MQTT Explorer

/tools/mqtt-explorer connects directly to the Edge Server's embedded Sparkplug B broker over MQTT-over-WebSockets and gives you a live, browsable view of the topic tree.

Connection

Field	Default	Notes
Host	page origin	Defaults to the host the UI is loaded from.
Port	page port	Same as the UI port (typically 3041).
Path	/mqtt	The broker is co-hosted with the UI at /mqtt.

Click Connect to open the session; the status badge cycles through Connecting → Connected (or Error). Disconnect closes it.

Topic tree

The left panel shows a collapsible Sparkplug B hierarchy (group → edge node → device → metric). Each branch displays a message-count badge. Selecting a topic opens the detail view on the right.

Payload detail

• Latest message metadata (topic, timestamp, size).
• A decoded Sparkplug B metrics table with Name, Type, Value, and Timestamp.
• History picker for navigating older messages on the same topic (capped per topic to keep memory predictable).

Controls

• Pause — freezes incoming traffic. New messages are dropped while paused and a counter shows how many were missed.
• Clear — wipes the topic tree without disconnecting.
• Send Command — only enabled on Sparkplug B topics; opens the NCMD/DCMD composer.

Send Command dialog

• NCMD actions: Rebirth (force the edge node to republish its DBIRTH) and Reboot.
• DCMD writes to a specific metric: pick the metric (from the most recent DBIRTH), choose its datatype, and supply a value. Boolean metrics get a switch; numeric metrics get an input.
• The dialog shows the metric's current value and flashes when a new DDATA arrives, giving you immediate confirmation that your command landed.