Raspi Connect to WIFI via Python os shell commands

Question

I'm having trouble connecting to a wifi via python script right now because most tutorials out there are deprecated. There do not seem to be suitable up-to-date python packages anymore thus I plan to use os.system(command) for connection.

But up until now I just cannot find the right method for my requirements. I want to use interface wlan0 to scan available networks and then connect to one via essid and key. I want to maintain a static IP so that I can still find the pi for ssh connection.

The whole connection thing should be rather easy e.g. via network manager nmcli but I struggle to find a right configuration for my requirements (you got to activate the interface in /etc/network/interfaces right??) without either WIFI breaking or the static IP getting lost.

It would be great if someone can recommend any up-to-date method to do this so that I do not try to get things to work which are deprecated.

Thanks in advance and best regards.

Answer 1

I could solve it myself. Here's the function I wrote which connects to a given WIFI via ssid and password. It is a bit workaround-like but it works for me so far. Just make sure that the line numbers 6 and 7 match your file structure.

def connect(goal_ssid,goal_pw):
    # "" important in wpa.conf or it would not work
    goal_ssid = '"' + goal_ssid + '"'   
    goal_pw = '"' + goal_pw + '"'
    
    # Reconfigure goal wifi and key in line 6 and 7 of wpa_supplicant.conf
    cm = "sudo sed -i '6s/.*/        ssid=" + goal_ssid + "/' /etc/wpa_supplicant/wpa_supplicant.conf" # using % does not work with all the "" being important in the wpa.conf
    os.system(cm)
    cm = "sudo sed -i '7s/.*/        psk=" + goal_pw + "/' /etc/wpa_supplicant/wpa_supplicant.conf" # using % does not work with all the "" being important in the wpa.conf
    os.system(cm)

    # Activate new configuration
    cm = "sudo wpa_cli -i wlan0 reconfigure"
    os.system(cm)