I'm trying to use an MQTT broker to broadcast some data. For flexibility, I want to set the MQTT variables in the system environment and then read them in my Node-Red flow. It used to work (some years ago) but no longer does. Here's a simple example showing this. Working context: Node-RED versi…

OK -- success. Here are the details: (1) I've now modified the EnvironmentFile contents to remove export from the beginning of each line. user@RP01:~$ cat ~/.node-red/EnvironmentFile MQTT_BROKER=broker.hivemq.com MQTT_PORT=1883 MQTT_CLIENT_ID=Client007 MQTT_TOPIC=ViewMe/Meter01 MQTT_NAME=MyName (…

None of that is necessary. Just enter the parameters in the MQTT config node setup using this syntax ${ENVVAR}. it's all in the docs: Using environment variables : Node-RED

This might be helpfull, some stuff I only just discovered: There are several ways to define environment variables for Node-red. One approach (on Linux) is to declare them in a file .node-red/EnvironmentFile (the filename is specified in /etc/systemd/system/multi-user.target.wants/nodered.service")…

My attempts are still failing. The variables are set in the shell immediately before starting node-red, as confirmed by the command set | grep MQTT. I then follow instructions in the Using environment variables . For example, those instructions state: Within a Function node, environment variables …

OK my apologies, the Raspberry install script for Node-red does setup systemd but unless you run sudo systemctl enable nodered they are not accessible in that directory. Enabling makes a link so that Node-red is automatically started at boot. I always do this. pi@zero2green:/etc/systemd/system/mult…

[image] ThisEndUp: The variables are set in the shell immediately before starting node-red Are you exporting the variables? EVERYTHING=42 sets the variable, while export EVERYTHING=42 makes it available in subshells

If you set an environment variable in a shell window it only affects processes run from that terminal. If you were to start node red using node-red Then it should be accessible in node red. However, by using node-red-start you are telling systemd to start node red, it is not running within your te…

Many thanks. I've found something that does work and some things that don't. What does work: I returned ~/.node-red/settings.js to its original contents. I followed jbudd's advice and ran sudo systemctl enable nodered and I created a file to set variables in ~/.node-red/EnvironmentFile. user@RP0…

[image] ThisEndUp: What does not work: (1) setting variables in ~/.node-red/ That's a surprise because as I showed in my first post above, it works for me. I don't have "export" in that file though, that's a bashism and I presume this file is interpreted by JavaScript. Maybe it only works …

What have you got in EnvironmentFile?

It's listed in my response. [image] ThisEndUp: user@RP01:~$ cat ~/.node-red/EnvironmentFile export MQTT_BROKER=broker.hivemq.com export MQTT_PORT=1883 export MQTT_CLIENT_ID=Client007 export MQTT_TOPIC=ViewMe/Meter01 export MQTT_NAME=MyName But I did try it once without the export a…

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Accessing environment variables

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jbudd 19 March 2024 16:47 16

Unfortunately the Node-red documentation on environment variables is wrong.

https://discourse.nodered.org/t/error-in-user-guide/86486

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Accessing environment variables

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