Add switchbotmeterbt plugin

plugins/sensors/switchbotmeterbt

@@ -0,0 +1,209 @@
+#!/usr/bin/env python3
+
+"""
+=head1 NAME
+
+  switchbotmeterbt - Munin plugin to monitor temperature/humidity with SwitchBot Meter BLE
+
+=head1 CONFIGURATION
+
+  Python 3 and bluepy are necessary.
+
+  Example for Ubuntu:
+    $ sudo apt install python3-pip
+    $ sudo pip3 install bluepy
+
+=head1 ENVIRONMENT VARIABLES
+
+  user            : root privilege is necessary for BLE scan
+  env.macaddr     : Mac Address(es) of SwitchBot Meter(s) separated by white-space (Required)
+  env.hcidev      : HCI device index. (Optional, default is 0)
+  env.tempunit    : Temperature unit. (Optional, default is C)
+  env.scantimeout : Timeout for BLE scan. (Optional, default is 5.0 seconds)
+
+  Example:
+    [switchbotmeterbt]
+      user  root
+      env.macaddr  aa:aa:aa:aa:aa:aa bb:bb:bb:bb:bb:bb cc:cc:cc:cc:cc:cc
+
+=head1 NOTES
+
+  For more details about SwitchBot Meter, see https://www.switch-bot.com/products/switchbot-meter
+
+=head1 AUTHOR
+
+  K.Cima https://github.com/shakemid
+
+=head1 LICENSE
+
+  GPLv2
+  SPDX-License-Identifier: GPL-2.0-only
+
+=head1 Magic markers
+
+  #%# family=contrib
+  #%# capabilities=
+
+=cut
+"""
+
+import sys
+import os
+import subprocess
+from bluepy.btle import Scanner, DefaultDelegate
+
+
+class SwitchbotScanDelegate(DefaultDelegate):
+    def __init__(self, macaddrs):
+        super().__init__()
+        self.sensorValues = {}
+        self.macaddrs = macaddrs
+
+    # Called when advertising data is received from an LE device
+    def handleDiscovery(self, dev, isNewDev, isNewData):
+        if dev.addr in self.macaddrs:
+            for (adtype, desc, value) in dev.getScanData():
+                if desc == '16b Service Data':
+                    munin_debug(value)
+                    self._decodeSensorData(dev, value)
+
+    def _decodeSensorData(self, dev, value):
+        # Extract lower 6 octets
+        valueBinary = bytes.fromhex(value[4:16])
+
+        # Refer to Meter BLE open API
+        # https://github.com/OpenWonderLabs/python-host/wiki/Meter-BLE-open-API
+        deviceType = chr(valueBinary[0] & 0b01111111)
+        battery = valueBinary[2] & 0b01111111
+        tint = valueBinary[4] & 0b01111111
+        tdec = valueBinary[3] & 0b00001111
+        temperature = tint + tdec / 10
+        isTemperatureAboveFreezing = valueBinary[4] & 0b10000000
+        if not isTemperatureAboveFreezing:
+            temperature = -temperature
+        humidity = valueBinary[5] & 0b01111111
+
+        self.sensorValues[dev.addr] = {
+            'DeviceType':  deviceType,
+            'Temperature': temperature,
+            'Humidity':    humidity,
+            'Battery':     battery,
+            'RSSI':        dev.rssi
+        }
+        munin_debug(str(self.sensorValues))
+
+
+class SwitchbotMeterPlugin():
+    def __init__(self):
+        self.params = {}
+        self.params['pluginname'] = os.path.basename(__file__)
+        self.params['macaddrs'] = [str.lower(macaddr)
+                                   for macaddr in os.getenv('macaddr').split()]
+        self.params['hcidev'] = int(os.getenv('hcidev', 0))
+        self.params['tempunit'] = os.getenv('tempunit', 'C')
+        self.params['scantimeout'] = float(os.getenv('scantimeout', 5.0))
+
+        self.graphs = {
+            'temp': {
+                'name': 'Temperature',
+                'attrs': [
+                    'graph_title SwitchBot Meter Temperature',
+                    'graph_category sensors',
+                    'graph_vlabel Temp ' + self.params['tempunit'],
+                    'graph_scale no',
+                    'graph_args --base 1000'
+                ]
+            },
+            'humid': {
+                'name': 'Humidity',
+                'attrs': [
+                    'graph_title SwitchBot Meter Humidity',
+                    'graph_category sensors',
+                    'graph_vlabel Humid %',
+                    'graph_scale no',
+                    'graph_args --base 1000'
+                ]
+            },
+            'batt': {
+                'name': 'Battery',
+                'attrs': [
+                    'graph_title SwitchBot Meter Battery',
+                    'graph_category sensors',
+                    'graph_vlabel %',
+                    'graph_scale no',
+                    'graph_args --base 1000 --lower-limit 0 --upper-limit 100'
+                ]
+            },
+            'rssi': {
+                'name': 'RSSI',
+                'attrs': [
+                    'graph_title SwitchBot Meter RSSI',
+                    'graph_category sensors',
+                    'graph_vlabel dB',
+                    'graph_scale no',
+                    'graph_args --base 1000'
+                ]
+            }
+        }
+
+    def config(self):
+        # print config
+        for k in self.graphs.keys():
+            print('multigraph ' + self.params['pluginname'] + '_' + k)
+            for line in self.graphs[k]['attrs']:
+                print(line)
+            for macaddr in self.params['macaddrs']:
+                field = macaddr.replace(':', '')
+                print(field + '.label ' + macaddr)
+
+    def fetch(self):
+        # scan to fetch data
+        scanner = Scanner(self.params['hcidev']).withDelegate(SwitchbotScanDelegate(self.params['macaddrs']))
+
+        try:
+            # sometimes it might fail
+            scanner.scan(self.params['scantimeout'])
+            for macaddr in self.params['macaddrs']:
+                check = scanner.delegate.sensorValues[macaddr]
+        except KeyError as e:
+            munin_error('retry scan for exception: ' + str(type(e)))
+            scanner.scan(self.params['scantimeout'])
+        except Exception as e:
+            munin_error('reset hci and retry scan for exception: ' + str(type(e)))
+            subprocess.call(f'hciconfig hci{self.params["hcidev"]} down && hciconfig hci{self.params["hcidev"]} up', shell=True)
+            scanner.scan(self.params['scantimeout'])
+
+        # print value
+        for k in self.graphs.keys():
+            print('multigraph ' + self.params['pluginname'] + '_' + k)
+            for macaddr in self.params['macaddrs']:
+                field = macaddr.replace(':', '')
+                try:
+                    print(field + '.value ' +
+                          str(scanner.delegate.sensorValues[macaddr][self.graphs[k]['name']]))
+                except KeyError:
+                    pass
+
+
+def munin_error(message):
+    print(message, file=sys.stderr)
+
+
+def munin_debug(message):
+    if os.getenv('MUNIN_DEBUG') == '1':
+        print('# ' + message)
+
+
+def main():
+    plugin = SwitchbotMeterPlugin()
+
+    if len(sys.argv) > 1 and sys.argv[1] == 'config':
+        plugin.config()
+        if os.getenv('MUNIN_CAP_DIRTYCONFIG') == '1':
+            plugin.fetch()
+    else:
+        plugin.fetch()
+
+
+if __name__ == '__main__':
+    main()