Initial commit of snmp device tracker

homeassistant/components/device_tracker/snmp.py

@@ -0,0 +1,125 @@
+"""
+homeassistant.components.device_tracker.demo
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Fetch wifi associations through snmp
+
+device_tracker:
+  platform: snmp
+  host: YOUR_WAP_IP
+  community: SNMP_COMMUNITY
+  baseoid: BASE_OID
+
+
+Little help with base oids:
+    Microtik: 1.3.6.1.4.1.14988.1.1.1.2.1.1 (confirmed)
+    Aruba: 1.3.6.1.4.1.14823.2.3.3.1.2.4.1.2 (untested)
+
+"""
+import logging
+from datetime import timedelta
+import threading
+import binascii
+
+from homeassistant.const import CONF_HOST, CONF_COMMUNITY, CONF_BASEOID
+from homeassistant.helpers import validate_config
+from homeassistant.util import Throttle
+from homeassistant.components.device_tracker import DOMAIN
+
+MIN_TIME_BETWEEN_SCANS = timedelta(seconds=5)
+
+_LOGGER = logging.getLogger(__name__)
+REQUIREMENTS = ['pysnmp']
+
+def setup_scanner(hass, config):
+    """ Setup snmp scanning """
+    if not validate_config(config,
+                           {DOMAIN: [CONF_HOST, CONF_COMMUNITY, CONF_BASEOID]},
+                           _LOGGER):
+        return None
+
+    scanner = SnmpScanner(config[DOMAIN])
+
+    return scanner if scanner.success_init else None
+
+
+class SnmpScanner(object):
+    """ This class queries any SNMP capable Acces Point for connected devices. """
+    def __init__(self, config):
+        self.host = config[CONF_HOST]
+        self.community = config[CONF_USERNAME]
+        self.baseoid = config[CONF_BASEOID]
+
+        self.lock = threading.Lock()
+
+        self.last_results = []
+
+        # Test the router is accessible
+        data = self.get_snmp_data()
+        self.success_init = data is not None
+
+    def scan_devices(self):
+        """
+        Scans for new devices and return a list containing found device IDs.
+        """
+
+        self._update_info()
+        return self.last_results
+
+    def get_device_name(self, device):
+        """ Returns the name of the given device or None if we don't know. """
+        return None
+
+    @Throttle(MIN_TIME_BETWEEN_SCANS)
+    def _update_info(self):
+        """
+        Ensures the information from the WAP is up to date.
+        Returns boolean if scanning successful.
+        """
+        if not self.success_init:
+            return False
+
+        with self.lock:
+            data = self.get_snmp_data()
+            if not data:
+                return False
+
+            self.last_results = data
+            return True
+
+    def get_snmp_data(self):
+        """ Fetch mac addresses from WAP via SNMP. """
+        devices = []
+
+
+        from pysnmp.entity.rfc3413.oneliner import cmdgen
+
+        oid='1.3.6.1.4.1.14988.1.1.1.2.1.1'
+        cmdGen = cmdgen.CommandGenerator()
+
+        errorIndication, errorStatus, errorIndex, varBindTable = cmdGen.nextCmd(
+            cmdgen.CommunityData( self.community ),
+            cmdgen.UdpTransportTarget( ( self.host , 161) ),
+            cmdgen.MibVariable( self.baseoid )
+        )
+
+        if errorIndication:
+            _LOGGER.exception( "SNMPLIB error: {}".format( errorIndication ) )
+            return
+        else:
+            if errorStatus:
+                _LOGGER.exception( "SNMP error: {} at {}".format( errorStatus.prettyPrint(), errorIndex and varBindTable[-1][int(errorIndex)-1] or '?' ) )
+                return
+            else:
+                for varBindTableRow in varBindTable:
+                    for val in varBindTableRow.values():
+                        devices.append( convertMac( val ) )
+        return devices
+
+    def convertMac(octect):
+        ''' Convert a binary mac address to a string '''
+        mac = []
+        for x in list(octet):
+            mac.append(binascii.b2a_hex(x))
+        return ":".join(mac)
+