Node-red services.autretechlab.cloud

Le Monde de Sora Minecraft Roleplay Server - Node-Red automations

Installation:

Install nodejs and node-red

• sudo apt update
• sudo apt install nodejs
• sudo apt install npm
• sudo npm install -g --unsafe-perm node-red

Run node-red at system boot

Configuration of PM2

PM2 is a process manager for Node.js. It makes it easy to run applications on boot and ensure they are restarted if necessary.

• sudo npm install -g pm2 Tell PM2 to run on boot
• pm2 startup systemd Remove (deinstall)init script via:
• pm2 unstartup systemd

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Install local mosquitto broker

About mosquitto

Eclipse Mosquitto is an open source message broker that implements the MQTT protocol.

The MQTT protocol provides a lightweight method of carrying out messaging using a publish/subscribe model. This makes it suitable for Internet of Things messaging such as with low power sensors or mobile devices such as phones, embedded computers or microcontrollers.

This will implement a local mqtt-broker for the node-red flows. After installtion, you should see the following log information at node-red startup: [info] [mqtt-broker:localhost] Connected to broker: mqtt://localhost:1883

Installation steps on ubuntu 20.04

• sudo apt-add-repository ppa:mosquitto-dev/mosquitto-ppa
• sudo apt-get update
• sudo apt-get install mosquitto
• sudo apt-get install mosquitto-clients
• sudo apt clean

Configure the python environment

Approach

For our projects, we would like to be able to execute python scripts from node-red. After testing several options, we decided to go for
node-red-contrib-pythonshell. It allows us to maintain and test the code outside of node-red, which gives the flexibility to keep the code within the node-red project or maintain it in separate git repositories. Input to the node will become the argument for the python script, output of the script will be sent to output of the node.

Creating a virtual environment

The node-red-contrib-pythonshell requires the use of a virtual environment, which is a self-contained directory tree that contains a Python installation for a particular version of Python, plus a number of additional packages. Here is an example of how to create a virtual environment under the node-red project.

• apt-get install python3-venv (you need to install python3-venv when doing it for the first time)
• cd ~/.node-red/projects/<your project>
• mkdir py-src
• python3 -m venv .
• source ./bin/activate Now you can install all the modules needed for your project.