Influxdb sensor (#4060)

* Influxdb sensor with voluptuous configuration validation

* Adding sensor to coveragerc since there is no test for now

.coveragerc

@@ -253,6 +253,7 @@ omit =
     homeassistant/components/sensor/gtfs.py
     homeassistant/components/sensor/haveibeenpwned.py
     homeassistant/components/sensor/hp_ilo.py
+    homeassistant/components/sensor/influxdb.py
     homeassistant/components/sensor/imap.py
     homeassistant/components/sensor/imap_email_content.py
     homeassistant/components/sensor/lastfm.py

homeassistant/components/sensor/influxdb.py

@@ -0,0 +1,181 @@
+"""
+InfluxDB component which allows you to get data from an Influx database.
+
+For more details about this component, please refer to the documentation at
+https://home-assistant.io/components/sensor.influxdb/
+"""
+import logging
+from datetime import timedelta
+
+import voluptuous as vol
+from homeassistant.components.sensor import PLATFORM_SCHEMA
+from homeassistant.const import (CONF_HOST, CONF_PORT, CONF_USERNAME,
+                                 CONF_PASSWORD, CONF_SSL, CONF_VERIFY_SSL,
+                                 CONF_NAME, CONF_UNIT_OF_MEASUREMENT,
+                                 CONF_VALUE_TEMPLATE)
+from homeassistant.const import STATE_UNKNOWN
+from homeassistant.util import Throttle
+
+from homeassistant.helpers.entity import Entity
+import homeassistant.helpers.config_validation as cv
+
+_LOGGER = logging.getLogger(__name__)
+
+DEFAULT_HOST = 'localhost'
+DEFAULT_PORT = 8086
+DEFAULT_DATABASE = 'home_assistant'
+DEFAULT_SSL = False
+DEFAULT_VERIFY_SSL = False
+DEFAULT_GROUP_FUNCTION = 'mean'
+DEFAULT_FIELD = 'value'
+
+CONF_DB_NAME = 'database'
+CONF_QUERIES = 'queries'
+CONF_GROUP_FUNCTION = 'group_function'
+CONF_FIELD = 'field'
+CONF_MEASUREMENT_NAME = 'measurement'
+CONF_WHERE = 'where'
+
+REQUIREMENTS = ['influxdb==3.0.0']
+
+_QUERY_SCHEME = vol.Schema({
+    vol.Required(CONF_NAME): cv.string,
+    vol.Required(CONF_UNIT_OF_MEASUREMENT): cv.string,
+    vol.Required(CONF_MEASUREMENT_NAME): cv.string,
+    vol.Required(CONF_WHERE): cv.string,
+    vol.Optional(CONF_VALUE_TEMPLATE): cv.template,
+    vol.Optional(CONF_DB_NAME, default=DEFAULT_DATABASE): cv.string,
+    vol.Optional(CONF_GROUP_FUNCTION, default=DEFAULT_GROUP_FUNCTION):
+        cv.string,
+    vol.Optional(CONF_FIELD, default=DEFAULT_FIELD): cv.string,
+})
+
+PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend({
+    vol.Required(CONF_QUERIES): [_QUERY_SCHEME],
+    vol.Optional(CONF_HOST, default=DEFAULT_HOST): cv.string,
+    vol.Optional(CONF_PORT, default=DEFAULT_PORT): cv.port,
+    vol.Inclusive(CONF_USERNAME, 'authentication'): cv.string,
+    vol.Inclusive(CONF_PASSWORD, 'authentication'): cv.string,
+    vol.Optional(CONF_SSL, default=DEFAULT_SSL): cv.boolean,
+    vol.Optional(CONF_VERIFY_SSL, default=DEFAULT_VERIFY_SSL): cv.boolean
+})
+
+# Return cached results if last scan was less then this time ago
+MIN_TIME_BETWEEN_UPDATES = timedelta(seconds=60)
+
+
+def setup_platform(hass, config, add_devices, discovery_info=None):
+    """Setup the InfluxDB component."""
+    influx_conf = {'host': config[CONF_HOST],
+                   'port': config.get(CONF_PORT),
+                   'username': config.get(CONF_USERNAME),
+                   'password': config.get(CONF_PASSWORD),
+                   'ssl': config.get(CONF_SSL),
+                   'verify_ssl': config.get(CONF_VERIFY_SSL)}
+
+    dev = []
+
+    for query in config.get(CONF_QUERIES):
+        sensor = InfluxSensor(hass, influx_conf, query)
+        if sensor.connected:
+            dev.append(sensor)
+
+    add_devices(dev)
+
+
+class InfluxSensor(Entity):
+    """Implementation of a Influxdb sensor."""
+
+    def __init__(self, hass, influx_conf, query):
+        """Initialize the sensor."""
