# -*- coding: utf-8 -*- ## This file is part of Gajim. ## ## Gajim is free software; you can redistribute it and/or modify ## it under the terms of the GNU General Public License as published ## by the Free Software Foundation; version 3 only. ## ## Gajim is distributed in the hope that it will be useful, ## but WITHOUT ANY WARRANTY; without even the implied warranty of ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ## GNU General Public License for more details. ## ## You should have received a copy of the GNU General Public License ## along with Gajim. If not, see . ## ''' Plug-in management related classes. :author: Mateusz Biliński :since: 30th May 2008 :copyright: Copyright (2008) Mateusz Biliński :license: GPL ''' __all__ = ['PluginManager'] import os import sys import fnmatch import zipfile from shutil import rmtree import configparser from pkg_resources import parse_version from common import gajim from common import nec from common.exceptions import PluginsystemError from plugins.helpers import log, log_calls, Singleton from plugins.helpers import GajimPluginActivateException from plugins.gajimplugin import GajimPlugin, GajimPluginException class PluginManager(metaclass=Singleton): ''' Main plug-in management class. Currently: - scans for plugins - activates them - handles GUI extension points, when called by GUI objects after plugin is activated (by dispatching info about call to handlers in plugins) :todo: add more info about how GUI extension points work :todo: add list of available GUI extension points :todo: implement mechanism to dynamically load plugins where GUI extension points have been already called (i.e. when plugin is activated after GUI object creation). [DONE?] :todo: implement mechanism to dynamically deactive plugins (call plugin's deactivation handler) [DONE?] :todo: when plug-in is deactivated all GUI extension points are removed from `PluginManager.gui_extension_points_handlers`. But when object that invoked GUI extension point is abandoned by Gajim, eg. closed ChatControl object, the reference to called GUI extension points is still in `PluginManager.gui_extension_points` These should be removed, so that object can be destroyed by Python. Possible solution: add call to clean up method in classes 'destructors' (classes that register GUI extension points) ''' __metaclass__ = Singleton #@log_calls('PluginManager') def __init__(self): self.plugins = [] ''' Detected plugin classes. Each class object in list is `GajimPlugin` subclass. :type: [] of class objects ''' self.active_plugins = [] ''' Instance objects of active plugins. These are object instances of classes held `plugins`, but only those that were activated. :type: [] of `GajimPlugin` based objects ''' self.gui_extension_points = {} ''' Registered GUI extension points. ''' self.gui_extension_points_handlers = {} ''' Registered handlers of GUI extension points. ''' self.encryption_plugins = {} ''' Registered names with instances of encryption Plugins. ''' for path in [gajim.PLUGINS_DIRS[1], gajim.PLUGINS_DIRS[0]]: pc = PluginManager.scan_dir_for_plugins(path) self.add_plugins(pc) self._activate_all_plugins_from_global_config() @log_calls('PluginManager') def _plugin_has_entry_in_global_config(self, plugin): if gajim.config.get_per('plugins', plugin.short_name) is None: return False else: return True @log_calls('PluginManager') def _create_plugin_entry_in_global_config(self, plugin): gajim.config.add_per('plugins', plugin.short_name) def _remove_plugin_entry_in_global_config(self, plugin): gajim.config.del_per('plugins', plugin.short_name) @log_calls('PluginManager') def add_plugin(self, plugin_class): ''' :todo: what about adding plug-ins that are already added? Module reload and adding class from reloaded module or ignoring adding plug-in? ''' plugin = plugin_class() if plugin not in self.plugins: if not self._plugin_has_entry_in_global_config(plugin): self._create_plugin_entry_in_global_config(plugin) self.plugins.append(plugin) plugin.active = False else: log.info('Not loading plugin %s v%s from module %s (identified by' ' short name: %s). Plugin already loaded.' % (plugin.name, plugin.version, plugin.