Realtime

Ephemeral fanout for subscribers connected right now. → Realtime concept

Studio

Realtime → Listen on a channel, then Publish an event with a JSON payload; the log shows time #id channel event payload. Stop closes the stream.

hcloud

hcloud realtime listen  prj_… orders                     # prints events until Ctrl-C
hcloud realtime publish prj_… orders created '{"order": 42}'

curl

curl -N "$ORIGIN/v0/projects/$PRJ/realtime/sse?channel=orders&channel=system" \
  -H "Authorization: Bearer $TOKEN" -H 'Accept: text/event-stream'
curl -X POST $ORIGIN/v0/projects/$PRJ/realtime/publish -H "Authorization: Bearer $TOKEN" \
  -H 'Content-Type: application/json' -d '{"channel":"orders","event":"created","payload":{"order":42}}'

Reconnect with Last-Event-ID: <id> to receive the best-effort replay (last 64 events per channel).

JavaScript

const stop = cloud.realtime.subscribe(project.id, ["orders", "system"], (e) => console.log(e.id, e.channel, e.event, e.payload), {
  onEnd: (reason) => console.log("stream ended:", reason),
});
await cloud.realtime.publish(project.id, { channel: "orders", event: "created", payload: { order: 42 } });
stop();

Limits: 32 KiB payloads, 16 channels per connection, 32 connections per credential, streams end after 300 s without an event. Publishing to system is refused.