eventbus

type Callback ¶

type Callback func(event Event, err error)

Callback is a callback function that is called when an event is processed by the listener.

type Event ¶

type Event interface {
	// ID returns the ID of the event.
	ID() ids.ID
	// Name returns the name of the event.
	Name() EventName
}

type EventBus ¶

type EventBus interface {
	Start() error
	Stop() error
	// Publish publishes an event. Methods can return before the Event is handled.
	Publish(event Event, options ...Option) error

	// Subscribe subscribes to an event.
	// The handler will be called when the event is published.
	// The handler can return an error, which will be returned by the Publish method.
	Subscribe(eventName EventName, handler EventHandler) error
}

EventBus allows to publish and subscribe to events. It is a simple interface that allows to decouple the event publishing from the event handling. The handler can return an error, which will be returned by the Publish method. The publisher can publish as fire-and-forget, or wait for the handler to confirm the processing (replyHandler).

type EventEnvelope ¶

type EventEnvelope struct {
	Event      Event
	Err        error
	Ctx        context.Context
	Callback   Callback
	ShouldWait bool
}

EventEnvelope is a wrapper around the event that is sent to the bus. It holds other information that is used by the bus to process the event.

func (e *EventEnvelope) ProcessOptions(options []Option)

type EventHandler ¶

type EventHandler func(event Event) error

type EventName ¶

type EventName = string

type Option ¶

type Option func(*EventEnvelope)

func WithAck(callback Callback) Option

func WithWait() Option