# coding=utf-8 """ In this module resides the core data structures and logic of the plugin system. It is implemented in an OctoPrint-agnostic way and could be extracted into a separate Python module in the future. .. autoclass:: PluginManager :members: .. autoclass:: PluginInfo :members: .. autoclass:: Plugin :members: """ from __future__ import absolute_import __author__ = "Gina Häußge " __license__ = 'GNU Affero General Public License http://www.gnu.org/licenses/agpl.html' __copyright__ = "Copyright (C) 2014 The OctoPrint Project - Released under terms of the AGPLv3 License" import os import imp from collections import defaultdict, namedtuple import logging import pkg_resources import pkginfo EntryPointOrigin = namedtuple("EntryPointOrigin", "type, entry_point, module_name, package_name, package_version") FolderOrigin = namedtuple("FolderOrigin", "type, folder") class PluginInfo(object): """ The :class:`PluginInfo` class wraps all available information about a registered plugin. This includes its meta data (like name, description, version, etc) as well as the actual plugin extensions like implementations, hooks and helpers. It works on Python module objects and extracts the relevant data from those via accessing the :ref:`control properties `. Arguments: key (str): Identifier of the plugin location (str): Installation folder of the plugin instance (module): Plugin module instance name (str): Human readable name of the plugin version (str): Version of the plugin description (str): Description of the plugin author (str): Author of the plugin url (str): URL of the website of the plugin license (str): License of the plugin """ attr_name = '__plugin_name__' """ Module attribute from which to retrieve the plugin's human readable name. """ attr_description = '__plugin_description__' """ Module attribute from which to retrieve the plugin's description. """ attr_version = '__plugin_version__' """ Module attribute from which to retrieve the plugin's version. """ attr_author = '__plugin_author__' """ Module attribute from which to retrieve the plugin's author. """ attr_url = '__plugin_url__' """ Module attribute from which to retrieve the plugin's website URL. """ attr_license = '__plugin_license__' """ Module attribute from which to retrieve the plugin's license. """ attr_hooks = '__plugin_hooks__' """ Module attribute from which to retrieve the plugin's provided hooks. """ attr_implementation = '__plugin_implementation__' """ Module attribute from which to retrieve the plugin's provided mixin implementation. """ attr_implementations = '__plugin_implementations__' """ Module attribute from which to retrieve the plugin's provided implementations. This deprecated attribute will only be used if a plugin does not yet offer :attr:`attr_implementation`. Only the first entry will be evaluated. .. deprecated:: 1.2.0-dev-694 Use :attr:`attr_implementation` instead. """ attr_helpers = '__plugin_helpers__' """ Module attribute from which to retrieve the plugin's provided helpers. """ attr_check = '__plugin_check__' """ Module attribute which to call to determine if the plugin can be loaded. """ attr_init = '__plugin_init__' """ Module attribute which to call when loading the plugin. This deprecated attribute will only be used if a plugin does not yet offer :attr:`attr_load`. .. deprecated:: 1.2.0-dev-720 Use :attr:`attr_load` instead. """ attr_load = '__plugin_load__' """ Module attribute which to call when loading the plugin. """ attr_unload = '__plugin_unload__' """ Module attribute which to call when unloading the plugin. """ attr_enable = '__plugin_enable__' """ Module attribute which to call when enabling the plugin. """ attr_disable = '__plugin_disable__' """ Module attribute which to call when disabling the plugin. """ def __init__(self, key, location, instance, name=None, version=None, description=None, author=None, url=None, license=None): self.key = key self.location = location self.instance = instance self.origin = None self.enabled = True self.bundled = False self.loaded = False self._name = name self._version = version self._description = description self._author = author self._url = url self._license = license def validate(self): # if the plugin still uses __plugin_implementations__, log a deprecation warning and put the first # item into __plugin_implementation__ if hasattr(self.instance, self.__class__.attr_implementations): if not hasattr(self.instance, self.__class__.attr_implementation): # deprecation warning import warnings warnings.warn("{name} uses deprecated control property __plugin_implementations__, use __plugin_implementation__ instead - only the first implementation of {name} will be recognized".format(name=self.key), DeprecationWarning) # put first item into __plugin_implementation__ implementations = getattr(self.instance, self.