WEB & Python GPIO access

[Lost]

Hi guys!

After moving my project from Raspberry to Orange i`ve got an issue with gpio access.

I`m using Lighttpd as webserver and running python scripts from touching buttons there.  But on armbian it doesn`t work because of permissions settings.

here is screenshot of simple script that turns on led

tried lots of google finds, but without any success.

What is wrong?

oh, i`m using pyA20 library 

Edited November 23, 2017 by Lost

[chwe]

pyA20 needs root... Does your script have it?

[Lost]

script works fine from terminal with sudo

But after i add root rights to www-data - same result

[chwe]

IMHO, sudo right scripts in your WWW folder (which is open to the internet I guess) is a nightmare, especially if the whole system is maintained by a beginner (don't get me wrong), it's not about your skills but you should also keep security in mind when you start to play with such thingies.. 

[Lost]

I understand that, thanks, but even this couldn`t help.

And it`s okay, i am really just a beginner in linux  

On RPi this problem was easily solved by:  sudo usermod -a -G gpio www-data

i`ve checked /etc/groups and /etc/gshadow files - there is no even gpio group

 

[chwe]

IMOH Armbians use case is more focused on server applications than on all this IoT stuff (whenever I do mostly IoT-stuff on my armbian boards, or maybe 'Localnet of Things'. ). You might check which rights pyA20 needs (don't need 'full sudo' I guess) to play with your GPIOs and give the user which runs your script these rights... I'm interested in your findings too (cause pyGPIO which is, in fact, pyA20 + board detection + mapping for various boards could maybe benefit from it). 

[Lost]

so, just find the solution

Not the best way, but worked for me.

For example, we need to run from web page "script.py" that uses gpio 

first, i make new executable file "*cgi" - for example "script.cgi". Inside of it just this:

#!/bin/bash
sudo ./script.py

after that use  $sudo visudo  and change line # Allow members of group sudo to execute any command

# Allow members of group sudo to execute any command
%sudo   ALL=(ALL) NOPASSWD: ALL

Now you can run "script.cgi" from WEB and python script will be executed.

this is wrong way if you care about security, i actually don`t like this finding, but for my underwater camera with step motor to look around, i think it is ok

 

Any time, if somebody know how to give access to gpio from python and web, i`m still interested in.

 

also found OPi.GPIO library that is similar to RPi.GPIO: just type ~$ sudo pip install OPi.GPIO 

[chwe]

11 minutes ago, Lost said:

this is wrong way if you care about security, i actually don`t like this finding, but for my underwater camera with step motor to look around, i think it is ok

As long as you don't have your underwater camera in a network open to others... It might be 'ok'.

But otherwise, your OPi can end as part of this various IoT-Botnets...  

Someone has access to a Linux machine (your OPi) inside your local network from the internet might be harmful to your next online banking bill...