sse

The sse function is a subset of the http namespace that helps you create request handlers to intercept Server-Sent Events.

Call signature

sse<EventMap, Params>(predicate: Path, resolver: ServerSentEventResolver<EventMap, Params>)

Resolver argument

In addition to all the arguments exposed by the http namespace, the sse handler has the following response resolver properties:

ServerSentEventClient

The ServerSentEventClient object represents the intercepted EventSource instance. You use this object to send mock messages to the client, close or error the underlying connection.

.send(payload)

• payload
  • id, string (Optional), a custom event ID.
  • data, string, the sent data of this event.
  • event, string (Optional), a custom event type.
  • retry, number (Optional), a custom reconnection time. If this option is provided, no other properties must be set on the payload argument.

Sends a mocked event to the client.

// Send a default "message" event.
client.send({ data: 'hello world' })
 
// Send a custom "greeting" event.
client.send({
	event: 'greeting'
  data: 'Hello, John!',
})
 
// Send an event with a custom ID.
client.send({
	id: 'abc-123',
	event: 'greeting'
  data: 'Hello, John!',
})

.error()

Errors the underlying HTTP connection.

client.error()

.close()

Gracefully closes the underlying HTTP connection.

client.close()

ServerSentEventServer

The ServerSentEventClient object represents a connection to the actual server. Use it to establish that connection and listen to the received events from the server.

.connect()

…TODO

const source = server.connect()

…TODO What is returned as source and what you can use it for (listen to messages, close the connection).

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