"""本模块实现插件加载流程。 参考: [import hooks](https://docs.python.org/3/reference/import.html#import-hooks), [PEP302](https://www.python.org/dev/peps/pep-0302/) FrontMatter: sidebar_position: 5 description: nonebot.plugin.manager 模块 """ import sys import pkgutil import importlib from pathlib import Path from itertools import chain from typing import Optional from types import ModuleType from importlib.abc import MetaPathFinder from collections.abc import Iterable, Sequence from importlib.machinery import PathFinder, SourceFileLoader from nonebot.log import logger from nonebot.utils import escape_tag, path_to_module_name from .model import Plugin, PluginMetadata from . import ( _managers, _new_plugin, _revert_plugin, _current_plugin, _module_name_to_plugin_id, ) class PluginManager: """插件管理器。 参数: plugins: 独立插件模块名集合。 search_path: 插件搜索路径（文件夹），相对于当前工作目录。 """ def __init__( self, plugins: Optional[Iterable[str]] = None, search_path: Optional[Iterable[str]] = None, ): # simple plugin not in search path self.plugins: set[str] = set(plugins or []) self.search_path: set[str] = set(search_path or []) # cache plugins self._third_party_plugin_ids: dict[str, str] = {} self._searched_plugin_ids: dict[str, str] = {} self._prepare_plugins() def __repr__(self) -> str: return f"PluginManager(available_plugins={self.controlled_modules})" @property def third_party_plugins(self) -> set[str]: """返回所有独立插件标识符。""" return set(self._third_party_plugin_ids.keys()) @property def searched_plugins(self) -> set[str]: """返回已搜索到的插件标识符。""" return set(self._searched_plugin_ids.keys()) @property def available_plugins(self) -> set[str]: """返回当前插件管理器中可用的插件标识符。""" return self.third_party_plugins | self.searched_plugins @property def controlled_modules(self) -> dict[str, str]: """返回当前插件管理器中控制的插件标识符与模块路径映射字典。""" return dict( chain( self._third_party_plugin_ids.items(), self._searched_plugin_ids.items() ) ) def _previous_controlled_modules(self) -> dict[str, str]: _pre_managers: list[PluginManager] if self in _managers: _pre_managers = _managers[: _managers.index(self)] else: _pre_managers = _managers[:] return { plugin_id: module_name for manager in _pre_managers for plugin_id, module_name in manager.controlled_modules.items() } def _prepare_plugins(self) -> set[str]: """搜索插件并缓存插件名称。""" # get all previous ready to load plugins previous_plugin_ids = self._previous_controlled_modules() # if self not in global managers, merge self's controlled modules def get_controlled_modules(): return ( previous_plugin_ids if self in _managers else {**previous_plugin_ids, **self.controlled_modules} ) # check third party plugins for plugin in self.plugins: plugin_id = _module_name_to_plugin_id(plugin, get_controlled_modules()) if ( plugin_id in self._third_party_plugin_ids or plugin_id in previous_plugin_ids ): raise RuntimeError( f"Plugin already exists: {plugin_id}! Check your plugin name" ) self._third_party_plugin_ids[plugin_id] = plugin # check plugins in search path for module_info in pkgutil.iter_modules(self.search_path): # ignore if startswith "_" if module_info.name.startswith("_"): continue if not ( module_spec := module_info.module_finder.find_spec( module_info.name, None ) ): continue if not module_spec.origin: continue # get module name from path, pkgutil does not return the actual module name module_path = Path(module_spec.origin).resolve() module_name = path_to_module_name(module_path) plugin_id = _module_name_to_plugin_id(module_name, get_controlled_modules()) if ( plugin_id in previous_plugin_ids or plugin_id in self._third_party_plugin_ids or plugin_id in self._searched_plugin_ids ): raise RuntimeError( f"Plugin already exists: {plugin_id}! Check your plugin name" ) self._searched_plugin_ids[plugin_id] = module_name return self.available_plugins def load_plugin(self, name: str) -> Optional[Plugin]: """加载指定插件。 可以使用完整插件模块名或者插件标识符加载。 参数: name: 插件名称或插件标识符。 """ try: # load using plugin id if name in self._third_party_plugin_ids: module = importlib.import_module(self._third_party_plugin_ids[name]) elif name in self._searched_plugin_ids: module = importlib.import_module(self._searched_plugin_ids[name]) # load using module name elif ( name in self._third_party_plugin_ids.values() or name in self._searched_plugin_ids.values() ): module = importlib.import_module(name) else: raise RuntimeError(f"Plugin not found: {name}! Check your plugin name") if ( plugin := getattr(module, "__plugin__", None) ) is None or not isinstance(plugin, Plugin): raise RuntimeError( f"Module {module.__name__} is not loaded as a plugin! " f"Make sure not to import it before loading." ) logger.opt(colors=True).success( f'Succeeded to load plugin "{escape_tag(plugin.id_)}"' + ( f' from "{escape_tag(plugin.module_name)}"' if plugin.module_name != plugin.id_ else "" ) ) return plugin except Exception as e: logger.opt(colors=True, exception=e).error( f'Failed to import "{escape_tag(name)}"' ) def load_all_plugins(self) -> set[Plugin]: """加载所有可用插件。""" return set( filter(None, (self.load_plugin(name) for name in self.available_plugins)) ) class PluginFinder(MetaPathFinder): def find_spec( self, fullname: str, path: Optional[Sequence[str]], target: Optional[ModuleType] = None, ): if _managers: module_spec = PathFinder.find_spec(fullname, path, target) if not module_spec: return module_origin = module_spec.origin if not module_origin: return for manager in reversed(_managers): if fullname in manager.controlled_modules.values(): module_spec.loader = PluginLoader(manager, fullname, module_origin) return module_spec return class PluginLoader(SourceFileLoader): def __init__(self, manager: PluginManager, fullname: str, path: str) -> None: self.manager = manager self.loaded = False super().__init__(fullname, path) def create_module(self, spec) -> Optional[ModuleType]: if self.name in sys.modules: self.loaded = True return sys.modules[self.name] # return None to use default module creation return super().create_module(spec) def exec_module(self, module: ModuleType) -> None: if self.loaded: return # create plugin before executing plugin = _new_plugin(self.name, module, self.manager) setattr(module, "__plugin__", plugin) # enter plugin context _plugin_token = _current_plugin.set(plugin) try: super().exec_module(module) except Exception: _revert_plugin(plugin) raise finally: # leave plugin context _current_plugin.reset(_plugin_token) # get plugin metadata metadata: Optional[PluginMetadata] = getattr(module, "__plugin_meta__", None) plugin.metadata = metadata return sys.meta_path.insert(0, PluginFinder())