Problem with EXEC node and command line parameters

[Tontze]

Im trying to execute and get output to debug node. My command is :

sudo python3 read_wavemini.py 2920004430 10

It looks like it does not understand command line options:

2.4.2021 klo 13.33.41node: 734014ef.7c82a4
msg.payload : string[54]
string[54]

usage: read_wavemini [-h] SERIAL_NUMBER SAMPLE_PERIOD

2.4.2021 klo 13.33.41node: 734014ef.7c82a4msg.payload : string[60]
string[60]

read_wavemini: error: unrecognized arguments: 1617359621080

2.4.2021 klo 13.33.41node: 734014ef.7c82a4msg.payload : Object
object
code: 2

It runs, if i disable msg.payload, but then i dont get anything to any outputs of the exec node ?
When it runs, it stays on and tries to report things, so im using spawn mode.

Can someone explain me how to make it work ?

-T

[Colin]

Add a debug node showing what is going into the exec node and show us (screenshot) how you have configured the exec node.

[dceejay]

Under normal usage you can’t use sudo in an exec node as that is a escalation of privileges exception. To run an app as sudo you need either run the whole of node-red as root or allow the app (python) to have admin privileges.

[Tontze]

@Colin i have only inject node before exec node. @dceejay i have setup my system so that sudo is not asking password for user im using, isnt that enough ?

[{"id":"734014ef.7c82a4","type":"debug","z":"e1366dff.7c47f8","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":1390,"y":820,"wires":[]},{"id":"d66801d6.8e86f","type":"inject","z":"e1366dff.7c47f8","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"","payloadType":"date","x":820,"y":820,"wires":[["7bdb1043.f2bec8"]]},{"id":"7bdb1043.f2bec8","type":"exec","z":"e1366dff.7c47f8","command":"sudo python3 read_wavemini.py 2920004430 5","addpay":true,"append":"","useSpawn":"true","timer":"","oldrc":false,"name":"","x":1080,"y":820,"wires":[["734014ef.7c82a4"],["734014ef.7c82a4"],["734014ef.7c82a4"]]}]

This is what is coming out from the .py :

Temperature: 24.42 *C, Humidity: 29.46 %rH, VOC: 101 ppm

[Tontze]

i c that i propably need to format inject node somehow, but how ?) exec node doesnt need any parameters, just needs to run.

Im still learning ..

[Tontze]

Hm ok, empty inject node seems to do the work

[E1cid]

@Tontze

You were appending msg.payload to your command. So you where adding 1617359621080 to the end of your command , as msg.payload was a timestamp.

[Colin]

By telling it to append msg.payload then it will add the timestamp to the end of the command, so the command it runs will be something like
sudo python3 read_wavemini.py 2920004430 5 1617366502827
Is that what you want?

When you run it in a terminal do you just execute the command and the answer appears immediately or do you have to enter something via the keyboard?

[Tontze]

No it really wasnt what i wanted in console, i just run that command, nothing more needed. It stays running and outputs once in a while.

[Colin]

So is it all working now?

[Tontze]

Yes it is, thank you all for helping