__module__, plugin.short_name)) @log_calls('PluginManager') def add_plugins(self, plugin_classes): for plugin_class in plugin_classes: self.add_plugin(plugin_class) @log_calls('PluginManager') def get_active_plugin(self, plugin_name): for plugin in self.active_plugins: if plugin.short_name == plugin_name: return plugin return None @log_calls('PluginManager') def extension_point(self, gui_extpoint_name, *args): ''' Invokes all handlers (from plugins) for a particular extension point, but doesnt add it to collection for further processing. For example if you pass a message for encryption via extension point to a plugin, its undesired that the call is stored and replayed on activating the plugin. For example after an update. :param gui_extpoint_name: name of GUI extension point. :type gui_extpoint_name: str :param args: parameters to be passed to extension point handlers (typically and object that invokes `gui_extension_point`; however, this can be practically anything) :type args: tuple ''' self._execute_all_handlers_of_gui_extension_point(gui_extpoint_name, *args) @log_calls('PluginManager') def gui_extension_point(self, gui_extpoint_name, *args): ''' Invokes all handlers (from plugins) for particular GUI extension point and adds it to collection for further processing (eg. by plugins not active yet). :param gui_extpoint_name: name of GUI extension point. :type gui_extpoint_name: str :param args: parameters to be passed to extension point handlers (typically and object that invokes `gui_extension_point`; however, this can be practically anything) :type args: tuple :todo: GUI extension points must be documented well - names with parameters that will be passed to handlers (in plugins). Such documentation must be obeyed both in core and in plugins. This is a loosely coupled approach and is pretty natural in Python. :bug: what if only some handlers are successfully connected? we should revert all those connections that where successfully made. Maybe call 'self._deactivate_plugin()' or sth similar. Looking closer - we only rewrite tuples here. Real check should be made in method that invokes gui_extpoints handlers. ''' self._add_gui_extension_point_call_to_list(gui_extpoint_name, *args) self._execute_all_handlers_of_gui_extension_point(gui_extpoint_name, *args) @log_calls('PluginManager') def remove_gui_extension_point(self, gui_extpoint_name, *args): ''' Removes GUI extension point from collection held by `PluginManager`. From this point this particular extension point won't be visible to plugins (eg. it won't invoke any handlers when plugin is activated). GUI extension point is removed completely (there is no way to recover it from inside `PluginManager`). Removal is needed when instance object that given extension point was connect with is destroyed (eg. ChatControl is closed or context menu is hidden). Each `PluginManager.gui_extension_point` call should have a call of `PluginManager.remove_gui_extension_point` related to it. :note: in current implementation different arguments mean different extension points. The same arguments and the same name mean the same extension point. :todo: instead of using argument to identify which extpoint should be removed, maybe add additional 'id' argument - this would work similar hash in Python objects. 'id' would be calculated based on arguments passed or on anything else (even could be constant) This would give core developers (that add new extpoints) more freedom, but is this necessary? :param gui_extpoint_name: name of GUI extension point. :type gui_extpoint_name: str :param args: arguments that `PluginManager.gui_extension_point` was called with for this extension point. This is used (along with extension point name) to identify element to be removed. :type args: tuple ''' if gui_extpoint_name in self.gui_extension_points: extension_points = list(self.gui_extension_points[gui_extpoint_name]) for ext_point in extension_points: if args[0] in ext_point: self.gui_extension_points[gui_extpoint_name].remove( ext_point) @log_calls('PluginManager') def _add_gui_extension_point_call_to_list(self, gui_extpoint_name, *args): ''' Adds GUI extension point call to list of calls. This is done only if such call hasn't been added already (same extension point name and same arguments). :note: This is assumption that GUI extension points are different only if they have different name or different arguments. :param gui_extpoint_name: GUI extension point name used to identify it by plugins. :type gui_extpoint_name: str :param args: parameters to be passed to extension point handlers (typically and object that invokes `gui_extension_point`; however, this can be practically anything) :type args: tuple ''' if ((gui_extpoint_name not in self.gui_extension_points) or (args not in self.gui_extension_points[gui_extpoint_name])): self.gui_extension_points.setdefault(gui_extpoint_name,[]).append( args) @log_calls('PluginManager') def _execute_all_handlers_of_gui_extension_point(self, gui_extpoint_name, *args): if gui_extpoint_name in self.gui_extension_points_handlers: for handlers in self.gui_extension_points_handlers[ gui_extpoint_name]: try: handlers[0](*args) except Exception as e: log.warning('Error executing %s', handlers[0], exc_info=True) def _register_events_handlers_in_ged(self, plugin): for event_name, handler in plugin.events_handlers.items(): priority = handler[0] handler_function = handler[1] gajim.ged.register_event_handler(event_name, priority, handler_function) def _remove_events_handler_from_ged(self, plugin): for event_name, handler in plugin.events_handlers.items(): priority = handler[0] handler_function = handler[1] gajim.ged.remove_event_handler(event_name, priority, handler_function) def _register_network_events_in_nec(self, plugin): for event_class in plugin.events: setattr(event_class, 'plugin', plugin) if issubclass(event_class, nec.NetworkIncomingEvent): gajim.nec.register_incoming_event(event_class) elif issubclass(event_class, nec.NetworkOutgoingEvent): gajim.nec.register_outgoing_event(event_class) def _remove_network_events_from_nec(self, plugin): for event_class in plugin.events: if issubclass(event_class, nec.NetworkIncomingEvent): gajim.nec.unregister_incoming_event(event_class) elif issubclass(event_class, nec.NetworkOutgoingEvent): gajim.nec.unregister_outgoing_event(event_class) def _remove_name_from_encryption_plugins(self, plugin): if plugin.encryption_name: del self.encryption_plugins[plugin.encryption_name] @log_calls('PluginManager') def activate_plugin(self, plugin): ''' :param plugin: plugin to be activated :type plugin: class object of `GajimPlugin` subclass ''' if not plugin.active and plugin.activatable: self._add_gui_extension_points_handlers_from_plugin(plugin) self._add_encryption_name_from_plugin(plugin) self._handle_all_gui_extension_points_with_plugin(plugin) self._register_events_handlers_in_ged(plugin) self._register_network_events_in_nec(plugin) self.active_plugins.append(plugin) try: plugin.activate() except GajimPluginException as e: self.deactivate_plugin(plugin) raise GajimPluginActivateException(str(e)) self._set_plugin_active_in_global_config(plugin) plugin.active = True def deactivate_plugin(self, plugin): # remove GUI extension points handlers (provided by plug-in) from # handlers list for gui_extpoint_name, gui_extpoint_handlers in \ plugin.gui_extension_points.items(): self.gui_extension_points_handlers[gui_extpoint_name].remove( gui_extpoint_handlers) # detaching plug-in from handler GUI extension points (calling # cleaning up method that must be provided by plug-in developer # for each handled GUI extension point) for gui_extpoint_name, gui_extpoint_handlers in \ plugin.gui_extension_points.items(): if gui_extpoint_name in self.gui_extension_points: for gui_extension_point_args in self.gui_extension_points[ gui_extpoint_name]: handler = gui_extpoint_handlers[1] if handler: try: handler(*gui_extension_point_args) except Exception as e: log.warning('Error executing %s', handler, exc_info=True) self._remove_events_handler_from_ged(plugin) self._remove_network_events_from_nec(plugin) self._remove_name_from_encryption_plugins(plugin) # removing plug-in from active plug-ins list