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I'm working on a project where a mobile app can find and pair with a headless raspberry pi running Pi OS (Debian Buster Port) over bluetooth, send it an ssid and password and it'll create and hop on the wifi network. Everything is working but I really don't like this code that creates the wifi connection. I need the delays in there because there's no callback that I know of for the os commands and even after they finish there is some hardware delay. Just throwing out to the hive mind if there is a better way:

os.system("nmcli connection delete {}".format(ssid))
time.sleep(2)
os.system("nmcli r wifi off")
time.sleep(2)
os.system("nmcli r wifi on")
time.sleep(5)
os.system("nmcli dev wifi rescan")
time.sleep(5)
os.system("nmcli d wifi connect \"{}\" password \"{}\"".format(ssid, pw))

using the nmcli (Network Manager Command Line Interface).

Sleep seconds are guestimates - I'm looking for a way to get a callback

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  • your question is not Raspberry Pi specific ... have you read the nmcli docs about status reporting? Commented Sep 29, 2023 at 17:59
  • It's raspberry pi specific in the sense that I'm trying to programmatically add a wifi network and it's very difficult because of the way the way Raspberry Pi OS (Debian Bullseye) manages wifi. It assumes wifi is pre-configured or set using raspi-config interface. my problems with nmcli is related to a bug apparently in this release, raspi-config can't be used to add wifi headless, Pi OS doesn't use /etc/wpa_supplicant/wpa_supplicant.conf as expected - it's a tough nut to crack.... Commented Sep 29, 2023 at 18:11
  • actually turns out this exists sudo raspi-config nonint do_wifi_ssid_passphrase <ssid> <passphrase> [hidden] [plain] so if that works i'll update the question Commented Sep 29, 2023 at 18:17
  • post an answer instead ... it would be more useful for future research Commented Sep 29, 2023 at 18:24
  • for the benefit of noobs, please do not use rant-like statements such as can't stand code like this ... give an explanation instead ... maybe something like event driven code would be less prone to errors Commented Sep 29, 2023 at 18:28

1 Answer 1

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Here's the solution. It's important to know that you can use raspi-config without the interface on the command line but it's not well documented so you have to look at the source code to figure some things out.

There are also several issues with using nmcli to do this. First needing to purge any lingering wifi connections like this if any were added before using it:

 nmcli --fields UUID,TIMESTAMP-REAL con show | grep never |  awk '{print $1}' | while read line; do sudo nmcli con delete uuid  $line;    done

But also it doesn't set the country code correctly on the PI which raspi-config will do. The country code is stored in several places on the pi and can even be overwritten if manually edited.

Last part was to just read up on how to wait for a command to complete in python where in my case, I was getting the ssid and password from an app connected over bluetooth.

Run a command in python and wait for it to complete:

def runAndWait(command):
    process = subprocess.Popen(command, shell=True, stdout=subprocess.PIPE)
    process.wait()
    var = process.returncode
    print(var)

add wifi:

runAndWait("ifconfig wlan0 up")
runAndWait("raspi-config nonint do_wifi_country {}".format(XX))
runAndWait("raspi-config nonint do_wifi_ssid_passphrase {} {}".format(ssid, pw))
runAndWait("ifconfig wlan0 up")

replace XX with the wlan country code e.g US, GB, AU

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  • +1 It's good to see people that can answer their own non-trivial questions. Welcome! Commented Sep 29, 2023 at 23:48

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