The server supports subscribing to SSE messages via HTTP GET to the URL path configured by the --sub-path=<path> option (defaults to /sse).
curl --include 127.0.0.1:1983/sse
HTTP/1.1 200 OK
content-type: text/event-stream
cache-control: no-cache
: ok
id: some-id
event: custom-event
data: Some data
: First comment
: Second comment
: keep-alive
Upon successful subscription, the server will immediately respond with the SSE comment ok indicating that the connection is established and waiting for new messages.
Keep-alive messages (SSE comments) are sent periodically to ensure the connection stays open and is not closed by intermediate proxies due to socket inactivity. These messages are configurable with the --keep-alive and --keep-alive-text options.