__class__.attr_implementations) if len(implementations) > 0: setattr(self.instance, self.__class__.attr_implementation, implementations[0]) # delete __plugin_implementations__ delattr(self.instance, self.__class__.attr_implementations) # if the plugin still uses __plugin_init__, log a deprecation warning and move it to __plugin_load__ if hasattr(self.instance, self.__class__.attr_init): if not hasattr(self.instance, self.__class__.attr_load): # deprecation warning import warnings warnings.warn("{name} uses deprecated control property __plugin_init__, use __plugin_load__ instead".format(name=self.key), DeprecationWarning) # move it init = getattr(self.instance, self.__class__.attr_init) setattr(self.instance, self.__class__.attr_load, init) # delete __plugin_init__ delattr(self.instance, self.__class__.attr_init) def __str__(self): if self.version: return "{name} ({version})".format(name=self.name, version=self.version) else: return self.name def long_str(self, show_bundled=False, bundled_strs=(" [B]", ""), show_location=False, location_str=" - {location}", show_enabled=False, enabled_strs=("* ", " ")): """ Long string representation of the plugin's information. Will return a string of the format ````. ``enabled``, ``bundled`` and ``location`` will only be displayed if the corresponding flags are set to ``True``. The will be filled from ``enabled_str``, ``bundled_str`` and ``location_str`` as follows: ``enabled_str`` a 2-tuple, the first entry being the string to insert when the plugin is enabled, the second entry the string to insert when it is not. ``bundled_str`` a 2-tuple, the first entry being the string to insert when the plugin is bundled, the second entry the string to insert when it is not. ``location_str`` a format string (to be parsed with ``str.format``), the ``{location}`` placeholder will be replaced with the plugin's installation folder on disk. Arguments: show_enabled (boolean): whether to show the ``enabled`` part enabled_strs (tuple): the 2-tuple containing the two possible strings to use for displaying the enabled state show_bundled (boolean): whether to show the ``bundled`` part bundled_strs(tuple): the 2-tuple containing the two possible strings to use for displaying the bundled state show_location (boolean): whether to show the ``location`` part location_str (str): the format string to use for displaying the plugin's installation location Returns: str: The long string representation of the plugin as described above """ if show_enabled: ret = enabled_strs[0] if self.enabled else enabled_strs[1] else: ret = "" ret += str(self) if show_bundled: ret += bundled_strs[0] if self.bundled else bundled_strs[1] if show_location and self.location: ret += location_str.format(location=self.location) return ret def get_hook(self, hook): """ Arguments: hook (str): Hook to return. Returns: callable or None: Handler for the requested ``hook`` or None if no handler is registered. """ if not hook in self.hooks: return None return self.hooks[hook] def get_implementation(self, *types): """ Arguments: types (list): List of :class:`Plugin` sub classes all returned implementations need to implement. Returns: object: The plugin's implementation if it matches all of the requested ``types``, None otherwise. """ if not self.implementation: return None for t in types: if not isinstance(self.implementation, t): return None return self.implementation @property def name(self): """ Human readable name of the plugin. Will be taken from name attribute of the plugin module if available, otherwise from the ``name`` supplied during construction with a fallback to ``key``. Returns: str: Name of the plugin, fallback is the plugin's identifier. """ return self._get_instance_attribute(self.__class__.attr_name, defaults=(self._name, self.key)) @property def description(self): """ Description of the plugin. Will be taken from the description attribute of the plugin module as defined in :attr:`attr_description` if available, otherwise from the ``description`` supplied during construction. May be None. Returns: str or None: Description of the plugin. """ return self._get_instance_attribute(self.__class__.attr_description, default=self._description) @property def version(self): """ Version of the plugin. Will be taken from the version attribute of the plugin module as defined in :attr:`attr_version` if available, otherwise from the ``version`` supplied during construction. May be None. Returns: str or None: Version of the plugin. """ return self._version if self._version is not None else self._get_instance_attribute(self.