plugin.deactivate() self.active_plugins.remove(plugin) self._set_plugin_active_in_global_config(plugin, False) plugin.active = False def _deactivate_all_plugins(self): for plugin_object in self.active_plugins: self.deactivate_plugin(plugin_object) @log_calls('PluginManager') def _add_gui_extension_points_handlers_from_plugin(self, plugin): for gui_extpoint_name, gui_extpoint_handlers in \ plugin.gui_extension_points.items(): self.gui_extension_points_handlers.setdefault(gui_extpoint_name, []).append(gui_extpoint_handlers) def _add_encryption_name_from_plugin(self, plugin): if plugin.encryption_name: self.encryption_plugins[plugin.encryption_name] = plugin @log_calls('PluginManager') def _handle_all_gui_extension_points_with_plugin(self, plugin): for gui_extpoint_name, gui_extpoint_handlers in \ plugin.gui_extension_points.items(): if gui_extpoint_name in self.gui_extension_points: for gui_extension_point_args in self.gui_extension_points[ gui_extpoint_name]: handler = gui_extpoint_handlers[0] if handler: try: handler(*gui_extension_point_args) except Exception as e: log.warning('Error executing %s', handler, exc_info=True) @log_calls('PluginManager') def _activate_all_plugins(self): ''' Activates all plugins in `plugins`. Activated plugins are appended to `active_plugins` list. ''' for plugin in self.plugins: try: self.activate_plugin(plugin) except GajimPluginActivateException: pass def _activate_all_plugins_from_global_config(self): for plugin in self.plugins: if self._plugin_is_active_in_global_config(plugin) and \ plugin.activatable: try: self.activate_plugin(plugin) except GajimPluginActivateException: pass def _plugin_is_active_in_global_config(self, plugin): return gajim.config.get_per('plugins', plugin.short_name, 'active') def _set_plugin_active_in_global_config(self, plugin, active=True): gajim.config.set_per('plugins', plugin.short_name, 'active', active) @staticmethod @log_calls('PluginManager') def scan_dir_for_plugins(path, scan_dirs=True, package=False): r''' Scans given directory for plugin classes. :param path: directory to scan for plugins :type path: str :param scan_dirs: folders inside path are processed as modules :type scan_dirs: boolean :param package: if path points to a single package folder :type package: boolean :return: list of found plugin classes (subclasses of `GajimPlugin` :rtype: [] of class objects :note: currently it only searches for plugin classes in '\*.py' files present in given direcotory `path` (no recursion here) :todo: add scanning zipped modules ''' from plugins.plugins_i18n import _ plugins_found = [] conf = configparser.ConfigParser() fields = ('name', 'short_name', 'version', 'description', 'authors', 'homepage') if not os.path.isdir(path): return plugins_found if package: path, package_name = os.path.split(path) dir_list = [package_name] else: dir_list = os.listdir(path) sys.path.insert(0, path) for elem_name in dir_list: file_path = os.path.join(path, elem_name) if os.path.isfile(file_path) and fnmatch.fnmatch(file_path, '*.py'): module_name = os.path.splitext(elem_name)[0] elif os.path.isdir(file_path) and scan_dirs: module_name = elem_name file_path += os.path.sep else: continue manifest_path = os.path.join(os.path.dirname(file_path), 'manifest.ini') if scan_dirs and (not os.path.isfile(manifest_path)): continue # read metadata from manifest.ini conf.remove_section('info') with open(manifest_path, encoding='utf-8') as conf_file: try: conf.read_file(conf_file) except configparser.Error: log.warning(("Plugin {plugin} not loaded, error loading" " manifest").format(plugin=elem_name) , exc_info=True) continue min_v = conf.get('info', 'min_gajim_version', fallback=None) max_v = conf.get('info', 'max_gajim_version', fallback=None) gajim_v = gajim.config.get('version').split('-', 1)[0] gajim_v_cmp = parse_version(gajim_v) if min_v and gajim_v_cmp < parse_version(min_v): log.warning(('Plugin {plugin} not loaded, newer version of' 'gajim required: {gajim_v} < {min_v}').format( plugin=elem_name, gajim_v=gajim_v, min_v=min_v )) continue if max_v and gajim_v_cmp > parse_version(max_v): log.warning(('Plugin {plugin} not