Emoncms API now provides a Unit of Measurement (#32042)

* Emoncms API provides a Unit

The EmonCMS API has been amended to include a 'unit' as part of it's payload.  By using this information, all the sensors can be created without the need for individual sensors to be setup by type.

The change is backward compatible so if a unit type has been specified in the configuration, this will be used by default.

If no unit is pecified either by the Home Assistant configuration, or the Emoncms API, then the default of W will be used as before.

* Update sensor.py

Check the 'unit' key is in the API call. Older systems may not have that key in the payload.

* Modified approach with new configuration item

* Removed new config item

Removed the configuration item. The integration attempts to get the unit from the API.

If this fails *or* the unit key of the API is blank, either the specified unit, or the default will be used.

If approved, documentation will be updated.

* Update homeassistant/components/emoncms/sensor.py

Co-Authored-By: springstan <46536646+springstan@users.noreply.github.com>

* Update homeassistant/components/emoncms/sensor.py

Co-Authored-By: springstan <46536646+springstan@users.noreply.github.com>

* Apply suggestions from code review

* Apply suggestions from code review v2

* Update homeassistant/components/emoncms/sensor.py

Co-Authored-By: springstan <46536646+springstan@users.noreply.github.com>

* Update sensor.py

Update `config_unit`

Co-authored-by: springstan <46536646+springstan@users.noreply.github.com>

CODEOWNERS

@@ -96,6 +96,7 @@ homeassistant/components/eight_sleep/* @mezz64
 homeassistant/components/elgato/* @frenck
 homeassistant/components/elv/* @majuss
 homeassistant/components/emby/* @mezz64
+homeassistant/components/emoncms/* @borpin
 homeassistant/components/enigma2/* @fbradyirl
 homeassistant/components/enocean/* @bdurrer
 homeassistant/components/entur_public_transport/* @hfurubotten

homeassistant/components/emoncms/manifest.json

@@ -4,5 +4,5 @@
   "documentation": "https://www.home-assistant.io/integrations/emoncms",
   "requirements": [],
   "dependencies": [],
-  "codeowners": []
+  "codeowners": ["@borpin"]
 }

homeassistant/components/emoncms/sensor.py

@@ -37,7 +37,6 @@ CONF_SENSOR_NAMES = "sensor_names"
 
 DECIMALS = 2
 DEFAULT_UNIT = POWER_WATT
-
 MIN_TIME_BETWEEN_UPDATES = timedelta(seconds=5)
 
 ONLY_INCL_EXCL_NONE = "only_include_exclude_or_none"
@@ -73,7 +72,7 @@ def setup_platform(hass, config, add_entities, discovery_info=None):
     url = config.get(CONF_URL)
     sensorid = config.get(CONF_ID)
     value_template = config.get(CONF_VALUE_TEMPLATE)
-    unit_of_measurement = config.get(CONF_UNIT_OF_MEASUREMENT)
+    config_unit = config.get(CONF_UNIT_OF_MEASUREMENT)
     exclude_feeds = config.get(CONF_EXCLUDE_FEEDID)
     include_only_feeds = config.get(CONF_ONLY_INCLUDE_FEEDID)
     sensor_names = config.get(CONF_SENSOR_NAMES)
@@ -105,6 +104,12 @@ def setup_platform(hass, config, add_entities, discovery_info=None):
         if sensor_names is not None:
             name = sensor_names.get(int(elem["id"]), None)
 
+        unit = elem.get("unit")
+        if unit:
+            unit_of_measurement = unit
+        else:
+            unit_of_measurement = config_unit
+
         sensors.append(
             EmonCmsSensor(
                 hass,