__class__.attr_version, default=self._version) @property def author(self): """ Author of the plugin. Will be taken from the author attribute of the plugin module as defined in :attr:`attr_author` if available, otherwise from the ``author`` supplied during construction. May be None. Returns: str or None: Author of the plugin. """ return self._get_instance_attribute(self.__class__.attr_author, default=self._author) @property def url(self): """ Website URL for the plugin. Will be taken from the url attribute of the plugin module as defined in :attr:`attr_url` if available, otherwise from the ``url`` supplied during construction. May be None. Returns: str or None: Website URL for the plugin. """ return self._get_instance_attribute(self.__class__.attr_url, default=self._url) @property def license(self): """ License of the plugin. Will be taken from the license attribute of the plugin module as defined in :attr:`attr_license` if available, otherwise from the ``license`` supplied during construction. May be None. Returns: str or None: License of the plugin. """ return self._get_instance_attribute(self.__class__.attr_license, default=self._license) @property def hooks(self): """ Hooks provided by the plugin. Will be taken from the hooks attribute of the plugin module as defiend in :attr:`attr_hooks` if available, otherwise an empty dictionary is returned. Returns: dict: Hooks provided by the plugin. """ return self._get_instance_attribute(self.__class__.attr_hooks, default={}) @property def implementation(self): """ Implementation provided by the plugin. Will be taken from the implementation attribute of the plugin module as defined in :attr:`attr_implementation` if available, otherwise None is returned. Returns: object: Implementation provided by the plugin. """ return self._get_instance_attribute(self.__class__.attr_implementation, default=None) @property def helpers(self): """ Helpers provided by the plugin. Will be taken from the helpers attribute of the plugin module as defined in :attr:`attr_helpers` if available, otherwise an empty list is returned. Returns: dict: Helpers provided by the plugin. """ return self._get_instance_attribute(self.__class__.attr_helpers, default={}) @property def check(self): """ Method for pre-load check of plugin. Will be taken from the check attribute of the plugin module as defined in :attr:`attr_check` if available, otherwise a lambda always returning True is returned. Returns: callable: Check method for the plugin module which should return True if the plugin can be loaded, False otherwise. """ return self._get_instance_attribute(self.__class__.attr_check, default=lambda: True) @property def load(self): """ Method for loading the plugin module. Will be taken from the load attribute of the plugin module as defined in :attr:`attr_load` if available, otherwise a no-operation lambda will be returned. Returns: callable: Load method for the plugin module. """ return self._get_instance_attribute(self.__class__.attr_load, default=lambda: True) @property def unload(self): """ Method for unloading the plugin module. Will be taken from the unload attribute of the plugin module as defined in :attr:`attr_unload` if available, otherwise a no-operation lambda will be returned. Returns: callable: Unload method for the plugin module. """ return self._get_instance_attribute(self.__class__.attr_unload, default=lambda: True) @property def enable(self): """ Method for enabling the plugin module. Will be taken from the enable attribute of the plugin module as defined in :attr:`attr_enable` if available, otherwise a no-operation lambda will be returned. Returns: callable: Enable method for the plugin module. """ return self._get_instance_attribute(self.__class__.attr_enable, default=lambda: True) @property def disable(self): """ Method for disabling the plugin module. Will be taken from the disable attribute of the plugin module as defined in :attr:`attr_disable` if available, otherwise a no-operation lambda will be returned. Returns: callable: Disable method for the plugin module. """ return self._get_instance_attribute(self.