TopicEventSource

Source: src/AWS/SNS/TopicEventSource.ts

Event source connecting an SNS Topic to the hosting Lambda function: it creates the lambda-protocol subscription (plus the invoke permission) at deploy time and dispatches delivered notifications to the registered handler at runtime.

The contract is a Binding.Service; the Lambda implementation layer is Lambda.TopicEventSource. Consume it through the consumeTopicNotifications helper.

Consuming a Topic

export default WorkerFunction.make(
  { main: import.meta.url },
  Effect.gen(function* () {
    const topic = yield* SNS.Topic("Events");

    // registers the subscription and the runtime dispatcher
    yield* SNS.consumeTopicNotifications(topic, (stream) =>
      stream.pipe(
        Stream.runForEach((message) => Effect.log(message.Message)),
      ),
    );
  }).pipe(Effect.provide(Lambda.TopicEventSource)),
);