⚗️ add export require option

nonebot/plugin.py

@@ -11,6 +11,7 @@ import pkgutil
 import importlib
 from dataclasses import dataclass
 from importlib._bootstrap import _load
+from contextvars import Context, ContextVar, copy_context
 
 from nonebot.log import logger
 from nonebot.matcher import Matcher
@@ -25,7 +26,45 @@ plugins: Dict[str, "Plugin"] = {}
 :说明: 已加载的插件
 """
 
-_tmp_matchers: Set[Type[Matcher]] = set()
+_tmp_matchers: ContextVar[Set[Type[Matcher]]] = ContextVar("_tmp_matchers")
+_export: ContextVar["Export"] = ContextVar("_export")
+
+
+class Export(dict):
+    """
+    :说明:
+      插件导出内容以使得其他插件可以获得。
+    :示例:
+
+    .. code-block:: python
+
+        nonebot.export().default = "bar"
+
+        @nonebot.export()
+        def some_function():
+            pass
+
+        @nonebot.export().sub
+        def something_else():
+            pass
+    """
+
+    def __call__(self, func, **kwargs):
+        self[func.__name__] = func
+        self.update(kwargs)
+        return func
+
+    def __setitem__(self, key, value):
+        super().__setitem__(key,
+                            Export(value) if isinstance(value, dict) else value)
+
+    def __setattr__(self, name, value):
+        self[name] = Export(value) if isinstance(value, dict) else value
+
+    def __getattr__(self, name):
+        if name not in self:
+            self[name] = Export()
+        return self[name]
 
 
 @dataclass(eq=False)
@@ -46,6 +85,7 @@ class Plugin(object):
     - **类型**: ``Set[Type[Matcher]]``
     - **说明**: 插件内定义的 ``Matcher``
     """
+    export: Export
 
 
 def on(type: str = "",
@@ -80,7 +120,7 @@ def on(type: str = "",
                           block=block,
                           handlers=handlers,
                           default_state=state)
-    _tmp_matchers.add(matcher)
+    _tmp_matchers.get().add(matcher)
     return matcher
 
 
@@ -112,7 +152,7 @@ def on_metaevent(rule: Optional[Union[Rule, RuleChecker]] = None,
                           block=block,
                           handlers=handlers,
                           default_state=state)
-    _tmp_matchers.add(matcher)
+    _tmp_matchers.get().add(matcher)
     return matcher
 
 
@@ -146,7 +186,7 @@ def on_message(rule: Optional[Union[Rule, RuleChecker]] = None,
                           block=block,
                           handlers=handlers,
                           default_state=state)
-    _tmp_matchers.add(matcher)
+    _tmp_matchers.get().add(matcher)
     return matcher
 
 
@@ -178,7 +218,7 @@ def on_notice(rule: Optional[Union[Rule, RuleChecker]] = None,
                           block=block,
                           handlers=handlers,
                           default_state=state)
-    _tmp_matchers.add(matcher)
+    _tmp_matchers.get().add(matcher)
     return matcher
 
 
@@ -210,7 +250,7 @@ def on_request(rule: Optional[Union[Rule, RuleChecker]] = None,
                           block=block,
                           handlers=handlers,
                           default_state=state)
-    _tmp_matchers.add(matcher)
+    _tmp_matchers.get().add(matcher)
     return matcher
 
 
@@ -387,27 +427,35 @@ def load_plugin(module_path: str) -> Optional[Plugin]:
     :返回:
       - ``Optional[Plugin]``
     """
-    try:
-        _tmp_matchers.clear()
-        if module_path in plugins:
-            return plugins[module_path]
-        elif module_path in sys.modules:
-            logger.warning(
-                f"Module {module_path} has been loaded by other plugins! Ignored"
+
+    def _load_plugin(module_path: str) -> Optional[Plugin]:
+        try:
+            _tmp_matchers.set(set())
+            _export.set(Export())
+            if module_path in plugins:
+                return plugins[module_path]
+            elif module_path in sys.modules:
+                logger.warning(
+                    f"Module {module_path} has been loaded by other plugins! Ignored"
+                )
+                return
+            module = importlib.import_module(module_path)
+            for m in _tmp_matchers.get():
+                m.module = module_path
+            plugin = Plugin(module_path, module, _tmp_matchers.get(),
+                            _export.get())
+            plugins[module_path] = plugin
+            logger.opt(
+                colors=True).info(f'Succeeded to import "<y>{module_path}</y>"')
+            return plugin
+        except Exception as e:
+            logger.opt(colors=True, exception=e).error(
+                f'<r><bg #f8bbd0>Failed to import "{module_path}"</bg #f8bbd0></r>'
             )
-            return
-        module = importlib.import_module(module_path)
-        for m in _tmp_matchers:
-            m.module = module_path
-        plugin = Plugin(module_path, module, _tmp_matchers.copy())
-        plugins[module_path] = plugin
-        logger.opt(
-            colors=True).info(f'Succeeded to import "<y>{module_path}</y>"')
-        return plugin
-    except Exception as e:
-        logger.opt(colors=True, exception=e).error(
-            f'<r><bg #f8bbd0>Failed to import "{module_path}"</bg #f8bbd0></r>')
-        return None
+            return None
+
+    context: Context = copy_context()
+    return context.run(_load_plugin, module_path)
 
 
 def load_plugins(*plugin_dir: str) -> Set[Plugin]:
@@ -419,33 +467,42 @@ def load_plugins(*plugin_dir: str) -> Set[Plugin]:
     :返回:
       - ``Set[Plugin]``
     """
-    loaded_plugins = set()
-    for module_info in pkgutil.iter_modules(plugin_dir):
-        _tmp_matchers.clear()
+
+    def _load_plugin(module_info) -> Optional[Plugin]:
+        _tmp_matchers.set(set())
+        _export.set(Export())
         name = module_info.name
         if name.startswith("_"):
-            continue
+            return
 
         spec = module_info.module_finder.find_spec(name, None)
         if spec.name in plugins:
-            continue
+            return
         elif spec.name in sys.modules:
             logger.warning(
                 f"Module {spec.name} has been loaded by other plugin! Ignored")
-            continue
+            return
 
         try:
             module = _load(spec)
 
-            for m in _tmp_matchers:
+            for m in _tmp_matchers.get():
                 m.module = name
-            plugin = Plugin(name, module, _tmp_matchers.copy())
+            plugin = Plugin(name, module, _tmp_matchers.get(), _export.get())
             plugins[name] = plugin
-            loaded_plugins.add(plugin)
             logger.opt(colors=True).info(f'Succeeded to import "<y>{name}</y>"')
+            return plugin
         except Exception as e:
             logger.opt(colors=True, exception=e).error(
                 f'<r><bg #f8bbd0>Failed to import "{name}"</bg #f8bbd0></r>')
+            return None
+
+    loaded_plugins = set()
+    for module_info in pkgutil.iter_modules(plugin_dir):
+        context: Context = copy_context()
+        result = context.run(_load_plugin, module_info)
+        if result:
+            loaded_plugins.add(result)
     return loaded_plugins
 
 
@@ -479,3 +536,12 @@ def get_loaded_plugins() -> Set[Plugin]:
       - ``Set[Plugin]``
     """
     return set(plugins.values())
+
+
+def export() -> Export:
+    return _export.get()
+
+
+def require(name: str) -> Optional[Export]:
+    plugin = get_plugin(name)
+    return plugin.export if plugin else None