__class__.attr_disable, default=lambda: True) def _get_instance_attribute(self, attr, default=None, defaults=None): if not hasattr(self.instance, attr): if defaults is not None: for value in defaults: if value is not None: return value return default return getattr(self.instance, attr) class PluginManager(object): """ The :class:`PluginManager` is the central component for finding, loading and accessing plugins provided to the system. It is able to discover plugins both through possible file system locations as well as customizable entry points. """ def __init__(self, plugin_folders, plugin_types, plugin_entry_points, logging_prefix=None, plugin_disabled_list=None, plugin_restart_needing_hooks=None, plugin_obsolete_hooks=None): self.logger = logging.getLogger(__name__) if logging_prefix is None: logging_prefix = "" if plugin_disabled_list is None: plugin_disabled_list = [] self.plugin_folders = plugin_folders self.plugin_types = plugin_types self.plugin_entry_points = plugin_entry_points self.plugin_disabled_list = plugin_disabled_list self.plugin_restart_needing_hooks = plugin_restart_needing_hooks self.plugin_obsolete_hooks = plugin_obsolete_hooks self.logging_prefix = logging_prefix self.enabled_plugins = dict() self.disabled_plugins = dict() self.plugin_hooks = defaultdict(list) self.plugin_implementations = dict() self.plugin_implementations_by_type = defaultdict(list) self.implementation_injects = dict() self.implementation_inject_factories = [] self.on_plugin_loaded = lambda *args, **kwargs: None self.on_plugin_unloaded = lambda *args, **kwargs: None self.on_plugin_enabled = lambda *args, **kwargs: None self.on_plugin_disabled = lambda *args, **kwargs: None self.on_plugin_implementations_initialized = lambda *args, **kwargs: None self.registered_clients = [] self.marked_plugins = defaultdict(list) self.reload_plugins(startup=True, initialize_implementations=False) @property def plugins(self): plugins = dict(self.enabled_plugins) plugins.update(self.disabled_plugins) return plugins def find_plugins(self, existing=None, ignore_uninstalled=True): if existing is None: existing = self.plugins result = dict() if self.plugin_folders: result.update(self._find_plugins_from_folders(self.plugin_folders, existing, ignored_uninstalled=ignore_uninstalled)) if self.plugin_entry_points: result.update(self._find_plugins_from_entry_points(self.plugin_entry_points, existing, ignore_uninstalled=ignore_uninstalled)) return result def _find_plugins_from_folders(self, folders, existing, ignored_uninstalled=True): result = dict() for folder in folders: readonly = False if isinstance(folder, (list, tuple)): if len(folder) == 2: folder, readonly = folder else: continue if not os.path.exists(folder): self.logger.warn("Plugin folder {folder} could not be found, skipping it".format(folder=folder)) continue entries = os.listdir(folder) for entry in entries: path = os.path.join(folder, entry) if os.path.isdir(path) and os.path.isfile(os.path.join(path, "__init__.py")): key = entry elif os.path.isfile(path) and entry.endswith(".py"): key = entry[:-3] # strip off the .py extension else: continue if key in existing or key in result or (ignored_uninstalled and key in self.marked_plugins["uninstalled"]): # plugin is already defined, ignore it continue plugin = self._import_plugin_from_module(key, folder=folder) if plugin: plugin.origin = FolderOrigin("folder", folder) if readonly: plugin.bundled = True plugin.enabled = False result[key] = plugin return result def _find_plugins_from_entry_points(self, groups, existing, ignore_uninstalled=True): result = dict() # let's make sure we have a current working set working_set = pkg_resources.WorkingSet() if not isinstance(groups, (list, tuple)): groups = [groups] for group in groups: for entry_point in working_set.iter_entry_points(group=group, name=None): key = entry_point.name module_name = entry_point.module_name version = entry_point.dist.version if key in existing or key in result or (ignore_uninstalled and key in self.marked_plugins["uninstalled"]): # plugin is already defined or marked as uninstalled, ignore it continue kwargs = dict(module_name=module_name, version=version) package_name = None try: module_pkginfo = InstalledEntryPoint(entry_point) except: self.logger.exception("Something went wrong while retrieving package info data for module %s" % module_name) else: kwargs.update(dict( name=module_pkginfo.name, summary=module_pkginfo.summary, author=module_pkginfo.author, url=module_pkginfo.home_page, license=module_pkginfo.license )) package_name = module_pkginfo.name plugin = self._import_plugin_from_module(key, **kwargs) if plugin: plugin.origin = EntryPointOrigin("entry_point", group, module_name, package_name, version) plugin.enabled = False result[key] = plugin return result def _import_plugin_from_module(self, key, folder=None, module_name=None, name=None, version=None, summary=None, author=None, url=None, license=None): # TODO error handling try: if folder: module = imp.find_module(key, [folder]) elif module_name: module = imp.find_module(module_name) else: return None except: self.logger.warn("Could not locate plugin {key}") return None plugin = self._import_plugin(key, *module, name=name, version=version, summary=summary, author=author, url=url, license=license) if plugin is None: return None if plugin.check(): return plugin else: self.logger.warn("Plugin \"{plugin}\" did