Add support for hydrological data from FOEN (#2318)

.coveragerc

@@ -187,6 +187,7 @@ omit =
     homeassistant/components/sensor/speedtest.py
     homeassistant/components/sensor/steam_online.py
     homeassistant/components/sensor/supervisord.py
+    homeassistant/components/sensor/swiss_hydrological_data.py
     homeassistant/components/sensor/swiss_public_transport.py
     homeassistant/components/sensor/systemmonitor.py
     homeassistant/components/sensor/temper.py

homeassistant/components/sensor/swiss_hydrological_data.py

@@ -0,0 +1,163 @@
+"""
+Support for hydrological data from the Federal Office for the Environment FOEN.
+
+For more details about this platform, please refer to the documentation at
+https://home-assistant.io/components/sensor.swiss_hydrological_data/
+"""
+import logging
+import collections
+from datetime import timedelta
+
+import voluptuous as vol
+import requests
+
+from homeassistant.const import (TEMP_CELSIUS, CONF_PLATFORM, CONF_NAME)
+import homeassistant.helpers.config_validation as cv
+from homeassistant.helpers.entity import Entity
+from homeassistant.util import Throttle
+
+REQUIREMENTS = ['beautifulsoup4==4.4.1', 'lxml==3.6.0']
+
+_LOGGER = logging.getLogger(__name__)
+_RESOURCE = 'http://www.hydrodaten.admin.ch/en/'
+
+DEFAULT_NAME = 'Water temperature'
+CONF_STATION = 'station'
+ICON = 'mdi:cup-water'
+
+ATTR_DISCHARGE = 'Discharge'
+ATTR_WATERLEVEL = 'Level'
+ATTR_DISCHARGE_MEAN = 'Discharge mean'
+ATTR_WATERLEVEL_MEAN = 'Level mean'
+ATTR_TEMPERATURE_MEAN = 'Temperature mean'
+ATTR_DISCHARGE_MAX = 'Discharge max'
+ATTR_WATERLEVEL_MAX = 'Level max'
+ATTR_TEMPERATURE_MAX = 'Temperature max'
+
+PLATFORM_SCHEMA = vol.Schema({
+    vol.Required(CONF_PLATFORM): 'swiss_hydrological_data',
+    vol.Optional(CONF_NAME): cv.string,
+    vol.Required(CONF_STATION): cv.string,
+})
+
+HydroData = collections.namedtuple(
+    "HydrologicalData",
+    ['discharge', 'waterlevel', 'temperature', 'discharge_mean',
+     'waterlevel_mean', 'temperature_mean', 'discharge_max', 'waterlevel_max',
+     'temperature_max'])
+
+# Return cached results if last scan was less then this time ago.
+MIN_TIME_BETWEEN_UPDATES = timedelta(seconds=120)
+
+
+def setup_platform(hass, config, add_devices, discovery_info=None):
+    """Setup the Swiss hydrological sensor."""
+    station = config.get(CONF_STATION)
+    name = config.get(CONF_NAME, DEFAULT_NAME)
+
+    try:
+        response = requests.get('{}/{}.html'.format(_RESOURCE, station),
+                                timeout=5)
+        if not response.ok:
+            _LOGGER.error('The given station does not seem to exist: %s',
+                          station)
+            return False
+    except requests.exceptions.ConnectionError:
+        _LOGGER.error('The URL is not accessible')
+        return False
+
+    data = HydrologicalData(station)
+    add_devices([SwissHydrologicalDataSensor(name, data)])
+
+
+# pylint: disable=too-few-public-methods
+class SwissHydrologicalDataSensor(Entity):
+    """Implementation of an Swiss hydrological sensor."""
+
+    def __init__(self, name, data):
+        """Initialize the sensor."""
+        self.data = data
+        self._name = name
+        self._unit_of_measurement = TEMP_CELSIUS
+        self.update()
+
+    @property
+    def name(self):
+        """Return the name of the sensor."""
+        return self._name
+
+    @property
+    def unit_of_measurement(self):
+        """Return the unit of measurement of this entity, if any."""
+        return self._unit_of_measurement
+
+    @property
+    def state(self):
+        """Return the state of the sensor."""
+        return self._state
+
+    @property
+    def device_state_attributes(self):
+        """Return the state attributes."""
+        if self.data.measurings is not None:
+            return {
+                ATTR_DISCHARGE: self.data.measurings.discharge,
+                ATTR_WATERLEVEL: self.data.measurings.waterlevel,
+                ATTR_DISCHARGE_MEAN: self.data.measurings.discharge_mean,
+                ATTR_WATERLEVEL_MEAN: self.data.measurings.waterlevel_mean,
+                ATTR_TEMPERATURE_MEAN: self.data.measurings.temperature_mean,
+                ATTR_DISCHARGE_MAX: self.data.measurings.discharge_max,
+                ATTR_WATERLEVEL_MAX: self.data.measurings.waterlevel_max,
+                ATTR_TEMPERATURE_MAX: self.data.measurings.temperature_max,
+            }
+
+    @property
+    def icon(self):
+        """Icon to use in the frontend, if any."""
+        return ICON
+
+    # pylint: disable=too-many-branches
+    def update(self):
+        """Get the latest data and update the states."""
+        self.data.update()
+        if self.data.measurings is not None:
+            self._state = self.data.measurings.temperature
+
+
+# pylint: disable=too-few-public-methods
+class HydrologicalData(object):
+    """The Class for handling the data retrieval."""
+
+    def __init__(self, station):
+        """Initialize the data object."""
+        self.station = station
+        self.measurings = None
+
+    @Throttle(MIN_TIME_BETWEEN_UPDATES)
+    def update(self):
+        """Get the latest data from hydrodaten.admin.ch."""
+        from bs4 import BeautifulSoup
+
+        try:
+            response = requests.get('{}/{}.html'.format(_RESOURCE,
+                                                        self.station),
+                                    timeout=5)
+        except requests.exceptions.ConnectionError:
+            _LOGGER.error('Unable to retrieve data')
+            response = None
+
+        try:
+            tables = BeautifulSoup(response.content,
+                                   'lxml').findChildren('table')
+            rows = tables[0].findChildren(['th', 'tr'])
+
+            details = []
+
+            for row in rows:
+                cells = row.findChildren('td')
+                for cell in cells:
+                    details.append(cell.string)
+
+            self.measurings = HydroData._make(details)
+        except AttributeError:
+            self.measurings = None

requirements_all.txt

@@ -31,6 +31,9 @@ apcaccess==0.0.4
 # homeassistant.components.sun
 astral==1.2
 
+# homeassistant.components.sensor.swiss_hydrological_data
+beautifulsoup4==4.4.1
+
 # homeassistant.components.light.blinksticklight
 blinkstick==1.1.7
 
@@ -171,6 +174,9 @@ lightify==1.0.3
 # homeassistant.components.light.limitlessled
 limitlessled==1.0.0
 
+# homeassistant.components.sensor.swiss_hydrological_data
+lxml==3.6.0
+
 # homeassistant.components.notify.message_bird
 messagebird==1.2.0