Events - API Reference

EventBusOptions

Options for new Event({ … }). Schema-first mode also accepts schema (nested Standard Schema map) for validation and InferEvents — that field lives on the conditional CreateEventConfig, not on EventBusOptions itself.

Option	Type	Description
`hooks?`	`object`	Lifecycle hooks for pipeline and error routing.
`onListenerError?`	`OnListenerErrorMode \| undefined`	How listener errors affect other listeners. Default: `"continue"`
`strategy?`	`object`	Listener execution strategy. Default: `parallelStrategy`
`stream?`	`object`	Cross-instance persistence and fan-out backend.
`verbose?`	`boolean \| VerboseLogger \| undefined`	Log pipeline steps to the console when `true`, or pass a duck-typed `{ info, warn, error }` adapter for custom routing. Silent by default. Default: `false`

EventBusHooks

Option	Type	Description
`onError?`	`ErrorHandler`	Initial `onError` handler (listener errors).
`onPipelineEnd?`	`function`	After middleware + listeners complete.
`onPipelineFinally?`	`function`	After pipeline attempt (success or failure). Skipped on validation failure.
`onPipelineStart?`	`function`	After validation, before middleware + listeners.
`onValidationError?`	`ErrorHandler`	Initial `onValidationError` handler.

EventBus

Typed async-first event bus returned by new Event({ … }). See Server for emit/dispatch and SSE wiring, Listeners for on / once / subscribe, and Namespaces for namespace and channel scoping.

ChannelEmitter

Channel-scoped emitter from event.channel(...names) — same emit API with channels merged into metadata. See Channel for client subscribe and Server for emit.

EventHandlerOptions

Options for handler({ … }).

Option	Type	Description
`authorizeJoin?`	`AuthorizeJoin`	Gate SSE channel join/leave before the connection is accepted.
`event`	`object`	Event bus instance to subscribe and replay from.
`maxDurationSecs?`	`number`	Max SSE connection duration in seconds before the server closes it.
`middleware?`	`HandlerMiddleware`	Run before subscribe; return a Response to reject the request.

OnOptions

Options for on / once.

Option	Type	Description
`priority?`	`number`	Higher runs first among listeners for the same event. Default: `0`
`signal?`	`object`	Abort to unregister the listener when the signal fires.

SubscribeEventOptions

Options-object form of server event.subscribe / channel.subscribe (channel-scoped form omits channels).

Option	Type	Description
`signal?`	`object`	Abort to unsubscribe when the signal fires.
`channels?`	`array`	Channel names to scope delivery; omit for bus-wide subscribe.
`events`	`K`	Event names to listen for.
`once?`	`boolean \| undefined`	Unsubscribe after the first matching delivery.
`onData`	`function`	Called for each matching event payload.
`priority?`	`number`	Higher runs first when multiple subscribers match.

MemoryStreamOptions

Option	Type	Description
`maxLength?`	`number`	Max messages retained per channel. Default: `100`

RedisStreamOptions

Option	Type	Description
`channelPrefix?`	`string`	Key/channel prefix. Default: `"@g14o:events"`
`client`	`RedisStreamClient`	Redis client (node-redis or ioredis).
`expireAfterSecs?`	`number`	Optional TTL applied to stream keys after append.
`maxLength?`	`number`	Max stream length (MAXLEN ≈).

UpstashStreamOptions

Option	Type	Description
`channelPrefix?`	`string`	Key/channel prefix. Default: `"@g14o:events"`
`expireAfterSecs?`	`number`	Optional TTL applied to stream keys after append.
`maxLength?`	`number`	Max stream length (MAXLEN).
`redis`	`object`	Upstash Redis REST client (or compatible).

EventStream

Pluggable stream contract for custom backends (defineStream). See Streams for built-in adapters and Deployment for multi-instance wiring.

EventProviderProps

Option	Type	Description
`api?`	`object`	SSE endpoint and fetch credentials.
`children`	`ReactNode`
`maxReconnectAttempts?`	`number`	Max automatic reconnect attempts after disconnect.

ProviderApiConfig

Option	Type	Description
`url?`	`string`	SSE subscribe URL (default `/api/events`).
`withCredentials?`	`boolean \| undefined`	Send cookies on the EventSource request.

UseEventOptions

Client hook options from createEvent().useEvent. The channels option scopes delivery — see Channel.

Option	Type	Description
`channels?`	`array`	Channel names to subscribe to (undefined entries are ignored).
`enabled?`	`boolean \| undefined`	When false, skip registering until enabled.
`events?`	`array`	Event names to receive; omit for all typed events.
`onData?`	`function`	Called for each matching realtime message.

PipelineLogOptions

Options for createPipelineLog.

Option	Type	Description
`formatEnd?`	`function`	Format a pipeline-end log line.
`formatStart?`	`function`	Format a pipeline-start log line.
`maxEntries?`	`number`	Max middleware log entries retained in memory.

Package entry points

Import	Description
`@g14o/events`	`Event`, `handler`, strategies, errors, `createPipelineLog`, `defineStream`
`@g14o/events/client`	`EventProvider`, `createEvent`, hooks
`@g14o/events/memory`	`memoryStream`
`@g14o/events/redis`	`redisStream`
`@g14o/events/upstash`	`upstashStream`

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