+        from influxdb import InfluxDBClient, exceptions
+        self._name = query.get(CONF_NAME)
+        self._unit_of_measurement = query.get(CONF_UNIT_OF_MEASUREMENT)
+        value_template = query.get(CONF_VALUE_TEMPLATE)
+        if value_template is not None:
+            self._value_template = value_template
+            self._value_template.hass = hass
+        else:
+            self._value_template = None
+        database = query.get(CONF_DB_NAME)
+        self._state = None
+        self._hass = hass
+        formated_query = "select {}({}) as value from {} where {}"\
+            .format(query.get(CONF_GROUP_FUNCTION),
+                    query.get(CONF_FIELD),
+                    query.get(CONF_MEASUREMENT_NAME),
+                    query.get(CONF_WHERE))
+        influx = InfluxDBClient(host=influx_conf['host'],
+                                port=influx_conf['port'],
+                                username=influx_conf['username'],
+                                password=influx_conf['password'],
+                                database=database,
+                                ssl=influx_conf['ssl'],
+                                verify_ssl=influx_conf['verify_ssl'])
+        try:
+            influx.query("select * from /.*/ LIMIT 1;")
+            self.connected = True
+            self.data = InfluxSensorData(influx, formated_query)
+            self.update()
+        except exceptions.InfluxDBClientError as exc:
+            _LOGGER.error("Database host is not accessible due to '%s', please"
+                          " check your entries in the configuration file and"
+                          " that the database exists and is READ/WRITE.", exc)
+            self.connected = False
+
+    @property
+    def name(self):
+        """Return the name of the sensor."""
+        return self._name
+
+    @property
+    def state(self):
+        """Return the state of the sensor."""
+        return self._state
+
+    @property
+    def unit_of_measurement(self):
+        """Unit of measurement of this entity, if any."""
+        return self._unit_of_measurement
+
+    @property
+    def should_poll(self):
+        """Polling needed."""
+        return True
+
+    def update(self):
+        """Get the latest data from influxdb and updates the states."""
+        self.data.update()
+        value = self.data.value
+        if value is None:
+            value = STATE_UNKNOWN
+        if self._value_template is not None:
+            value = self._value_template.render_with_possible_json_value(
+                str(value), STATE_UNKNOWN)
+
+        self._state = value
+
+
+# pylint: disable=too-few-public-methods
+class InfluxSensorData(object):
+    """Class for handling the data retrieval."""
+
+    def __init__(self, influx, query):
+        """Initialize the data object."""
+        self.influx = influx
+        self.query = query
+        self.value = None
+
+    @Throttle(MIN_TIME_BETWEEN_UPDATES)
+    def update(self):
+        """Get the latest data with a shell command."""
+        _LOGGER.info('Running query: %s', self.query)
+
+        points = list(self.influx.query(self.query).get_points())
+        if len(points) == 0:
+            _LOGGER.error('Query returned no points : %s', self.query)
+            return
+        if len(points) > 1:
+            _LOGGER.warning('Query returned multiple points, only first one'
+                            ' shown : %s', self.query)
+        self.value = points[0].get('value')

requirements_all.txt

@@ -230,6 +230,7 @@ https://github.com/web-push-libs/pywebpush/archive/e743dc92558fc62178d255c001892
 https://github.com/wokar/pylgnetcast/archive/v0.2.0.zip#pylgnetcast==0.2.0
 
 # homeassistant.components.influxdb
+# homeassistant.components.sensor.influxdb
 influxdb==3.0.0
 
 # homeassistant.components.insteon_hub