not pass check".format(plugin=str(plugin))) return None def _import_plugin(self, key, f, filename, description, name=None, version=None, summary=None, author=None, url=None, license=None): try: instance = imp.load_module(key, f, filename, description) return PluginInfo(key, filename, instance, name=name, version=version, description=summary, author=author, url=url, license=license) except: self.logger.exception("Error loading plugin {key}".format(key=key)) return None def _is_plugin_disabled(self, key): return key in self.plugin_disabled_list or key.endswith('disabled') def reload_plugins(self, startup=False, initialize_implementations=True, force_reload=None): self.logger.info("Loading plugins from {folders} and installed plugin packages...".format( folders=", ".join(map(lambda x: x[0] if isinstance(x, tuple) else str(x), self.plugin_folders)) )) if force_reload is None: force_reload = [] plugins = self.find_plugins(existing=dict((k, v) for k, v in self.plugins.items() if not k in force_reload)) self.disabled_plugins.update(plugins) for name, plugin in plugins.items(): try: self.load_plugin(name, plugin, startup=startup, initialize_implementation=initialize_implementations) if not self._is_plugin_disabled(name): self.enable_plugin(name, plugin=plugin, initialize_implementation=initialize_implementations, startup=startup) except PluginNeedsRestart: pass except PluginLifecycleException as e: self.logger.info(str(e)) if len(self.enabled_plugins) <= 0: self.logger.info("No plugins found") else: self.logger.info("Found {count} plugin(s) providing {implementations} mixin implementations, {hooks} hook handlers".format( count=len(self.enabled_plugins) + len(self.disabled_plugins), implementations=len(self.plugin_implementations), hooks=sum(map(lambda x: len(x), self.plugin_hooks.values())) )) def mark_plugin(self, name, uninstalled=None): if not name in self.plugins: self.logger.warn("Trying to mark an unknown plugin {name}".format(**locals())) if uninstalled is not None: if uninstalled and not name in self.marked_plugins["uninstalled"]: self.marked_plugins["uninstalled"].append(name) elif not uninstalled and name in self.marked_plugins["uninstalled"]: self.marked_plugins["uninstalled"].remove(name) def load_plugin(self, name, plugin=None, startup=False, initialize_implementation=True): if not name in self.plugins: self.logger.warn("Trying to load an unknown plugin {name}".format(**locals())) return if plugin is None: plugin = self.plugins[name] try: plugin.load() plugin.validate() self.on_plugin_loaded(name, plugin) plugin.loaded = True self.logger.debug("Loaded plugin {name}: {plugin}".format(**locals())) except PluginLifecycleException as e: raise e except: self.logger.exception("There was an error loading plugin %s" % name) def unload_plugin(self, name): if not name in self.plugins: self.logger.warn("Trying to unload unknown plugin {name}".format(**locals())) return plugin = self.plugins[name] try: if plugin.enabled: self.disable_plugin(name, plugin=plugin) plugin.unload() self.on_plugin_unloaded(name, plugin) if name in self.enabled_plugins: del self.enabled_plugins[name] if name in self.disabled_plugins: del self.disabled_plugins[name] plugin.loaded = False self.logger.debug("Unloaded plugin {name}: {plugin}".format(**locals())) except PluginLifecycleException as e: raise e except: self.logger.exception("There was an error unloading plugin {name}".format(**locals())) # make sure the plugin is NOT in the list of enabled plugins but in the list of disabled plugins if name in self.enabled_plugins: del self.enabled_plugins[name] if not name in self.disabled_plugins: self.disabled_plugins[name] = plugin def enable_plugin(self, name, plugin=None, initialize_implementation=True, startup=False): if not name in self.disabled_plugins: self.logger.warn("Tried to enable plugin {name}, however it is not disabled".format(**locals())) return if plugin is None: plugin = self.disabled_plugins[name] if not startup and self.is_restart_needing_plugin(plugin): raise PluginNeedsRestart(name) if self.has_obsolete_hooks(plugin): raise PluginCantEnable(name, "Dependency on obsolete hooks detected, full functionality cannot be guaranteed") try: plugin.enable() self._activate_plugin(name, plugin) except PluginLifecycleException as e: raise e except: self.logger.exception("There was an error while enabling plugin {name}".format(**locals())) return False else: if name in self.disabled_plugins: del self.disabled_plugins[name] self.enabled_plugins[name] = plugin plugin.enabled = True if plugin.implementation: if initialize_implementation: if not self.initialize_implementation_of_plugin(name, plugin): return False plugin.implementation.on_plugin_enabled() self.on_plugin_enabled(name, plugin) self.logger.debug("Enabled