Node-RED: Lecture 3 – Example 3.3 Using a change node to change or manipulate a message payload

Another useful node is the change node, which will allow you to change a message payload or add new properties. You can use this node to affect the properties in a message, either by changing existing ones, deleting them or adding new properties.

In this example, you’ll continue with your MQTT theme and see how, now that you have successfully ‘switched’ the message flow based on the incoming MQTT message, you can add a new message property msg.payload.note.… Read the rest

Node-RED: Lecture 3 – Example 3.2 Using the switch node to handle a JSON object

This example continues to use the MQTT node we setup in Example 3.1. If you aren’t following these examples sequentially you may want to review example 3.1 as it shows how to use the free MQTT broker, HiveMQ which is needed for the MQTT node.

One of the nice features of having a JSON object is that you can easily act on its properties.… Read the rest