Live tail
Live tail is a mode of the Messages tab, not a separate screen. The toolbar carries a two-way switch: History shows stored messages, Realtime opens a live subscription and streams messages in as they arrive.
Payloads decode on the fly. When you change a .proto source while a live session runs, Natscope re-decodes with the new schema without a reconnect. See Protobuf.
Start a tail
- Open a stream and go to the Messages tab.
- Switch the toolbar toggle to Realtime.
- Optional: open Filters and set a Subject pattern to narrow the feed. NATS wildcards work.
Messages arrive in batches with live throughput stats: messages per second, per-subject counts and dropped-message tracking.
Control the flow
Realtime mode adds three controls to the toolbar:
- Pause / Resume: stop and restart intake without dropping the subscription
- Clear: empty the live buffer
- Display rate: No limit, 1 msg/s, 5 msg/s, 10 msg/s, 25 msg/s or 50 msg/s
The rate limit throttles what the UI renders. It does not slow the stream or the subscription. A busy work queue at 1 msg/s stays readable while the server keeps running at full speed.
A separate dropdown caps how many live messages the buffer holds. Older ones fall off the top.
A browser tab in the background lets go of its live subscriptions, Realtime, Subscribe and KV live updates alike, and picks them up again when you come back; messages that arrive meanwhile are not shown. A browser keeps only six connections open to one address, so this is what lets many natscope tabs stay usable.
Subscription mode
Settings → Preferences → Live picks how the tail subscribes:
- Core NATS: a plain subject subscription
- JetStream Ordered: an ordered ephemeral consumer bound to the stream
The same section sets Max display rate as a default, so new tails start throttled. Under Display, Default view mode decides whether a stream opens in History or Realtime, and Auto-scroll live keeps the list pinned to the newest message.