plugin {name}: {plugin}".format(**locals())) return True def disable_plugin(self, name, plugin=None): if not name in self.enabled_plugins: self.logger.warn("Tried to disable plugin {name}, however it is not enabled".format(**locals())) return if plugin is None: plugin = self.enabled_plugins[name] if self.is_restart_needing_plugin(plugin): raise PluginNeedsRestart(name) try: plugin.disable() self._deactivate_plugin(name, plugin) except PluginLifecycleException as e: raise e except: self.logger.exception("There was an error while disabling plugin {name}".format(**locals())) return False else: if name in self.enabled_plugins: del self.enabled_plugins[name] self.disabled_plugins[name] = plugin plugin.enabled = False if plugin.implementation: plugin.implementation.on_plugin_disabled() self.on_plugin_disabled(name, plugin) self.logger.debug("Disabled plugin {name}: {plugin}".format(**locals())) return True def _activate_plugin(self, name, plugin): plugin.hotchangeable = self.is_restart_needing_plugin(plugin) # evaluate registered hooks for hook, callback in plugin.hooks.items(): self.plugin_hooks[hook].append((name, callback)) # evaluate registered implementation if plugin.implementation: for plugin_type in self.plugin_types: if isinstance(plugin.implementation, plugin_type): self.plugin_implementations_by_type[plugin_type].append((name, plugin.implementation)) self.plugin_implementations[name] = plugin.implementation def _deactivate_plugin(self, name, plugin): for hook, callback in plugin.hooks.items(): try: self.plugin_hooks[hook].remove((name, callback)) except ValueError: # that's ok, the plugin was just not registered for the hook pass if plugin.implementation is not None: if name in self.plugin_implementations: del self.plugin_implementations[name] for plugin_type in self.plugin_types: try: self.plugin_implementations_by_type[plugin_type].remove((name, plugin.implementation)) except ValueError: # that's ok, the plugin was just not registered for the type pass def is_restart_needing_plugin(self, plugin): return self.has_restart_needing_implementation(plugin) or self.has_restart_needing_hooks(plugin) def has_restart_needing_implementation(self, plugin): if not plugin.implementation: return False return isinstance(plugin.implementation, RestartNeedingPlugin) def has_restart_needing_hooks(self, plugin): if not plugin.hooks: return False hooks = plugin.hooks.keys() for hook in hooks: if self.is_restart_needing_hook(hook): return True return False def has_obsolete_hooks(self, plugin): if not plugin.hooks: return False hooks = plugin.hooks.keys() for hook in hooks: if self.is_obsolete_hook(hook): return True return False def is_restart_needing_hook(self, hook): if self.plugin_restart_needing_hooks is None: return False for h in self.plugin_restart_needing_hooks: if hook.startswith(h): return True return False def is_obsolete_hook(self, hook): if self.plugin_obsolete_hooks is None: return False return hook in self.plugin_obsolete_hooks def initialize_implementations(self, additional_injects=None, additional_inject_factories=None): for name, plugin in self.enabled_plugins.items(): self.initialize_implementation_of_plugin(name, plugin, additional_injects=additional_injects, additional_inject_factories=additional_inject_factories) self.logger.info("Initialized {count} plugin(s)".format(count=len(self.plugin_implementations))) def initialize_implementation_of_plugin(self, name, plugin, additional_injects=None, additional_inject_factories=None): if plugin.implementation is None: return return self.initialize_implementation(name, plugin, plugin.implementation, additional_injects=additional_injects, additional_inject_factories=additional_inject_factories) def initialize_implementation(self, name, plugin, implementation, additional_injects=None, additional_inject_factories=None): if additional_injects is None: additional_injects = dict() if additional_inject_factories is None: additional_inject_factories = [] injects = self.implementation_injects injects.update(additional_injects) inject_factories = self.implementation_inject_factories inject_factories += additional_inject_factories try: kwargs = dict(injects) kwargs.update(dict( identifier=name, plugin_name=plugin.name, plugin_version=plugin.version, basefolder=os.path.realpath(plugin.location), logger=logging.getLogger(self.logging_prefix + name), )) # inject the additional_injects for arg, value in kwargs.items(): setattr(implementation, "_" + arg, value) # inject any injects produced in the additional_inject_factories for factory in inject_factories: try: return_value = factory(name, implementation) except: self.logger.exception("Exception while executing