loaded, plugin incompatible ' 'with current version of gajim: ' '{gajim_v} > {max_v}').format( plugin=elem_name, gajim_v=gajim_v, max_v=max_v )) continue module = None try: if module_name in sys.modules: if path == gajim.PLUGINS_DIRS[0]: # Only reload plugins from Gajim base dir when they # dont exist. This means plugins in the user path are # always preferred. continue from imp import reload log.info('Reloading %s', module_name) module = reload(sys.modules[module_name]) else: log.info('Loading %s', module_name) module = __import__(module_name) except Exception as error: log.warning( "While trying to load {plugin}, exception occurred".format(plugin=elem_name), exc_info=sys.exc_info() ) continue if module is None: continue log.debug('Attributes processing started') for module_attr_name in [attr_name for attr_name in dir(module) if not (attr_name.startswith('__') or attr_name.endswith('__'))]: module_attr = getattr(module, module_attr_name) log.debug('%s : %s' % (module_attr_name, module_attr)) try: if not issubclass(module_attr, GajimPlugin) or \ module_attr is GajimPlugin: continue log.debug('is subclass of GajimPlugin') module_attr.__path__ = os.path.abspath( os.path.dirname(file_path)) for option in fields: if conf.get('info', option) is '': raise configparser.NoOptionError('field empty') if option == 'description': setattr(module_attr, option, _(conf.get('info', option))) continue setattr(module_attr, option, conf.get('info', option)) plugins_found.append(module_attr) except TypeError: # set plugin localization try: module_attr._ = _ except AttributeError: pass except configparser.NoOptionError: # all fields are required log.debug('%s : %s' % (module_attr_name, 'wrong manifest file. all fields are required!')) except configparser.NoSectionError: # info section are required log.debug('%s : %s' % (module_attr_name, 'wrong manifest file. info section are required!')) except configparser.MissingSectionHeaderError: # info section are required log.debug('%s : %s' % (module_attr_name, 'wrong manifest file. section are required!')) sys.path.remove(path) return plugins_found def install_from_zip(self, zip_filename, owerwrite=None): ''' Install plugin from zip and return plugin ''' try: zip_file = zipfile.ZipFile(zip_filename) except zipfile.BadZipfile: # it is not zip file raise PluginsystemError(_('Archive corrupted')) except IOError: raise PluginsystemError(_('Archive empty')) if zip_file.testzip(): # CRC error raise PluginsystemError(_('Archive corrupted')) dirs = [] manifest = None for filename in zip_file.namelist(): if filename.startswith('.') or filename.startswith('/') or \ ('/' not in filename): # members not safe raise PluginsystemError(_('Archive is malformed')) if filename.endswith('/') and filename.find('/', 0, -1) < 0: dirs.append(filename.strip('/')) if 'manifest.ini' in filename.split('/')[1]: manifest = True if not manifest: return if len(dirs) > 1: raise PluginsystemError(_('Archive is malformed')) base_dir, user_dir = gajim.PLUGINS_DIRS plugin_dir = os.path.join(user_dir, dirs[0]) if os.path.isdir(plugin_dir): # Plugin dir already exists if not owerwrite: raise PluginsystemError(_('Plugin already exists')) self.remove_plugin(self.get_plugin_by_path(plugin_dir)) zip_file.extractall(user_dir) zip_file.close() plugins = self.scan_dir_for_plugins(plugin_dir, package=True) if not plugins: return self.add_plugin(plugins[0]) plugin = self.plugins[-1] return plugin def remove_plugin(self, plugin): ''' Deactivate and remove plugin from `plugins` list ''' def on_error(func, path, error): if func == os.path.islink: # if symlink os.unlink(path) return # access is denied or other raise PluginsystemError(error[1][1]) if plugin: if plugin.active: self.deactivate_plugin(plugin) rmtree(plugin.__path__, False, on_error) self.plugins.remove(plugin) if self._plugin_has_entry_in_global_config(plugin): self._remove_plugin_entry_in_global_config(plugin) del sys.modules[plugin.__module__.split('.')[0]] del plugin.__module__.split('.')[-1] del plugin def get_plugin_by_path(self, plugin_dir): for plugin in self.plugins: if plugin.__path__ in plugin_dir: return plugin