Utility meter (#19718)

* initial commit

* test service calls

* lint

* float -> Decimal

* extra tests

* lint

* lint

* lint

* lint

* fix self reset

* clean

* add services

* improve service example description

* add optional paused initialization

* fix

* travis fix

* fix YEARLY

* add tests for previous bug

* address comments and suggestions from @ottowinter

* lint

* remove debug

* add discoverability capabilities

* no need for _hass

* Update homeassistant/components/sensor/utility_meter.py

Co-Authored-By: dgomes <diogogomes@gmail.com>

* Update homeassistant/components/sensor/utility_meter.py

Co-Authored-By: dgomes <diogogomes@gmail.com>

* correct comment

* improve error handling

* address @MartinHjelmare comments

* address @MartinHjelmare comments

* one patch is enought

* follow @ballob suggestion in https://github.com/home-assistant/architecture/issues/131

* fix tests

* review fixes

* major refactor

* lint

* lint

* address comments by @MartinHjelmare

* rename variable

homeassistant/components/utility_meter/const.py

@@ -0,0 +1,30 @@
+"""Constants for the utility meter component."""
+DOMAIN = 'utility_meter'
+
+HOURLY = 'hourly'
+DAILY = 'daily'
+WEEKLY = 'weekly'
+MONTHLY = 'monthly'
+YEARLY = 'yearly'
+
+METER_TYPES = [HOURLY, DAILY, WEEKLY, MONTHLY, YEARLY]
+
+DATA_UTILITY = 'utility_meter_data'
+
+CONF_METER = 'meter'
+CONF_SOURCE_SENSOR = 'source'
+CONF_METER_TYPE = 'cycle'
+CONF_METER_OFFSET = 'offset'
+CONF_PAUSED = 'paused'
+CONF_TARIFFS = 'tariffs'
+CONF_TARIFF = 'tariff'
+CONF_TARIFF_ENTITY = 'tariff_entity'
+
+ATTR_TARIFF = 'tariff'
+
+SIGNAL_START_PAUSE_METER = 'utility_meter_start_pause'
+SIGNAL_RESET_METER = 'utility_meter_reset'
+
+SERVICE_RESET = 'reset'
+SERVICE_SELECT_TARIFF = 'select_tariff'
+SERVICE_SELECT_NEXT_TARIFF = 'next_tariff'