Tado device tracker support (#5046)

* Added tado device tracker

* Added tado device tracker to .converagerc

* Updated docs

* Code formatting and removed unused import

* Code formatting and removed unused import

* Respected the lint line length

* Respect pydocstyle rules

* Respect the lint line limit length

* Fixed reviewer feedback

* Changed the tracker to support async

* Respect the New line end of file rule

* Update .coveragerc

.coveragerc

@@ -168,6 +168,7 @@ omit =
     homeassistant/components/device_tracker/swisscom.py
     homeassistant/components/device_tracker/thomson.py
     homeassistant/components/device_tracker/tomato.py
+    homeassistant/components/device_tracker/tado.py
     homeassistant/components/device_tracker/tplink.py
     homeassistant/components/device_tracker/trackr.py
     homeassistant/components/device_tracker/ubus.py

homeassistant/components/device_tracker/tado.py

@@ -0,0 +1,130 @@
+"""
+Support for Tado Smart Thermostat.
+
+Device tracker platform that supports presence detection.
+The detection is based on geofencing enabled devices used with Tado.
+"""
+import logging
+from datetime import timedelta
+from collections import namedtuple
+
+import asyncio
+import aiohttp
+import async_timeout
+
+import voluptuous as vol
+
+from homeassistant.const import CONF_USERNAME, CONF_PASSWORD
+import homeassistant.helpers.config_validation as cv
+from homeassistant.util import Throttle
+from homeassistant.components.device_tracker import \
+    DOMAIN, PLATFORM_SCHEMA, DeviceScanner
+from homeassistant.helpers.aiohttp_client import async_create_clientsession
+
+# Return cached results if last scan was less then this time ago
+MIN_TIME_BETWEEN_SCANS = timedelta(seconds=30)
+
+_LOGGER = logging.getLogger(__name__)
+
+PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend({
+    vol.Required(CONF_PASSWORD): cv.string,
+    vol.Required(CONF_USERNAME): cv.string
+})
+
+
+def get_scanner(hass, config):
+    """Return a Tado scanner."""
+    scanner = TadoDeviceScanner(hass, config[DOMAIN])
+
+    return scanner if scanner.success_init else None
+
+
+Device = namedtuple("Device", ["mac", "name"])
+
+
+class TadoDeviceScanner(DeviceScanner):
+    """This class gets geofenced devices from Tado."""
+
+    def __init__(self, hass, config):
+        """Initialize the scanner."""
+        self.last_results = []
+
+        self.username = config[CONF_USERNAME]
+        self.password = config[CONF_PASSWORD]
+        self.tadoapiurl = 'https://my.tado.com/api/v2/me' \
+                          '?username={}&password={}'
+
+        self.websession = async_create_clientsession(
+            hass, cookie_jar=aiohttp.CookieJar(unsafe=True, loop=hass.loop))
+
+        self.success_init = self._update_info()
+        _LOGGER.info("Tado scanner initialized")
+
+    @asyncio.coroutine
+    def async_scan_devices(self):
+        """Scan for devices and return a list containing found device ids."""
+        yield from self._update_info()
+
+        return [device.mac for device in self.last_results]
+
+    @asyncio.coroutine
+    def async_get_device_name(self, mac):
+        """Return the name of the given device or None if we don't know."""
+        filter_named = [device.name for device in self.last_results
+                        if device.mac == mac]
+
+        if filter_named:
+            return filter_named[0]
+        else:
+            return None
+
+    @Throttle(MIN_TIME_BETWEEN_SCANS)
+    def _update_info(self):
+        """
+        Query Tado for device marked as at home.
+
+        Returns boolean if scanning successful.
+        """
+        _LOGGER.debug("Requesting Tado")
+
+        last_results = []
+
+        response = None
+        tadojson = None
+        try:
+            # get first token
+            with async_timeout.timeout(10, loop=self.hass.loop):
+                url = self.tadoapiurl.format(self.username, self.password)
+                response = yield from self.websession.get(
+                    url
+                )
+
+                # error on Tado webservice
+                if response.status != 200:
+                    _LOGGER.warning(
+                        "Error %d on %s.", response.status, self.tadoapiurl)
+                    self.token = None
+                    return
+
+                tadojson = yield from response.json()
+
+        except (asyncio.TimeoutError, aiohttp.errors.ClientError):
+            _LOGGER.error("Can not load Tado data")
+            return False
+
+        finally:
+            if response is not None:
+                yield from response.release()
+
+        # Find devices that have geofencing enabled, and are currently at home
+        for mobiledevice in tadojson['mobileDevices']:
+            if 'location' in mobiledevice:
+                if mobiledevice['location']['atHome']:
+                    deviceid = mobiledevice['id']
+                    devicename = mobiledevice['name']
+                    last_results.append(Device(deviceid, devicename))
+
+        self.last_results = last_results
+
+        _LOGGER.info("Tado presence query successful")
+        return True