Add parsing code for ttnmapper by JPMeijers

To be able to draw tracker on map

python/jpmeijers.py

@@ -0,0 +1,74 @@
+#!/usr/bin/env python3
+
+# Send lora packet to node-red when being triggered by postgresql
+# Nico Schottelius <nico.schottelius -at- ungleich.ch>
+# 2016-11-02
+# GPLv3+
+
+
+import binascii
+import struct
+import lorautil
+import logging
+import sys
+
+log = logging.getLogger(__name__)
+log.setLevel(logging.DEBUG)
+
+known_devices = [ "0004A30B001C6613" ]
+
+def convert_gps_from_stdin():
+    for line in sys.stdin:
+        res = get_gps("", line)
+        if res:
+            print(res[0][1:])
+
+# Parsing code from jpmeiyers
+def get_gps(deveui, payload):
+    res = []
+    data = binascii.a2b_base64(payload)
+
+    if(len(data)!=9):
+        return res
+
+    parsed = struct.unpack("<BBBBBBBBB", data)
+    values = {}
+    values['lat'] = (parsed[0]*(2**16) + parsed[1]*(2**8) + parsed[2])/16777215.0*180.0-90
+    values['lon'] = (parsed[3]*(2**16) + parsed[4]*(2**8) + parsed[5])/16777215.0*360.0-180
+    values['alt'] = parsed[6]*(2**8) + parsed[7]
+    values['acc'] = parsed[8]/10.0
+
+    pos = ":lat={lat:.6f} lon={lon:.6f} alt={alt:.6f} acc={acc:.2f}.format(**values)
+    res = [ deveui + pos ]
+
+    return res
+
+def decode(pkg):
+    data = pkg.split(":")
+
+    deveui = data[0]
+    payload = data[1]
+
+    res = []
+
+    # Only handle known devices
+    if not deveui in known_devices:
+        return res
+
+    res += get_gps(deveui, payload)
+
+    return res
+
+def nodered(provider, data):
+    res = decode(data)
+    if not res:
+        return
+
+    for d in res:
+        lorautil.nodered_send(provider, d)
+
+if __name__ == '__main__':
+    conns = lorautil.pg_conn_notify()
+
+    while True:
+        lorautil.pg_wait_for_pkg(conns, nodered)