Synnefo » ./kamaki

# Copyright 2011-2012 GRNET S.A. All rights reserved.

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# without modification, are permitted provided that the following

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#      disclaimer.

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#      disclaimer in the documentation and/or other materials

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import os

from collections import defaultdict

from ConfigParser import RawConfigParser, NoOptionError, NoSectionError

try:

    from collections import OrderedDict

except ImportError:

    from ordereddict import OrderedDict

# Path to the file that stores the configuration

CONFIG_PATH = os.path.expanduser('~/.kamakirc')

# Name of a shell variable to bypass the CONFIG_PATH value

CONFIG_ENV = 'KAMAKI_CONFIG'

HEADER = """

# Kamaki configuration file

"""

DEFAULTS = {

    'global': {

        'colors': 'on',

        'token': ''

    },

    'config': {

        'cli': 'config_cli',

        'description': 'Configuration commands'

    }

}

class Config(RawConfigParser):

    def __init__(self, path=None):

        RawConfigParser.__init__(self, dict_type=OrderedDict)

        self.path = path or os.environ.get(CONFIG_ENV, CONFIG_PATH)

        self._overrides = defaultdict(dict)

        self._load_defaults()

        self.read(self.path)

    def _load_defaults(self):

        for section, options in DEFAULTS.items():

            for option, val in options.items():

                self.set(section, option, val)

    def apis(self):

        return [api for api in self.sections() if api != 'global']

    def get(self, section, option):

        value = self._overrides.get(section, {}).get(option)

        if value is not None:

            return value

        try:

            return RawConfigParser.get(self, section, option)

        except (NoSectionError, NoOptionError):

            return DEFAULTS.get(section, {}).get(option)

    def set(self, section, option, value):

        if section not in RawConfigParser.sections(self):

            self.add_section(section)

        RawConfigParser.set(self, section, option, value)

    def remove_option(self, section, option):

        try:

            RawConfigParser.remove_option(self, section, option)

        except NoSectionError:

            pass

    def items(self, section, include_defaults=False):

        d = dict(DEFAULTS[section]) if include_defaults else {}

        try:

            d.update(RawConfigParser.items(self, section))

        except NoSectionError:

            pass

        return d.items()

    def override(self, section, option, value):

        self._overrides[section][option] = value

    def write(self):

        with open(self.path, 'w') as f:

            os.chmod(self.path, 0600)

            f.write(HEADER.lstrip())

            RawConfigParser.write(self, f)