Add saj component (#26902)

* Add saj component

* Performed requested changes after review

* Performed requested changes after review 2

* Performed requested changes after review 3

* Black

* Bump pysaj library version

* Changes after review

* Fix flake8

* Review changes + isort

.coveragerc

@@ -558,6 +558,7 @@ omit =
     homeassistant/components/russound_rio/media_player.py
     homeassistant/components/russound_rnet/media_player.py
     homeassistant/components/sabnzbd/*
+    homeassistant/components/saj/sensor.py
     homeassistant/components/satel_integra/*
     homeassistant/components/scrape/sensor.py
     homeassistant/components/scsgate/*

CODEOWNERS

@@ -235,6 +235,7 @@ homeassistant/components/repetier/* @MTrab
 homeassistant/components/rfxtrx/* @danielhiversen
 homeassistant/components/rmvtransport/* @cgtobi
 homeassistant/components/roomba/* @pschmitt
+homeassistant/components/saj/* @fredericvl
 homeassistant/components/scene/* @home-assistant/core
 homeassistant/components/scrape/* @fabaff
 homeassistant/components/script/* @home-assistant/core

homeassistant/components/saj/__init__.py

@@ -0,0 +1 @@
+"""The saj component."""

homeassistant/components/saj/manifest.json

@@ -0,0 +1,12 @@
+{
+  "domain": "saj",
+  "name": "SAJ",
+  "documentation": "https://www.home-assistant.io/components/saj",
+  "requirements": [
+    "pysaj==0.0.9"
+  ],
+  "dependencies": [],
+  "codeowners": [
+    "@fredericvl"
+  ]
+}

