add measurement lib

libMeasurement.py

@@ -0,0 +1,135 @@
+#!/usr/bin/python
+
+
+import re
+import os
+import argparse
+import subprocess
+
+from numpy import min, max, median, mean, std
+
+
+class Measurement(object):
+    def __init__(self, interface, ofp=None, cali=(1.0, 0.0)):
+        self.outf = None
+        self.interface = interface
+        self.config_fp = '/tmp/config_entry'
+        if ofp:
+            try:
+                self.outf = open(ofp, 'w')
+            except Exception as e:
+                print(str(e))
+        self.regex = (
+            r"Target: (([0-9a-f]{2}:*){6}), " +
+            r"status: ([0-9]), rtt: ([0-9\-]+) psec, " +
+            r"distance: ([0-9\-]+) cm"
+        )
+        self.cali = cali
+
+    def prepare_config_file(self, targets):
+        if not isinstance(targets, dict):
+            return False
+        with open(self.config_fp, 'w') as of:
+            for bssid in targets:
+                of.write(
+                    "{0} bw={1} cf={2} retries=5 asap\n".format(
+                        bssid,
+                        targets[bssid]['bw'],
+                        targets[bssid]['cf']
+                    )
+                )
+        return True
+
+    def get_distance_once(self):
+        p = subprocess.Popen(
+            "iw wlp58s0 measurement ftm_request " +
+            "{0}".format(self.config_fp),
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+            shell=True
+        )
+        out, err = p.communicate()
+        if err:
+            print(err)
+            return []
+        matches = re.finditer(self.regex, out)
+        if not matches:
+            return []
+        result = []
+        for match in matches:
+            mac = match.group(1)
+            status = int(match.group(3))
+            rtt = int(match.group(4))
+            raw_distance = int(match.group(5))
+            if status is not 0 or raw_distance < -1000:
+                continue
+            distance = self.cali[0] * raw_distance + self.cali[1]
+            result.append((mac, distance, rtt, raw_distance))
+        return result
+
+    def get_distance_avg(self, rounds=10):
+        result = {}
+        avg_result = {}
+        for i in range(rounds):
+            for each in self.get_distance_once():
+                if each[0] not in result:
+                    result[each[0]] = []
+                result[each[0]].append(each[1:])
+        for mac in result:
+            avg_result[mac] = median([x[0] for x in result[mac]])
+        return avg_result
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, exc_type, exc_value, traceback):
+        # properly close the file when destroying the object
+        if self.outf is not None:
+            self.outf.close()
+
+
+def wrapper(args):
+    args['config_entry'] = {
+        '34:f6:4b:5e:69:1f': {
+            'bw': 20,
+            'cf': 2462
+        }
+    }
+    with Measurement(
+        args['interface'],
+        ofp=args['filepath'], cali=args['cali']
+    ) as m:
+        m.prepare_config_file(args['config_entry'])
+        # print(m.get_distance_once())
+        print(m.get_distance_avg())
+
+
+def main():
+    p = argparse.ArgumentParser(description='iw measurement tool')
+    p.add_argument(
+        '--cali',
+        nargs=2,
+        default=(0.9084, 526.8163),
+        type=float,
+        help="calibrate final result"
+    )
+    p.add_argument(
+        '--filepath', '-f',
+        default=None,
+        help="if set, will write raw fetched data to file"
+    )
+    p.add_argument(
+        '--interface', '-i',
+        default='wlp58s0',
+        help="set the wireless interface"
+    )
+    try:
+        args = vars(p.parse_args())
+    except Exception as e:
+        print(str(e))
+        sys.exit()
+    wrapper(args)
+
+
+if __name__ == '__main__':
+    main()