Support for Server-Sent Events in Swift through AsyncSequence.
Hummingbird 2's ResponseBody is already conforming to AsyncSequence<ByteBuffer>, so you can use the APIs easily.
There's Example Code in this repository for Hummingbird 2.
import SSEKit
router.get("events") { req, context in
// Get any `AsyncSequence<ServerSentEvent>`. We'll use AsyncStream to make it easy
let (events, continuation) = AsyncStream<ServerSentEvent>.makeStream()
// TODO: Emit events into `continuation` using your logic
// This logic emits the current time as ISO8601
let now = ISO8601DateFormatter().string(from: Date())
continuation.yield(ServerSentEvent(data: SSEValue(string: now)))
// Closing the stream is important, as omitting this will let the body hang indefinitely
continuation.finish()
let body = ResponseBody(asyncSequence: events.mapToByteBuffer(allocator: context.allocator))
return Response(status: .ok, headers: [.contentType: "text/event-stream"], body: body)
}