injection factory %r" % factory) else: if return_value is not None: if isinstance(return_value, dict): for arg, value in return_value.items(): setattr(implementation, "_" + arg, value) implementation.initialize() except Exception as e: self._deactivate_plugin(name, plugin) plugin.enabled = False if isinstance(e, PluginLifecycleException): raise e else: self.logger.exception("Exception while initializing plugin {name}, disabling it".format(**locals())) return False else: self.on_plugin_implementations_initialized(name, plugin) self.logger.debug("Initialized plugin mixin implementation for plugin {name}".format(**locals())) return True def log_all_plugins(self, show_bundled=True, bundled_str=(" (bundled)", ""), show_location=True, location_str=" = {location}", show_enabled=True, enabled_str=(" ", "!")): all_plugins = self.enabled_plugins.values() + self.disabled_plugins.values() if len(all_plugins) <= 0: self.logger.info("No plugins available") else: self.logger.info("{count} plugin(s) registered with the system:\n{plugins}".format(count=len(all_plugins), plugins="\n".join( sorted( map(lambda x: "| " + x.long_str(show_bundled=show_bundled, bundled_strs=bundled_str, show_location=show_location, location_str=location_str, show_enabled=show_enabled, enabled_strs=enabled_str), self.enabled_plugins.values()) ) ))) def get_plugin(self, identifier, require_enabled=True): """ Retrieves the module of the plugin identified by ``identifier``. If the plugin is not registered or disabled and ``required_enabled`` is True (the default) None will be returned. Arguments: identifier (str): The identifier of the plugin to retrieve. require_enabled (boolean): Whether to only return the plugin if is enabled (True, default) or also if it's disabled. Returns: module: The requested plugin module or None """ plugin_info = self.get_plugin_info(identifier, require_enabled=require_enabled) if plugin_info is not None: return plugin_info.instance return None def get_plugin_info(self, identifier, require_enabled=True): """ Retrieves the :class:`PluginInfo` instance identified by ``identifier``. If the plugin is not registered or disabled and ``required_enabled`` is True (the default) None will be returned. Arguments: identifier (str): The identifier of the plugin to retrieve. require_enabled (boolean): Whether to only return the plugin if is enabled (True, default) or also if it's disabled. Returns: ~.PluginInfo: The requested :class:`PluginInfo` or None """ if identifier in self.enabled_plugins: return self.enabled_plugins[identifier] elif not require_enabled and identifier in self.disabled_plugins: return self.disabled_plugins[identifier] return None def get_hooks(self, hook): """ Retrieves all registered handlers for the specified hook. Arguments: hook (str): The hook for which to retrieve the handlers. Returns: dict: A dict containing all registered handlers mapped by their plugin's identifier. """ if not hook in self.plugin_hooks: return dict() return {hook[0]: hook[1] for hook in self.plugin_hooks[hook]} def get_implementations(self, *types): """ Get all mixin implementations that implement *all* of the provided ``types``. Arguments: types (one or more type): The types a mixin implementation needs to implement in order to be returned. Returns: list: A list of all found implementations """ result = None for t in types: implementations = self.plugin_implementations_by_type[t] if result is None: result = set(implementations) else: result = result.intersection(implementations) if result is None: return dict() return [impl[1] for impl in result] def get_filtered_implementations(self, f, *types): """ Get all mixin implementation that implementat *all* of the provided ``types`` and match the provided filter `f`. Arguments: f (callable): A filter function returning True for implementations to return and False for those to exclude. types (one or more type): The types a mixin implementation needs to implement in order to be returned. Returns: list: A list of all found and matching implementations. """ assert callable(f) implementations = self.get_implementations(*types) return filter(f, implementations) def get_helpers(self, name, *helpers): """ Retrieves the named ``helpers`` for the plugin with identifier ``name``. If the plugin is not available, returns None. Otherwise returns a :class:`dict` with the requested plugin helper names mapped to the method - if a helper could not be resolved, it will be missing from the dict. Arguments: name (str): Identifier of the plugin for which to look up the ``helpers``. helpers (one or more str): Identifiers of the helpers of plugin ``name`` to return. Returns: dict: A dictionary of all resolved helpers, mapped by their identifiers, or None