added python script to locate linux devices with the wifi location api

optionally updates the coordinates of a custom position

tools/locate.py

@@ -0,0 +1,123 @@
+import argparse
+import json
+import os
+import re
+import subprocess
+
+import requests
+
+
+def get_from_lines(lines, keyword):
+    return next(iter(l for l in lines if l.startswith(keyword))).split(keyword)[1].strip()
+
+
+def scan(interface=None, sudo=False):
+    command = []
+    if sudo:
+        command.append('sudo')
+    command.append('iwlist')
+    if interface:
+        command.append(interface)
+    command.append('scan')
+
+    p = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+
+    output = p.communicate()[0].decode().split('Cell')[1:]
+    if not output:
+        return None
+
+    stations = []
+    for data in output:
+        lines = [l.strip() for l in data[5:].split('\n')]
+        try:
+            stations.append({
+                'bssid': get_from_lines(lines, 'Address:'),
+                'ssid': get_from_lines(lines, 'ESSID:')[1:-1],
+                'level': int(get_from_lines(lines, 'Quality=').split('=')[-1][:-4]),
+                'frequency': int(float(get_from_lines(lines, 'Frequency:').split(' ')[0]) * 1000)
+            })
+        except StopIteration:
+            pass
+
+    if not stations:
+        return []
+    return stations
+
+
+def locate(instance, interface=None, sudo=False, secret=None, api_secret=None, location_timeout=None):
+    stations = scan(interface=interface, sudo=sudo)
+    if not stations:
+        return None
+
+    url = instance
+    if url.endswith('/'):
+        url = url[0:-1]
+    url += '/api/routing/locate/'
+
+    if bool(secret) != bool(api_secret):
+        raise ValueError('secret specified but not api_secret, or vice versa')
+
+    json = {
+        'stations':  stations,
+    }
+
+    if secret and api_secret:
+        if not secret.startswith('p:'):
+            secret = 'p:' + secret
+
+        json['set_position'] = secret
+        json['secret'] = api_secret
+
+        if location_timeout:
+            json['timeout'] = int(location_timeout)
+
+    r = requests.post(url, json=json)
+    r.raise_for_status()
+    return r.json()
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(
+        description='locate yourself via the c3nav api and optionally update the coordinates of a custom position '
+                    'in c3nav')
+    parser.add_argument('--instance', '-i', metavar='https://event.c3nave.de',
+                        required=not bool(os.environ.get('C3NAV_INSTANCE', False)),
+                        default=os.environ.get('C3NAV_INSTANCE'),
+                        help='The base url of the c3nav instance to use, for example https://36c3.c3nav.de.')
+    parser.add_argument('--secret', '-s', default=os.environ.get('C3NAV_SECRET'),
+                        help='The secret of a custom position. If specified the custom position belonging to the the '
+                             'secret will be updated')
+    parser.add_argument('--apisecret', '-a', default=os.environ.get('C3NAV_APISECRET'),
+                        help='The api secret of a custom position, needed if you want to update a custom position')
+    parser.add_argument('--timeout', '-t', metavar='600', default=os.environ.get('C3NAV_LOCATION_TIMEOUT'), type=int,
+                        help='Sets this timeout in seconds on the update to the coordinates of a custom position.')
+    parser.add_argument('--sudo', action='store_true', default=bool(os.environ.get('C3NAV_USE_SUDO', False)),
+                        help='use sudo, i.e. "sudo iwlist scan"')
+    parser.add_argument('--interface', metavar='wlp1s0', default=os.environ.get('C3NAV_SCAN_INTERFACE'),
+                        help='Scan use this interface. By default all interfaces are used')
+    parser.add_argument('--quiet', '-q', action='store_true', help='don\'t output server response')
+
+    args = parser.parse_args()
+
+    if args.interface and not re.fullmatch(r'[a-zA-Z0-9_-]+', args.interface):
+        raise argparse.ArgumentError('invalid character in interface name')
+
+    if args.secret and ' ' in args.secret:
+        raise argparse.ArgumentError('invalid character in secret')
+
+    if args.apisecret and ' ' in args.apisecret:
+        raise argparse.ArgumentError('invalid character in apisecret')
+
+    if bool(args.secret) != bool(args.apisecret):
+        raise argparse.ArgumentError('secret specified but not apisecret, or vice versa')
+
+    location = locate(args.instance, interface=args.interface, sudo=args.sudo, secret=args.secret,
+                      api_secret=args.apisecret, location_timeout=args.timeout)
+
+    if location['location'] is None:
+        # no location found
+        if not args.quiet:
+            print('no location found')
+        exit(1)
+    elif not args.quiet:
+        print(json.dumps(location, sort_keys=True, indent=4))