Demo 9 — Admin Web UI

Module brief: §Module 9

UVP

A working dashboard at http://<proxy>:9090/ — single embedded HTML file, no build step, ten panels covering every v0.4.0 capability.

Use cases

On-call. Open the dashboard, see “current primary” + “healthy nodes” + “active anomalies” in one view. No Grafana to set up.
Post-incident review. The Anomalies panel + Replay panel together let you see what happened and replay traffic from before the incident against a copy of the DB.
Ad-hoc investigation. SQL panel sends queries through the proxy’s load-balancer; useful for sanity checks without a separate psql session.

What this demo shows

cd demos/v0.4.0/09-admin-ui
./demo.sh

The script brings up the proxy + PG, then opens the dashboard in your browser (or prints the URL if no browser is detected):

=== Admin UI Demo ===
[1/2] Starting proxy + Postgres
[2/2] Dashboard at http://localhost:9090/

   Open in your browser. The page auto-refreshes every 5 seconds
   so you can leave it open while exercising the proxy elsewhere.

Panels you’ll see

Nodes — health, failure count, latency, last check
Topology — current primary, healthy/unhealthy counts, last failover (red badge when no primary is healthy)
Plugins — name, version, hooks, state, invocation count, error count (red when > 0)
Anomalies — recent detections from the anomaly module
Edge Mode — cache stats, registered edges, manual invalidate
Chaos Mode — force-unhealthy buttons + active overrides
Shadow Execution — diff a query across two backends
Time-Travel Replay — replay a journal window
SQL Console — ad-hoc query box
Traffic / Cluster — counters (queries, bytes, sessions)

Try this once the dashboard is open:

# Generate some load — the Traffic panel should tick up
for i in $(seq 1 200); do
  PGPASSWORD=postgres psql -h localhost -p 6432 -U postgres -d demo \
    -c "SELECT 1" >/dev/null 2>&1 &
done
wait

Refresh the dashboard — Queries processed should jump to ~200, Active sessions will spike then settle.

Implementation pointer

src/admin_ui.html — the whole dashboard, ~1 200 lines of vanilla HTML/CSS/JS. Served by src/admin.rs::handle_connection at GET / and GET /ui via include_str!.

HeliosDB compatibility

Backend-agnostic.