Monnit Edge Flows — Node-RED Basics

Node-RED basics

Official docs (bookmark these):

Getting started: https://nodered.org/docs/getting-started/
Using the editor: https://nodered.org/docs/user-guide/editor/
Working with messages: https://nodered.org/docs/user-guide/messages
Full docs home: https://nodered.org/docs/

1. What Node-RED is

Node-RED is a flow editor. You connect boxes (nodes) with lines (wires).

Messages travel left → right along wires when the flow is Deployed.

A tab (top of the canvas: 00, 01, 02…) is one page of a flow.

2. Parts of the screen (every item)

Left — Palette

Lists every node type you can add (common, network, Monnit, …)
Search box at the top: type a name (e.g. debug , inject )
Drag a node onto the canvas to add it
Categories can be collapsed/expanded

Center — Canvas (workspace)

Where your flow lives
Pan: click empty space and drag, or use scrollbars
Zoom: browser zoom or editor zoom controls (if shown)
Select: click a node (it highlights)
Move: drag a selected node
Wire: drag from the small circle on the right of a node to the circle on the left of another
Delete wire: click the wire, press Delete
Delete node: select it, press Delete
Tabs along the top switch between flow pages

Top bar

menu (☰): Import / Export / Search flows / Settings / Keyboard shortcuts
Deploy (red button): applies your changes — nothing new runs until you Deploy
Deploy options (dropdown on the button): usually Full is fine for this lab

Icon / panel	What it is for
info	Help text for the selected node (read this when stuck)
help	Longer documentation for that node type
debug	Live messages from debug nodes (most important for testing)
config	Shared config nodes (brokers, BACnet networks, …)

If the sidebar is hidden, use the tabs/icons on the far right edge to open it.

3. Nodes, wires, and messages

Term	Meaning
Node	One step (inject, debug, BACnet, …)
Wire	Path a message takes between nodes
Message (`msg` )	A JavaScript object; almost always has `msg.payload`
`msg.topic`	Optional string label (often a sensor id)
Status	Text under a node after Deploy (green/yellow/red hints)
Config node	Shared settings opened via a pencil icon inside a node dialog

4. How to configure a node (every time)

Double-click the node on the canvas
A dialog opens with that node’s settings
Change fields (dropdowns, checkboxes, text)
Click Done (saves into the editor, not yet live)
Click Deploy (makes it live on the Edge)

Pencil icon next to a field (Network, Broker, …) opens a config node — ports, passwords, device IDs. Edit those carefully, then Update → Done → Deploy.

Cancel discards dialog changes. Delete in the dialog removes the node.

5. Deploy — why it matters

Edits on the canvas are drafts until Deploy
After Deploy, heartbeats start, listeners bind ports, MQTT connects
If something “does nothing,” you usually forgot Deploy
A successful Deploy shows a short confirmation; errors appear in notifications / log

6. Debug — how to see data (detail)

Add / use a debug node

Palette → common → debug (or use the one on this tab)
Wire any node’s output → debug input
Double-click the debug node:

Setting	What to choose
Output	`msg.payload` = only the payload; complete message object = everything (`payload` , `topic` , …)
to sidebar	checked — show in the Debug panel
to console	optional — also prints in the Node-RED log
Name	optional label so you know which debug fired

Done → Deploy

Open the Debug panel

Right sidebar → click the bug icon (debug)
New messages appear as they flow (newest at the bottom or top depending on version)
Click a message to expand objects/arrays
Use the Debug panel toolbar to:

- Clear old messages

- Filter (all nodes vs current flow) — if you see nothing, set filter to all or open the correct tab

- Pause/open as needed

What “good” looks like

After you click Click me below, Debug shows one string message
Later tabs: Debug shows sensor objects with sensorId / readings

Debug shows nothing?

Did you Deploy?
Is the debug node wired from something that actually sends?
Is to sidebar enabled on the debug node?
Is the Debug panel filter hiding this flow?
Is the upstream node stopped/error (red status)?

7. Practice

Click Deploy
Click the small square on the left of Click me (that button fires one message)
Open Debug on the right — read the text
Double-click Click me — change the payload text → Done → Deploy → click again
Double-click Debug sidebar — switch Output to complete message object → Done → Deploy → click inject again → expand the message in Debug

When that feels comfortable, open tab 02 Path.

8. Official help

More depth, screenshots, and keyboard shortcuts:

https://nodered.org/docs/getting-started/

https://nodered.org/docs/user-guide/editor/

https://nodered.org/docs/user-guide/messages