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# IVLE - Informatics Virtual Learning Environment
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# Copyright (C) 2007-2009 The University of Melbourne
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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# Author: Matt Giuca, Will Grant
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Provides programmatic access to the IVLE configuration file.
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from configobj import ConfigObj
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from validate import Validator
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__all__ = ["ConfigError", "Config"]
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class ConfigError(Exception):
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An error reading or writing the configuration file.
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Search for the config file, and return the directory it is in.
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1. Environment var IVLECONF (path to directory)
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Raises a ConfigError on error.
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if 'IVLECONF' in os.environ:
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fname = os.path.join(os.environ['IVLECONF'])
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if os.path.exists(fname):
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if os.path.exists('/etc/ivle'):
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raise ConfigError("Could not find IVLE config directory")
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def get_plugin(pluginstr):
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plugin_path, classname = pluginstr.split('#')
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# Load the plugin module from somewhere in the Python path
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# (Note that plugin_path is a fully-qualified Python module name).
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getattr(__import__(plugin_path, fromlist=[classname]), classname))
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class Config(ConfigObj):
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The configuration object. Can be instantiated with no arguments (will
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implicitly find the ivle.conf file and load it).
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Automatically validates the file against the spec (found in
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./ivle-spec.conf relative to this module).
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def __init__(self, blank=False, plugins=True, *args, **kwargs):
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"""Initialises a new Config object. Searches for the config file,
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loads it, and validates it.
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@param blank: If blank=True, will create a blank config instead, and
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not search for the config file.
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@param plugins: If True, will find and index plugins.
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@raise ConfigError: If the config file cannot be found.
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specfile = os.path.join(os.path.dirname(__file__), 'ivle-spec.conf')
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super(Config, self).__init__(configspec=specfile, *args, **kwargs)
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confdir = search_confdir()
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conffile = os.path.join(confdir, 'ivle.conf')
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super(Config, self).__init__(infile=conffile, configspec=specfile,
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# XXX This doesn't raise errors if it doesn't validate
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self.validate(Validator())
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self.plugin_configs = {}
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# Go through the plugin config files, looking for plugins.
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for pconfn in glob.glob(os.path.join(confdir, 'plugins.d/*.conf')):
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pconf = ConfigObj(pconfn)
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for plugin_section in pconf:
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# We have a plugin path. Resolve it into a class...
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plugin_path, plugin = get_plugin(plugin_section)
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self.plugins[plugin_path] = plugin
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# ... and add it to the registry.
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self.plugin_configs[plugin] = pconf[plugin_section]
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# Create a registry mapping plugin classes to paths.
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self.reverse_plugins = dict([(v, k) for (k, v) in
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self.plugins.items()])
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# Create an index of plugins by base class.
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self.plugin_index = {}
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for plugin in self.plugins.values():
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# Getmro returns a tuple of all the super-classes of the plugin
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for base in inspect.getmro(plugin):
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if base not in self.plugin_index:
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self.plugin_index[base] = []
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self.plugin_index[base].append(plugin)
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def set_by_path(self, path, value=_NO_VALUE, comment=None):
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"""Writes a value to an option, given a '/'-separated path.
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@param path: '/'-separated path to configuration option.
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@param value: Optional - value to write to the option.
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@param comment: Optional - comment string (lines separated by '\n's).
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Note: If only a comment is being inserted, and the value does not
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exist, fails silently.
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path = path.split('/')
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# Iterate over each segment of the path, and find the section in conf
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# file to insert the value into (use all but the last path segment)
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for seg in path[:-1]:
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# Create the section if it isn't there
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if seg not in conf_section:
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conf_section[seg] = {}
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conf_section = conf_section[seg]
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# The final path segment names the key to insert into
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if value is not _NO_VALUE:
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conf_section[keyname] = value
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if comment is not None:
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conf_section[keyname]
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conf_section.comments[keyname] = comment.split('\n')
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def get_by_path(self, path):
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"""Gets an option's value, given a '/'-separated path.
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@param path: '/'-separated path to configuration option.
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@raise KeyError: if no config option is at that path.
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# Iterate over each segment of the path, and find the value in conf file
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for seg in path.split('/'):
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value = value[seg] # May raise KeyError
added
removed
ivle/config/__init__.py
