Node-RED Local Flow Dashboard
Build a local flow that validates simulated telemetry and displays it without exposing the editor publicly.
Topology and objective
MQTT/input node → JSON validation → chart/gauge → command output.
Hardware and tools
- Supported development board
- USB data cable
- Current-limited supply
- Serial monitor and logic analyser when applicable
Security and RF safety
- Protect the editor with authentication.nDo not expose port 1880 directly to the internet.nStore broker secrets in credentials, not exported flow JSON.
Practical procedure
- Run Node-RED on a trusted local machine.nImport a minimal lab flow.nValidate topic and JSON schema.nDisplay a chart and online status.nInject an allowlisted command and verify acknowledgement.
Telemetry / payload
[{"id":"input","type":"mqtt in","topic":"tcs/lab/+/telemetry"}]Starter code / config
Flow: input → JSON → validate → chart; command button → allowlist → MQTT out.Expected results
| Checkpoint | Expected | Tool |
|---|---|---|
| Flow | Valid message reaches chart | Node-RED debugnInvalid JSON |
Troubleshooting
| Symptom | Check | Action |
|---|---|---|
| Flow disconnected | Check broker/server status | Reconnect locallynNo chart |
Local-only sandbox
Commands & telemetry simulator
Send command
Simulator ready. No network connection is used.