if the plugin was not registered with the system. """ if not name in self.enabled_plugins: return None plugin = self.enabled_plugins[name] all_helpers = plugin.helpers if len(helpers): return dict((k, v) for (k, v) in all_helpers.items() if k in helpers) else: return all_helpers def register_message_receiver(self, client): """ Registers a ``client`` for receiving plugin messages. The ``client`` needs to be a callable accepting two input arguments, ``plugin`` (the sending plugin's identifier) and ``data`` (the message itself). """ if client is None: return self.registered_clients.append(client) def unregister_message_receiver(self, client): """ Unregisters a ``client`` for receiving plugin messages. """ self.registered_clients.remove(client) def send_plugin_message(self, plugin, data): """ Sends ``data`` in the name of ``plugin`` to all currently registered message receivers by invoking them with the two arguments. Arguments: plugin (str): The sending plugin's identifier. data (object): The message. """ for client in self.registered_clients: try: client(plugin, data) except: self.logger.exception("Exception while sending plugin data to client") class InstalledEntryPoint(pkginfo.Installed): def __init__(self, entry_point, metadata_version=None): self.entry_point = entry_point package = entry_point.module_name pkginfo.Installed.__init__(self, package, metadata_version=metadata_version) def read(self): import sys import glob import warnings opj = os.path.join if self.package is not None: package = self.package.__package__ if package is None: package = self.package.__name__ project = pkg_resources.to_filename(pkg_resources.safe_name(self.entry_point.dist.project_name)) package_pattern = '%s*.egg-info' % package project_pattern = '%s*.egg-info' % project file = getattr(self.package, '__file__', None) if file is not None: candidates = [] def _add_candidate(where): candidates.extend(glob.glob(where)) for entry in sys.path: if file.startswith(entry): _add_candidate(opj(entry, 'EGG-INFO')) # egg? for pattern in (package_pattern, project_pattern): # dist-installed? _add_candidate(opj(entry, pattern)) dir, name = os.path.split(self.package.__file__) for pattern in (package_pattern, project_pattern): _add_candidate(opj(dir, pattern)) _add_candidate(opj(dir, '..', pattern)) for candidate in candidates: if os.path.isdir(candidate): path = opj(candidate, 'PKG-INFO') else: path = candidate if os.path.exists(path): with open(path) as f: return f.read() warnings.warn('No PKG-INFO found for package: %s' % self.package_name) class Plugin(object): """ The parent class of all plugin implementations. .. attribute:: _identifier The identifier of the plugin. Injected by the plugin core system upon initialization of the implementation. .. attribute:: _plugin_name The name of the plugin. Injected by the plugin core system upon initialization of the implementation. .. attribute:: _plugin_version The version of the plugin. Injected by the plugin core system upon initialization of the implementation. .. attribute:: _basefolder The base folder of the plugin. Injected by the plugin core system upon initialization of the implementation. .. attribute:: _logger The logger instance to use, with the logging name set to the :attr:`PluginManager.logging_prefix` of the :class:`PluginManager` concatenated with :attr:`_identifier`. Injected by the plugin core system upon initialization of the implementation. """ def initialize(self): """ Called by the plugin core after performing all injections. Override this to initialize your implementation. """ pass def on_plugin_enabled(self): pass def on_plugin_disabled(self): pass class RestartNeedingPlugin(Plugin): pass class PluginNeedsRestart(BaseException): def __init__(self, name): super(BaseException, self).__init__() self.name = name self.message = "Plugin {name} cannot be enabled or disabled after system startup".format(**locals()) class PluginLifecycleException(BaseException): def __init__(self, name, reason, message): super(BaseException, self).__init__() self.name = name self.reason = reason self.message = message.format(**locals()) def __str__(self): return self.message class PluginCantInitialize(PluginLifecycleException): def __init__(self, name, reason): super(PluginLifecycleException, self).__init__(name, reason, "Plugin {name} cannot be initialized: {reason}") class PluginCantEnable(PluginLifecycleException): def __init__(self, name, reason): PluginLifecycleException.__init__(self, name, reason, "Plugin {name} cannot be enabled: {reason}") class PluginCantDisable(PluginLifecycleException): def __init__(self, name, reason): super(PluginLifecycleException, self).__init__(name, reason, "Plugin {name} cannot be disabled: {reason}")