Module event_handler

Types and traits related for event handlers. For usage, see Client::add_event_handler.

How it works

The add_event_handler method registers event handlers of different signatures by actually storing boxed closures that all have the same signature of async (EventHandlerData) -> () where EventHandlerData is a private type that contains all of the data an event handler might need.

The stored closure takes care of deserializing the event which the EventHandlerData contains as a (borrowed) serde_json::value::RawValue, extracting the context arguments from other fields of EventHandlerData and calling / .awaiting the event handler if the previous steps succeeded. It also logs any errors from the above chain of function calls.

For more details, see the EventHandler trait.

Structs

• Ctx
  A custom value registered with .add_event_handler_context.
• EventHandlerDropGuard
  A guard type that removes an event handler when it drops (goes out of scope).
• EventHandlerHandle
  Handle to remove a registered event handler by passing it to Client::remove_event_handler.
• EventHandlerSubscriber
  The subscriber of an ObservableEventHandler.
• ObservableEventHandler
  An observer of events (may be tailored to a room).
• RawEvent
  The raw JSON form of an event.

Traits

• EventHandler
  Interface for event handlers.
• EventHandlerContext
  Context for an event handler.
• EventHandlerResult
  Return types supported for event handlers implement this trait.
• SyncEvent
  A statically-known event kind/type that can be retrieved from an event sync.