Merge pull request #8 from CopterExpress/wifi_signal_handler

Wifi data handler

clever/src/web_server.py

@@ -1,12 +1,12 @@
 #!/usr/bin/env python
 
 import rospy
-from flask import Flask, send_from_directory, send_file
-
+import subprocess
+import re
+from flask import Flask, send_from_directory, send_file, request, jsonify
 
 rospy.init_node('web_server', disable_signals=True)
 
-
 port = rospy.get_param('~port', 7070)
 host = rospy.get_param('~host', '0.0.0.0')
 serve_path = rospy.get_param('~path')
@@ -24,5 +24,37 @@ def serve_static(path):
     return send_from_directory(serve_path, path)
 
 
+@app.route('/wifi_data/')
+def get_wifi_data():
+    cur_ip = request.remote_addr
+    ip_signal = get_ip_signal()
+    return jsonify({'ip': cur_ip, 'signal': ip_signal[cur_ip]}), 200
+
+
+def get_ip_signal():
+    wlan_interface = 'wlan0'
+    # Getting info about wifi client connected to access point. From here we know MAC and signal level
+    iwl = subprocess.check_output(['sudo', 'iw', 'dev', 'wlan0', 'station', 'dump']).splitlines()
+    mac_signal = {}
+    cur_client = ''
+    for line in iwl:
+        if line.find('Station') != -1:
+            cur_client = re.search(r'([0-9A-F]{2}[:-]){5}([0-9A-F]{2})', line, re.I).group()
+        if line.find('signal') != -1:
+            sg = re.search(r'(\[-?\d*\])', line, re.I).group()
+            mac_signal[cur_client] = re.sub(r'[\[\]]', '', sg)
+    ip_signal = {}
+    # Getting ip-mac mapping
+    ip_mac = subprocess.check_output(['arp', '-i', wlan_interface]).splitlines()
+    for line in ip_mac:
+        mac = re.search(r'([0-9A-F]{2}[:-]){5}([0-9A-F]{2})', line, re.I)
+        if mac is not None:
+            mac = mac.group()
+            if mac in mac_signal:
+                ips = re.search(r'((2[0-5]|1[0-9]|[0-9])?[0-9]\.){3}((2[0-5]|1[0-9]|[0-9])?[0-9])', line, re.I).group()
+                ip_signal[ips] = mac_signal[mac]
+    return ip_signal
+
+
 rospy.loginfo('Serving on %s:%s', host, port)
 app.run(host=host, port=port, threaded=True)