Add support for Fixer.io (#2336)

* Add support for Fixer.io

* Add unit of measurment and set throttle to one day

.coveragerc

@@ -174,6 +174,7 @@ omit =
     homeassistant/components/sensor/efergy.py
     homeassistant/components/sensor/eliqonline.py
     homeassistant/components/sensor/fitbit.py
+    homeassistant/components/sensor/fixer.py
     homeassistant/components/sensor/forecast.py
     homeassistant/components/sensor/glances.py
     homeassistant/components/sensor/google_travel_time.py

homeassistant/components/sensor/fixer.py

@@ -0,0 +1,125 @@
+"""
+Currency exchange rate support that comes from fixer.io.
+
+For more details about this platform, please refer to the documentation at
+https://home-assistant.io/components/sensor.fixer/
+"""
+import logging
+from datetime import timedelta
+
+import voluptuous as vol
+
+from homeassistant.const import (CONF_PLATFORM, CONF_NAME)
+from homeassistant.helpers.entity import Entity
+from homeassistant.util import Throttle
+import homeassistant.helpers.config_validation as cv
+
+REQUIREMENTS = ['fixerio==0.1.1']
+
+_LOGGER = logging.getLogger(__name__)
+
+DEFAULT_NAME = "Exchange rate"
+ICON = 'mdi:currency'
+
+CONF_BASE = 'base'
+CONF_TARGET = 'target'
+
+STATE_ATTR_BASE = 'Base currency'
+STATE_ATTR_TARGET = 'Target currency'
+STATE_ATTR_EXCHANGE_RATE = 'Exchange rate'
+
+PLATFORM_SCHEMA = vol.Schema({
+    vol.Required(CONF_PLATFORM): 'fixer',
+    vol.Optional(CONF_BASE): cv.string,
+    vol.Optional(CONF_NAME): cv.string,
+    vol.Required(CONF_TARGET): cv.string,
+})
+
+# Return cached results if last scan was less then this time ago.
+MIN_TIME_BETWEEN_UPDATES = timedelta(days=1)
+
+
+def setup_platform(hass, config, add_devices, discovery_info=None):
+    """Setup the Fixer.io sensor."""
+    from fixerio import (Fixerio, exceptions)
+
+    name = config.get(CONF_NAME, DEFAULT_NAME)
+    base = config.get(CONF_BASE, 'USD')
+    target = config.get(CONF_TARGET)
+
+    try:
+        Fixerio(base=base, symbols=[target], secure=True).latest()
+    except exceptions.FixerioException:
+        _LOGGER.error('One of the given currencies is not supported')
+        return False
+
+    data = ExchangeData(base, target)
+    add_devices([ExchangeRateSensor(data, name, target)])
+
+
+# pylint: disable=too-few-public-methods
+class ExchangeRateSensor(Entity):
+    """Representation of a Exchange sensor."""
+
+    def __init__(self, data, name, target):
+        """Initialize the sensor."""
+        self.data = data
+        self._target = target
+        self._name = name
+        self._state = None
+        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._target
+
+    @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.rate is not None:
+            return {
+                STATE_ATTR_BASE: self.data.rate['base'],
+                STATE_ATTR_TARGET: self._target,
+                STATE_ATTR_EXCHANGE_RATE: self.data.rate['rates'][self._target]
+            }
+
+    @property
+    def icon(self):
+        """Return the icon to use in the frontend, if any."""
+        return ICON
+
+    def update(self):
+        """Get the latest data and updates the states."""
+        self.data.update()
+        self._state = round(self.data.rate['rates'][self._target], 3)
+
+
+class ExchangeData(object):
+    """Get the latest data and update the states."""
+
+    def __init__(self, base_currency, target_currency):
+        """Initialize the data object."""
+        from fixerio import Fixerio
+
+        self.rate = None
+        self.base_currency = base_currency
+        self.target_currency = target_currency
+        self.exchange = Fixerio(base=self.base_currency,
+                                symbols=[self.target_currency],
+                                secure=True)
+
+    @Throttle(MIN_TIME_BETWEEN_UPDATES)
+    def update(self):
+        """Get the latest data from Fixer.io."""
+        self.rate = self.exchange.latest()

requirements_all.txt

@@ -73,6 +73,9 @@ feedparser==5.2.1
 # homeassistant.components.sensor.fitbit
 fitbit==0.2.2
 
+# homeassistant.components.sensor.fixer
+fixerio==0.1.1
+
 # homeassistant.components.notify.free_mobile
 freesms==0.1.0