# 事件(Events) 订阅内核事件。**注意**:外部分布式插件的事件订阅不走 `Events()`(该接口在外部插件路径上未被注入,恒为 nil),而是由 `hmapdev` 生成的运行时通过 `events.subscribe` 完成。详见下方说明。 ## `EventSubscriber` EventSubscriber allows plugins to subscribe to kernel events. This is a restricted interface: plugins can subscribe but the kernel controls which events are delivered. | 方法 | 说明 | |---|---| | [`Subscribe`](#eventsubscribersubscribe) | | ### `EventSubscriber.Subscribe` !!! warning "仅内核内置插件可用" ```go Subscribe(eventType EventType, handler EventHandler) func() ``` `plugin.go:279` ### `Event` ```go type Event struct { Type EventType `json:"type"` Source string `json:"source"` Payload map[string]interface{} `json:"payload"` T … ``` Event represents a system event published by the kernel. `plugin.go:265` ### `EventHandler` ```go type EventHandler func(evt *Event) ``` EventHandler processes a system event. `plugin.go:273` ### `EventType` ```go type EventType string ``` EventType identifies the kind of system event. `plugin.go:247` ### `PluginSDK.Events` !!! warning "仅内核内置插件可用" 实测全仓 SetEventSubscriber 只有定义、无任何调用点(grep -rn SetEventSubscriber --include=*.go 仅命中 sdk/plugin.go 的定义与 lua_plugin.go 的一句注释)。外部插件拿到的 Events() 恒为 nil。外部插件订阅事件走的是桥接运行时的 events.subscribe RPC(proc_main.go.tmpl:1421 在插件侧分发、内核 protocol.go MethodEventsSubscribe),Lua 插件则走内部 SDK 的 Subscribe。这正是 PLUGIN_DEV.md 里没有说清的一处。 ```go func (s *PluginSDK) Events() EventSubscriber ``` Events returns the event subscriber for listening to kernel events (may be nil if not available). `plugin.go:446`