wlan.py

import machine
import time
import os
from network import WLAN
import socket
import binascii

known_nets_dict = {
    # 'ssid2': {'pwd': 'password2', 'wlan_config':  ('10.0.0.114', '255.255.0.0', '10.0.0.1', '10.0.0.1')}, # (ip, subnet_mask, gateway, DNS_server)
    'openwireless.org': {'pwd': '', 'sec': 0},
}
try:
    import wlan_config
except:
    print('failed to import wlan_config')

w = None
connection = ""
IP = ""

def wlan_init():
    global w
    if w is not None:
        #print('already initialized')
        return w
    print("Initialise WiFi")
    w = WLAN() #antenna=WLAN.EXT_ANT)
    try:
        w.hostname(binascii.hexlify(machine.unique_id()) + "." + os.uname().sysname + "." + "w")
        # hostname is not available in 1.18.2
    except:
        pass
    # print("ap_mac", binascii.hexlify(w.mac().ap_mac))
    # print("sta_mac", binascii.hexlify(w.mac().sta_mac))
    if ( w.mode() == WLAN.AP ):
        print("switch from AP to STA_AP")
        w.mode(WLAN.STA_AP)
    # original_ssid = w.ssid()
    # original_auth = w.auth()
    return w

def wlan_isconnected():
    return w.isconnected()

def wlan_waitconnected(timeout_s):
    if w is None:
        print("wlan not initialized")
        return False
    t = time.ticks_ms()
    ct = 0;
    # while not w.isconnected():
    #     ct += 1
    #     print(".", end="")
    #     machine.idle()  # save power while waiting
    #     time.sleep_ms(200)
    print('Connecting: -', end='')
    while True:
        if w.isconnected():
            print()
            break
        if timeout_s is not None and time.ticks_ms() - t > (timeout_s * 1000):
            print("\nTimeout")
            return False
        ct += 1
        x = ct % 3
        if x == 0:
            print('\b\\', end='')
        elif x == 1:
            print('\b/', end='')
        elif x == 2:
            print('\b-', end='')
        time.sleep_ms(100)
    print("Connected in", round((time.ticks_ms() - t) /1000,1), "seconds") # , "(", w.ifconfig(), ")")
    connection = "WLAN"
    ct = 0
    IP = w.ifconfig()[0]
    while IP == "0.0.0.0":
        ct += 1
        machine.idle()
        IP = w.ifconfig()[0]
        time.sleep_ms(100)
    print("Connected to", w.ssid(), #net_to_use,
          binascii.hexlify(w.bssid()),
          "with IP address:", IP, ct)
    host = "detectportal.firefox.com"
    print(host, socket.getaddrinfo(host, 80)[0][4][0])
    return True

def wlan_quick(net = ''):
    wlan_init()
    if not net:
        return wlan_quick('Pycom') or wlan_connect()
    else:
        # perform a quick connect, ie no scan
        if w.isconnected():
            print('already connected ({})'.format(w.ssid()))
            return True
        print("Quick connect", net)
        k = known_nets_dict[net]
        sec = k['sec']
        pwd = k['pwd']
        w.connect(net, ( sec, pwd ) )
        return wlan_waitconnected(timeout_s=10)

def wlan_connect(timeout_s = 20):
    global connection, IP, w
    wlan_init()

    if w.isconnected():
        print("currently connected ... disconnecting")
        w.disconnect()
        while w.isconnected():
            time.sleep_ms(100)

    print("Scanning for wifi networks")
    available_nets_list = w.scan()
    available_ssids_set = frozenset([n.ssid for n in available_nets_list])
    known_ssids_set = frozenset([key for key in known_nets_dict])
    # make the intersection
    usable_ssids_set = available_ssids_set & known_ssids_set
    print("available:", len(available_ssids_set))
    print("known:", len(known_ssids_set))
    print("usable:", len(usable_ssids_set))
    if (len(usable_ssids_set) == 0):
        print("No usable network found")
        print("known", known_ssids_set)
        print("available", available_ssids_set)
    else:
        try:
            net_to_use = usable_ssids_set.pop()
            print("net_to_use", net_to_use)
            net_properties = known_nets_dict[net_to_use]
            pwd = net_properties['pwd']
            sec = [e.sec for e in available_nets_list if e.ssid == net_to_use][0]
            if 'wlan_config' in net_properties:
                w.ifconfig(config=net_properties['wlan_config'])
            #print("connect", net_to_use, sec) # , pwd)
            w.connect(net_to_use, (sec, pwd))
            return wlan_waitconnected(timeout_s)

        except Exception as e:
            print("Error while trying to connect to Wlan:", e)
            return False

def wlan_ip():
    wlan_init()
    return w.ifconfig()[0]

def wlan_gw():
    wlan_init()
    return w.ifconfig()[2]

def wlan_ifconfig():
    wlan_init()
    c = w.ifconfig()# (ip, subnet_mask, gateway, DNS_server)
    print("ifconfig", c)
    return c

def wlan_deinit():
    w.deinit()

if __name__ == "__main__":
    import binascii
    import os
    uid = binascii.hexlify(machine.unique_id())
    name = os.uname().sysname.lower() + '-' + uid.decode("utf-8")[-4:]
    print(os.uname().sysname, uid, name, "main.py")
    print("sys", os.uname().sysname)
    print("unique_id", binascii.hexlify(machine.unique_id()))
    wlan_connect()
    if False:
        wlan_quick()
        machine.reset()