How to trigger Python script on Raspberry Pi from Node-Red

python raspberry-pi gpio iot node-red
pronoob picture pronoob · Aug 17, 2015 · Viewed 21k times · Source

I'm using Node-Red, hosted on a Raspberry Pi for an IoT project.

How do I trigger a Python script that is on the raspi from Node-Red? I want to run a script that updates the text on an Adafruit LCD shield which is sitting on the Pi

Should I be looking to expose the Python script as a web service somehow?

I'm using a Raspberry Pi B+

Answer

hardillb picture hardillb · Aug 17, 2015

Node-RED supplies an exec node as part of it's core set, which can be used to call external commands, this could be call your python script.

More details of how to use it can be found in the info sidebar when a copy is dragged onto the canvas.

Or you could wrap the script as a web service or just a simple TCP socket, both of which have nodes that can be used to drive them.

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