EventGroup unstable

Defines groups of typed events for the unstable event-log system.

An EventGroup collects event definitions that belong together. Start with empty, add events with their payload, success, and error schemas, then use the group to build clients with EventLog.schema and server handlers with EventLog.group. The group only describes events; it does not write or run them.

11 exports Since v4.0.0 Source

Constructors

empty

unstable

Since v4.0.0

Creates an empty event group used as the starting point for defining a group.

When to use

Use when you need the starting EventGroup value before adding event definitions with .add(...).

Signature

declare const empty: EventGroup<never>

Guards

isEventGroup

unstable

Since v4.0.0

Returns true when a value is an event log event group.

Signature

declare function isEventGroup(u: unknown): u is Any

Models

Any

interface unstable

Since v4.0.0

Type-erased marker for an event log event group.

Signature

interface Any {
  readonly "~effect/eventlog/EventGroup": "~effect/eventlog/EventGroup";
}

AnyWithProps

type unstable

Since v4.0.0

Type-erased event group with its events record available structurally.

Signature

type AnyWithProps = EventGroup<Event.Any>

EventGroup

interface unstable

Since v4.0.0

Typed collection of event definitions that represents a portion of an event log domain.

When to use

Use when build groups from empty.add(...), then provide implementations for the events with EventLog.group.

Signature

interface EventGroup<out Events extends Event.Any = Event.Any> extends Pipeable {
  readonly "~effect/eventlog/EventGroup": "~effect/eventlog/EventGroup";
  readonly events: Record.ReadonlyRecord<string, Events>;
  add<Tag extends string, Payload extends Top = Void, Success extends Top = Void, Error extends Top = Never>(options: {
    readonly error?: Error;
    readonly payload?: Payload;
    readonly primaryKey: (payload: Type<Payload>) => string;
    readonly success?: Success;
    readonly tag: Tag;
  }): EventGroup<Events | Event<Tag, Payload, Success, Error>>;
  addError<Error extends Top>(error: Error): EventGroup<AddError<Events, Error>>;
}

Type IDs

TypeId

unstable

Since v4.0.0

Runtime type identifier used to mark event log event groups.

Signature

declare const TypeId: "~effect/eventlog/EventGroup"

TypeId

type unstable

Since v4.0.0

Unique type identifier used to mark event log event groups.

Signature

type TypeId = "~effect/eventlog/EventGroup"

Utility Types

Events

type unstable

Since v4.0.0

Extracts the union of event definitions contained in an event group.

Signature

type Events<Group> = Group extends EventGroup<infer _Events> ? _Events : never

ServicesClient

type unstable

Since v4.0.0

Client-side schema services required by all events in an event group.

Signature

type ServicesClient<Group> = Event.ServicesClient<Events<Group>>

ServicesServer

type unstable

Since v4.0.0

Server-side schema services required by all events in an event group.

Signature

type ServicesServer<Group> = Event.ServicesServer<Events<Group>>

ToService

type unstable

Since v4.0.0

Derives the handler service markers required for all events in an event group.

Signature

type ToService<A> = A extends EventGroup<infer _Events> ? Event.ToService<_Events> : never