homeassistant/components/saj/sensor.py

@@ -0,0 +1,202 @@
+"""SAJ solar inverter interface."""
+import asyncio
+from datetime import date
+import logging
+
+import pysaj
+import voluptuous as vol
+
+from homeassistant.components.sensor import PLATFORM_SCHEMA
+from homeassistant.const import (
+    CONF_HOST,
+    DEVICE_CLASS_POWER,
+    DEVICE_CLASS_TEMPERATURE,
+    ENERGY_KILO_WATT_HOUR,
+    EVENT_HOMEASSISTANT_START,
+    EVENT_HOMEASSISTANT_STOP,
+    MASS_KILOGRAMS,
+    POWER_WATT,
+    TEMP_CELSIUS,
+    TEMP_FAHRENHEIT,
+)
+from homeassistant.core import CALLBACK_TYPE, callback
+import homeassistant.helpers.config_validation as cv
+from homeassistant.helpers.entity import Entity
+from homeassistant.helpers.event import async_call_later
+
+_LOGGER = logging.getLogger(__name__)
+
+MIN_INTERVAL = 5
+MAX_INTERVAL = 300
+
+UNIT_OF_MEASUREMENT_HOURS = "h"
+
+SAJ_UNIT_MAPPINGS = {
+    "W": POWER_WATT,
+    "kWh": ENERGY_KILO_WATT_HOUR,
+    "h": UNIT_OF_MEASUREMENT_HOURS,
+    "kg": MASS_KILOGRAMS,
+    "°C": TEMP_CELSIUS,
+    "": None,
+}
+
+PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend({vol.Required(CONF_HOST): cv.string})
+
+
+async def async_setup_platform(hass, config, async_add_entities, discovery_info=None):
+    """Set up SAJ sensors."""
+
+    remove_interval_update = None
+
+    # Init all sensors
+    sensor_def = pysaj.Sensors()
+
+    # Use all sensors by default
+    hass_sensors = []
+
+    for sensor in sensor_def:
+        hass_sensors.append(SAJsensor(sensor))
+
+    saj = pysaj.SAJ(config[CONF_HOST])
+
+    async_add_entities(hass_sensors)
+
+    async def async_saj():
+        """Update all the SAJ sensors."""
+        tasks = []
+
+        values = await saj.read(sensor_def)
+
+        for sensor in hass_sensors:
+            state_unknown = False
+            if not values:
+                # SAJ inverters are powered by DC via solar panels and thus are
+                # offline after the sun has set. If a sensor resets on a daily
+                # basis like "today_yield", this reset won't happen automatically.
+                # Code below checks if today > day when sensor was last updated
+                # and if so: set state to None.
+                # Sensors with live values like "temperature" or "current_power"
+                # will also be reset to None.
+                if (sensor.per_day_basis and date.today() > sensor.date_updated) or (
+                    not sensor.per_day_basis and not sensor.per_total_basis
+                ):
+                    state_unknown = True
+            task = sensor.async_update_values(unknown_state=state_unknown)
+            if task:
+                tasks.append(task)
+        if tasks:
+            await asyncio.wait(tasks)
+        return values
+
+    def start_update_interval(event):
+        """Start the update interval scheduling."""
+        nonlocal remove_interval_update
+        remove_interval_update = async_track_time_interval_backoff(hass, async_saj)
+
+    def stop_update_interval(event):
+        """Properly cancel the scheduled update."""
+        remove_interval_update()  # pylint: disable=not-callable
+
+    hass.bus.async_listen_once(EVENT_HOMEASSISTANT_START, start_update_interval)
+    hass.bus.async_listen(EVENT_HOMEASSISTANT_STOP, stop_update_interval)
+
+
+@callback
+def async_track_time_interval_backoff(hass, action) -> CALLBACK_TYPE:
+    """Add a listener that fires repetitively and increases the interval when failed."""
+    remove = None
+    interval = MIN_INTERVAL
+
+    async def interval_listener(now=None):
+        """Handle elapsed interval with backoff."""
+        nonlocal interval, remove
+        try:
+            if await action():
+                interval = MIN_INTERVAL
+            else:
+                interval = min(interval * 2, MAX_INTERVAL)
+        finally:
+            remove = async_call_later(hass, interval, interval_listener)
+
+    hass.async_create_task(interval_listener())
+
+    def remove_listener():
+        """Remove interval listener."""
+        if remove:
+            remove()  # pylint: disable=not-callable
+
+    return remove_listener
+
+
+class SAJsensor(Entity):
+    """Representation of a SAJ sensor."""
+
+    def __init__(self, pysaj_sensor):
+        """Initialize the sensor."""
+        self._sensor = pysaj_sensor
+        self._state = self._sensor.value
+
+    @property
+    def name(self):
+        """Return the name of the sensor."""
+        return f"saj_{self._sensor.name}"
+
+    @property
+    def state(self):
+        """Return the state of the sensor."""
+        return self._state
+
+    @property
+    def unit_of_measurement(self):
+        """Return the unit the value is expressed in."""
+        return SAJ_UNIT_MAPPINGS[self._sensor.unit]
+
+    @property
+    def device_class(self):
+        """Return the device class the sensor belongs to."""
+        if self.unit_of_measurement == POWER_WATT:
+            return DEVICE_CLASS_POWER
+        if (
+            self.unit_of_measurement == TEMP_CELSIUS
+            or self._sensor.unit == TEMP_FAHRENHEIT
+        ):
+            return DEVICE_CLASS_TEMPERATURE
+
+    @property
+    def should_poll(self) -> bool:
+        """SAJ sensors are updated & don't poll."""
+        return False
+
+    @property
+    def per_day_basis(self) -> bool:
+        """Return if the sensors value is on daily basis or not."""
+        return self._sensor.per_day_basis
+
+    @property
+    def per_total_basis(self) -> bool:
+        """Return if the sensors value is cummulative or not."""
+        return self._sensor.per_total_basis
+
+    @property
+    def date_updated(self) -> date:
+        """Return the date when the sensor was last updated."""
+        return self._sensor.date
+
+    def async_update_values(self, unknown_state=False):
+        """Update this sensor."""
+        update = False
+
+        if self._sensor.value != self._state:
+            update = True
+            self._state = self._sensor.value
+
+        if unknown_state and self._state is not None:
+            update = True
+            self._state = None
+
+        return self.async_update_ha_state() if update else None
+
+    @property
+    def unique_id(self):
+        """Return a unique identifier for this sensor."""
+        return f"{self._sensor.name}"

requirements_all.txt

@@ -1410,6 +1410,9 @@ pyrepetier==3.0.5
 # homeassistant.components.sabnzbd
 pysabnzbd==1.1.0
 
+# homeassistant.components.saj
+pysaj==0.0.9
+
 # homeassistant.components.sony_projector
 pysdcp==1