import imp import os import errno import sys string_types = (str,) def get_config(): if get_config.instance is None: get_config.instance = Config(os.getcwd()) return get_config.instance get_config.instance = None ## Stolen from flask.config class Config(dict): """Works exactly like a dict but provides ways to fill it from files or special dictionaries. There are two common patterns to populate the config. Either you can fill the config from a config file:: app.config.from_pyfile('yourconfig.cfg') Or alternatively you can define the configuration options in the module that calls :meth:`from_object` or provide an import path to a module that should be loaded. It is also possible to tell it to use the same module and with that provide the configuration values just before the call:: DEBUG = True SECRET_KEY = 'development key' app.config.from_object(__name__) In both cases (loading from any Python file or loading from modules), only uppercase keys are added to the config. This makes it possible to use lowercase values in the config file for temporary values that are not added to the config or to define the config keys in the same file that implements the application. Probably the most interesting way to load configurations is from an environment variable pointing to a file:: app.config.from_envvar('YOURAPPLICATION_SETTINGS') In this case before launching the application you have to set this environment variable to the file you want to use. On Linux and OS X use the export statement:: export YOURAPPLICATION_SETTINGS='/path/to/config/file' On windows use `set` instead. :param root_path: path to which files are read relative from. When the config object is created by the application, this is the application's :attr:`~flask.Flask.root_path`. :param defaults: an optional dictionary of default values """ def __init__(self, root_path, defaults=None): dict.__init__(self, defaults or {}) self.root_path = root_path def from_envvar(self, variable_name, silent=False): """Loads a configuration from an environment variable pointing to a configuration file. This is basically just a shortcut with nicer error messages for this line of code:: app.config.from_pyfile(os.environ['YOURAPPLICATION_SETTINGS']) :param variable_name: name of the environment variable :param silent: set to `True` if you want silent failure for missing files. :return: bool. `True` if able to load config, `False` otherwise. """ rv = os.environ.get(variable_name) if not rv: if silent: return False raise RuntimeError('The environment variable %r is not set ' 'and as such configuration could not be ' 'loaded. Set this variable and make it ' 'point to a configuration file' % variable_name) return self.from_pyfile(rv, silent=silent) def from_pyfile(self, filename, silent=False): """Updates the values in the config from a Python file. This function behaves as if the file was imported as module with the :meth:`from_object` function. :param filename: the filename of the config. This can either be an absolute filename or a filename relative to the root path. :param silent: set to `True` if you want silent failure for missing files. .. versionadded:: 0.7 `silent` parameter. """ filename = os.path.join(self.root_path, filename) d = imp.new_module('config') d.__file__ = filename try: with open(filename) as config_file: exec(compile(config_file.read(), filename, 'exec'), d.__dict__) except IOError as e: if silent and e.errno in (errno.ENOENT, errno.EISDIR): return False e.strerror = 'Unable to load configuration file (%s)' % e.strerror raise self.from_object(d) return True def from_object(self, obj): """Updates the values from the given object. An object can be of one of the following two types: - a string: in this case the object with that name will be imported - an actual object reference: that object is used directly Objects are usually either modules or classes. Just the uppercase variables in that object are stored in the config. Example usage:: app.config.from_object('yourapplication.default_config') from yourapplication import default_config app.config.from_object(default_config) You should not use this function to load the actual configuration but rather configuration defaults. The actual config should be loaded with :meth:`from_pyfile` and ideally from a location not within the package because the package might be installed system wide. :param obj: an import name or object """ if isinstance(obj, string_types): obj = import_string(obj) for key in dir(obj): if key.isupper(): self[key] = getattr(obj, key) def __repr__(self): return '<%s %s>' % (self.__class__.__name__, dict.__repr__(self)) def import_string(import_name, silent=False): """Imports an object based on a string. This is useful if you want to use import paths as endpoints or something similar. An import path can be specified either in dotted notation (``xml.sax.saxutils.escape``) or with a colon as object delimiter (``xml.sax.saxutils:escape``). If `silent` is True the return value will be `None` if the import fails. :param import_name: the dotted name for the object to import. :param silent: if set to `True` import errors are ignored and `None` is returned instead. :return: imported object """ #XXX: py3 review needed assert isinstance(import_name, string_types) # force the import name to automatically convert to strings import_name = str(import_name) try: if ':' in import_name: module, obj = import_name.split(':', 1) elif '.' in import_name: module, obj = import_name.rsplit('.', 1) else: return __import__(import_name) # __import__ is not able to handle unicode strings in the fromlist # if the module is a package if sys.version_info[0] == 2 and isinstance(obj, unicode): obj = obj.encode('utf-8') try: return getattr(__import__(module, None, None, [obj]), obj) except (ImportError, AttributeError): # support importing modules not yet set up by the parent module # (or package for that matter) modname = module + '.' + obj __import__(modname) return sys.modules[modname] except ImportError as e: if not silent: raise e