wifisetup

#!/usr/bin/env python

from __future__ import absolute_import, division, print_function

import os
import re

import dbus

NM_NAME_PREFIX = 'org.freedesktop.NetworkManager'
NM_PATH_PREFIX = '/org/freedesktop/NetworkManager'


def get_configured_networks():
    """Return a list of configured SSIDs

    (Assume that SSID is a sufficient identifier)

    This will start its own GLib event loop, so don't call it if there's
    already one.
    """
    ssids = []

    bus = dbus.SystemBus()
    settings_proxy = bus.get_object(
        NM_NAME_PREFIX, NM_PATH_PREFIX + '/Settings')
    connections = (dbus.Interface(settings_proxy, dbus.PROPERTIES_IFACE).
                   Get(NM_NAME_PREFIX + '.Settings', 'Connections'))
    for path in connections:
        connection_proxy = bus.get_object(
            NM_NAME_PREFIX, path)
        connection_settings = (dbus.Interface(
            connection_proxy, NM_NAME_PREFIX + '.Settings.Connection').
            GetSettings(byte_arrays=True))
        if connection_settings['connection']['type'] != '802-11-wireless':
            continue
        ssids.append(str(connection_settings['802-11-wireless']['ssid']))

    return ssids

def create_network(ssid, psk):
    conn = {
        'connection': {
            'id': 'wifisetup-{}'.format(re.sub('[^0-9A-Za-z]+', '', ssid)),
            'type': '802-11-wireless',
        },
        '802-11-wireless': {
            'ssid': dbus.ByteArray(ssid),
            'hidden': True,  # just in case
        },
        'ipv4': {
            'method': 'auto',
        },
        'ipv6': {
            'method': 'auto',
        },
    }

    if psk:
        conn['802-11-wireless-security'] = {
            'auth-alg': 'open',
            'key-mgmt': 'wpa-psk',
            'psk': psk,
        }

    bus = dbus.SystemBus()
    settings_proxy = bus.get_object(
        NM_NAME_PREFIX, NM_PATH_PREFIX + '/Settings')
    dbus.Interface(
        settings_proxy, NM_NAME_PREFIX + ".Settings").AddConnection(conn)

def main():
    actual_networks = set(get_configured_networks())

    # look for networks in the environment
    desired_networks = []
    for k, v in os.environ.items():
        if not k.startswith('WIFISETUP_'):
            continue
        ssid = k[len('WIFISETUP_'):]
        if ssid in actual_networks:
            continue
        psk = v if v != '' else None
        desired_networks.append((ssid, psk))

    for (ssid, psk) in desired_networks:
        create_network(ssid, psk)

if __name__ == '__main__':
    main()