cevdZddlZeZGddejZGddejZy)a Oslo.config's primary source of configuration data are plaintext, INI-like style, configuration files. With the addition of backend drivers support, it is possible to store configuration data in different places and with different formats, as long as there exists a proper driver to connect to those external sources and provide a way to fetch configuration values from them. A backend driver implementation is divided in two main classes, a driver class of type :class:`ConfigurationSourceDriver` and a configuration source class of type :class:`ConfigurationSource`. **IMPORTANT:** At this point, all backend drivers are only able to provide immutable values. This protects applications and services from having options in external sources mutated when they reload configuration files. NcXeZdZdZej dZej dZy)ConfigurationSourceDriveraA backend driver option for oslo.config. For each group name listed in **config_source** in the **DEFAULT** group, a :class:`ConfigurationSourceDriver` is responsible for creating one new instance of a :class:`ConfigurationSource`. The proper driver class to be used is selected based on the **driver** option inside each one of the groups listed in config_source and loaded through entry points managed by stevedore using the namespace oslo.config.driver:: [DEFAULT] config_source = source1 config_source = source2 ... [source1] driver = remote_file ... [source2] driver = castellan ... Each specific driver knows all the available options to properly instatiate a ConfigurationSource using the values comming from the given group in the open_source_from_opt_group() method and is able to generate sample config through the list_options_for_discovery() method. cy)aReturn an open configuration source. Uses group_name to find the configuration settings for the new source and then open the configuration source and return it. If a source cannot be open, raises an appropriate exception. :param conf: The active configuration option handler from which to seek configuration values. :type conf: ConfigOpts :param group_name: The configuration option group name where the options for the source are stored. :type group_name: str :returns: an instance of a subclass of ConfigurationSource N)selfconf group_names >/usr/lib/python3/dist-packages/oslo_config/sources/__init__.pyopen_source_from_opt_groupz4ConfigurationSourceDriver.open_source_from_opt_groupBcy)aReturn the list of options available to configure a new source. Drivers should advertise all supported options in this method for the purpose of sample generation by oslo-config-generator. For an example on how to implement this method you can check the **remote_file** driver at oslo_config.sources._uri.URIConfigurationSourceDriver. :returns: a list of supported options of a ConfigurationSource. Nr)rs r list_options_for_discoveryz4ConfigurationSourceDriver.list_options_for_discoveryTr r N)__name__ __module__ __qualname____doc__abcabstractmethodr rrr r rr$s;:   "     r r) metaclassc4eZdZdZej dZy)ConfigurationSourceaA configuration source option for oslo.config. A configuration source is able to fetch configuration values based on a (group, option) key from an external source that supports key-value mapping such as INI files, key-value stores, secret stores, and so on. cy)aReturn the value of the option from the group. :param group_name: Name of the group. :type group_name: str :param option_name: Name of the option. :type option_name: str :param opt: The option definition. :type opt: Opt :returns: A tuple (value, location) where value is the option value or oslo_config.sources._NoValue if the (group, option) is not present in the source, and location is a LocationInfo. Nr)rr option_nameopts r getzConfigurationSource.getlr r N)rrrrrrrrr r rrcs!     r r)rrobject_NoValueABCMetarrrr r r s9  8< #++< ~ CKK r