EventResult

Each handler execution for an event produces one EventResult. You usually access results through event.event_results (or high-level event helper methods), but this page documents the underlying object.

Common fields

id: unique result id
status: pending | started | completed | error
result: handler return value (typed by event result schema/type)
error: captured exception/error when handler fails
started_at, completed_at (None/null until the handler starts/completes)
event_children: child events emitted from inside this handler execution
Handler metadata (handler_id, handler_name, handler_file_path, bus label/id/name)

Await semantics

Awaiting an EventResult resolves to handler return value or raises captured failure in Python. TypeScript and Go expose the stored result/error fields directly; Go’s Wait(...) only waits for settlement.

Python
TypeScript
Go
Rust

entry = event.event_results[some_handler_id]
value = await entry

const [, entry] = Array.from(event.event_results.entries())[0]
const value = entry.result

for _, entry := range event.EventResults {
	if err := entry.Wait(); err != nil {
		return err
	}
	value := entry.Result
	_ = value
	break
}

let entry = event
    .event_results
    .read()
    .values()
    .next()
    .cloned()
    .expect("handler result");
let value = entry.result.clone();

Lifecycle

Every handler entry follows the same public lifecycle in each runtime:

pending: the event has accepted the handler result slot, but the handler has not started.
started: the handler callable is running.
completed: the handler returned a valid value or None / null / nil.
error: the handler raised, returned an invalid value, timed out, or was cancelled/aborted by completion policy.

Use event.event_results for the per-handler mapping and event_result() / eventResult() / EventResult() / event_result().await when you only need the first typed raw result value.

Serialization

Python
TypeScript
Go
Rust

payload = entry.model_dump(mode='json')
print(payload)
# {
#   "id": "0190...",
#   "status": "completed",
#   "event_id": "018f...",
#   "handler_id": "018g...",
#   "handler_name": "on_user_created",
#   "result": {"user_id": "u_123"},
#   "error": None,
#   "...": "..."
# }

restored = EventResult.model_validate(payload)

const payload = entry.toJSON()
console.log(payload)
// {
//   id: '0190...',
//   status: 'completed',
//   event_id: '018f...',
//   handler: { id: '018g...', handler_name: 'onUserCreated', ... },
//   result: { user_id: 'u_123' },
//   error: undefined,
//   ...
// }

const restored = EventResult.fromJSON(event, payload)

payload, err := json.Marshal(entry)
fmt.Println(string(payload))
// {
//   "id": "0190...",
//   "status": "completed",
//   "event_id": "018f...",
//   "handler_id": "018g...",
//   "handler_name": "on_user_created",
//   "result": {"user_id": "u_123"},
//   "error": null,
//   ...
// }

restored, err := abxbus.EventResultFromJSON(payload)

let payload = serde_json::to_value(&entry)?;
println!("{}", serde_json::to_string_pretty(&payload)?);
// {
//   "id": "0190...",
//   "status": "completed",
//   "event_id": "018f...",
//   "handler_id": "018g...",
//   "handler_name": "on_user_created",
//   "result": {"user_id": "u_123"},
//   "error": null,
//   ...
// }

let restored: abxbus::event_result::EventResult = serde_json::from_value(payload)?;

Getting Started

Features

API Reference

Concurrency Control

Integrations

Further Reading

Common fields

Await semantics

Lifecycle

Serialization

​Common fields

​Await semantics

​Lifecycle

​Serialization

Common fields

Await semantics

Lifecycle

Serialization