config.py

import json


class NestedConfig:
    def __init__(self, name, data):
        self.__dict__['name'] = name
        self.__dict__['data'] = data

    def __getattr__(self, key):
        return self.data.get(key)

    def __setattr__(self, key, value):
        self.data[key] = value

    def __len__(self):
        return len(self.__dict__['data'])

    def __repr__(self):
        return json.dumps(self.data, indent=4)

class ConfigMgr:
    def __init__(self):
        self._initialised = False

    def _load_option(self):
        self._initialised = True  # prevent infinite loop
        self.options = {}

        # Initialise defaults
        n = self.__getattr__('network')
        n.proxy = None
        n.retries = 0
        n.cache_ttl = 60     # seconds to reuse cached GET responses; 0 = no caching, None = never expire
        d = self.__getattr__('debug')
        d.hide_exceptions = True
        d.logging = False
        loc = self.__getattr__('locale')
        loc.lang = "en-US"   # BCP-47 language tag for Yahoo v7/v10 endpoints
        loc.region = "US"    # ISO 3166-1 alpha-2 country code

    def __getattr__(self, key):
        if not self._initialised:
            self._load_option()

        if key not in self.options:
            self.options[key] = {}
        return NestedConfig(key, self.options[key])

    def __contains__(self, key):
        if not self._initialised:
            self._load_option()

        return key in self.options

    def __repr__(self):
        if not self._initialised:
            self._load_option()

        all_options = self.options.copy()
        return json.dumps(all_options, indent=4)

YfConfig = ConfigMgr()