=None):
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"""Wrapper function to mimic behavior of ConfigParse (Python3).
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Python3 uses a ConfigParse that is different than the Python2 ConfigParser,
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it has some additional functionality. One of the biggest differences is
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that with ConfigParse you can interpolate variables from one section into
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another section of the config file. This functionality is not included in
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the ConfigParse. Since it is very useful, this function wraps the original
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get function from ConfigParser so it includes the missing interpolation.
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:param section: the section where the option to be gotten is
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:param option: the option to look for in the config file
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:param raw: all the '%' interpolations are expanded in the return values,
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unless the raw argument is true.
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:param variables: the option is looked up in variables (if provided)
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:return: the specified value from the config file
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"""
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# ensure file readed is up to date always
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CONFIG.read(CONFIG_FILE)
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original_option = CONFIG.get(section, option, raw=raw, vars=variables)
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# find all matches that have the following pattern: ${something}
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matches = re.findall(r'\$\{(.*?)\}', original_option)
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new_value = original_option
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for match in matches:
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# interpolate matches found with ${something} with the referenced
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# option from the appropriate section
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pattern = '${' + match + '}'
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value = match.split(':')
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foreign_value = CONFIG.get(value[0], value[1])
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new_value = new_value.replace(pattern, foreign_value)
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if original_option != new_value:
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CONFIG.set(section, option, new_value)
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# return the interpolated value
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return CONFIG.get(section, option, raw=raw, vars=variables)
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def getint(section, option):
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"""Wrapper that returns the value as an integer.
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:param section: the section where the option to be gotten is
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:param option: the option to look for in the config file
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:return: the specified value from the config file
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"""
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return int(CONFIG.get(section, option))
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def getfloat(section, option):
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"""Wrapper that returns the value as a float.
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:param section: the section where the option to be gotten is
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:param option: the option to look for in the config file
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:return: the specified value from the config file
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"""
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return float(CONFIG.get(section, option))
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def getboolean(section, option):
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"""Wrapper that returns the value as a boolean.
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:param section: the section where the option to be gotten is
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:param option: the option to look for in the config file
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:return: the specified value from the config file
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"""
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value = CONFIG.get(section, option)
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return value.lower() == 'true'
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def _unload_current_values():
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"""Removes current sections from the existing config object"""
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for section in CONFIG.sections():
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CONFIG.remove_section(section)
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def create_config():
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"""Creates the config file in the current directory"""
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if os.path.isfile(CONFIG_FILE):
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os.remove(CONFIG_FILE)
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with open(CONFIG_FILE, 'wb') as configfile:
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_unload_current_values()
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CONFIG.write(configfile)
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def parse_arguments():
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"""Parses arguments from the command line"""
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parser = argparse.ArgumentParser(
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description='Config file generator')
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parser.add_argument(
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'--generate', action='store_true',
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help='Generates a config file with default values')
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return parser.parse_args()
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if __name__ == '__main__':
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ARGUMENTS = parse_arguments()
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if ARGUMENTS.generate:
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create_config()
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print('Config file created at: {name}'.format(name=CONFIG_FILE))
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