"""Support for Modbus Register sensors."""
import logging
import struct
from typing import Any, Optional, Union
from pymodbus.exceptions import ConnectionException, ModbusException
from pymodbus.pdu import ExceptionResponse
import voluptuous as vol
from homeassistant.components.sensor import DEVICE_CLASSES_SCHEMA, PLATFORM_SCHEMA
from homeassistant.const import (
CONF_DEVICE_CLASS,
CONF_NAME,
CONF_OFFSET,
CONF_SLAVE,
CONF_STRUCTURE,
CONF_UNIT_OF_MEASUREMENT,
)
from homeassistant.helpers import config_validation as cv
from homeassistant.helpers.restore_state import RestoreEntity
from . import CONF_HUB, DEFAULT_HUB, DOMAIN as MODBUS_DOMAIN
_LOGGER = logging.getLogger(__name__)
CONF_COUNT = "count"
CONF_DATA_TYPE = "data_type"
CONF_PRECISION = "precision"
CONF_REGISTER = "register"
CONF_REGISTER_TYPE = "register_type"
CONF_REGISTERS = "registers"
CONF_REVERSE_ORDER = "reverse_order"
CONF_SCALE = "scale"
DATA_TYPE_CUSTOM = "custom"
DATA_TYPE_FLOAT = "float"
DATA_TYPE_INT = "int"
DATA_TYPE_UINT = "uint"
DEFAULT_REGISTER_TYPE_HOLDING = "holding"
DEFAULT_REGISTER_TYPE_INPUT = "input"
def number(value: Any) -> Union[int, float]:
"""Coerce a value to number without losing precision."""
if isinstance(value, int):
return value
if isinstance(value, str):
try:
value = int(value)
return value
except (TypeError, ValueError):
pass
try:
value = float(value)
return value
except (TypeError, ValueError):
raise vol.Invalid(f"invalid number {value}")
PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend(
{
vol.Required(CONF_REGISTERS): [
{
vol.Required(CONF_NAME): cv.string,
vol.Required(CONF_REGISTER): cv.positive_int,
vol.Optional(CONF_COUNT, default=1): cv.positive_int,
vol.Optional(CONF_DATA_TYPE, default=DATA_TYPE_INT): vol.In(
[DATA_TYPE_INT, DATA_TYPE_UINT, DATA_TYPE_FLOAT, DATA_TYPE_CUSTOM]
),
vol.Optional(CONF_DEVICE_CLASS): DEVICE_CLASSES_SCHEMA,
vol.Optional(CONF_HUB, default=DEFAULT_HUB): cv.string,
vol.Optional(CONF_OFFSET, default=0): number,
vol.Optional(CONF_PRECISION, default=0): cv.positive_int,
vol.Optional(
CONF_REGISTER_TYPE, default=DEFAULT_REGISTER_TYPE_HOLDING
): vol.In([DEFAULT_REGISTER_TYPE_HOLDING, DEFAULT_REGISTER_TYPE_INPUT]),
vol.Optional(CONF_REVERSE_ORDER, default=False): cv.boolean,
vol.Optional(CONF_SCALE, default=1): number,
vol.Optional(CONF_SLAVE): cv.positive_int,
vol.Optional(CONF_STRUCTURE): cv.string,
vol.Optional(CONF_UNIT_OF_MEASUREMENT): cv.string,
}
]
}
)
def setup_platform(hass, config, add_entities, discovery_info=None):
"""Set up the Modbus sensors."""
sensors = []
data_types = {DATA_TYPE_INT: {1: "h", 2: "i", 4: "q"}}
data_types[DATA_TYPE_UINT] = {1: "H", 2: "I", 4: "Q"}
data_types[DATA_TYPE_FLOAT] = {1: "e", 2: "f", 4: "d"}
for register in config[CONF_REGISTERS]:
structure = ">i"
if register[CONF_DATA_TYPE] != DATA_TYPE_CUSTOM:
try:
structure = ">{}".format(
data_types[register[CONF_DATA_TYPE]][register[CONF_COUNT]]
)
except KeyError:
_LOGGER.error(
"Unable to detect data type for %s sensor, try a custom type",
register[CONF_NAME],
)
continue
else:
structure = register.get(CONF_STRUCTURE)
try:
size = struct.calcsize(structure)
except struct.error as err:
_LOGGER.error("Error in sensor %s structure: %s", register[CONF_NAME], err)
continue
if register[CONF_COUNT] * 2 != size:
_LOGGER.error(
"Structure size (%d bytes) mismatch registers count (%d words)",
size,
register[CONF_COUNT],
)
continue
hub_name = register[CONF_HUB]
hub = hass.data[MODBUS_DOMAIN][hub_name]
sensors.append(
ModbusRegisterSensor(
hub,
register[CONF_NAME],
register.get(CONF_SLAVE),
register[CONF_REGISTER],
register[CONF_REGISTER_TYPE],
register.get(CONF_UNIT_OF_MEASUREMENT),
register[CONF_COUNT],
register[CONF_REVERSE_ORDER],
register[CONF_SCALE],
register[CONF_OFFSET],
structure,
register[CONF_PRECISION],
register.get(CONF_DEVICE_CLASS),
)
)
if not sensors:
return False
add_entities(sensors)
class ModbusRegisterSensor(RestoreEntity):
"""Modbus register sensor."""
def __init__(
self,
hub,
name,
slave,
register,
register_type,
unit_of_measurement,
count,
reverse_order,
scale,
offset,
structure,
precision,
device_class,
):
"""Initialize the modbus register sensor."""
self._hub = hub
self._name = name
self._slave = int(slave) if slave else None
self._register = int(register)
self._register_type = register_type
self._unit_of_measurement = unit_of_measurement
self._count = int(count)
self._reverse_order = reverse_order
self._scale = scale
self._offset = offset
self._precision = precision
self._structure = structure
self._device_class = device_class
self._value = None
self._available = True
async def async_added_to_hass(self):
"""Handle entity which will be added."""
state = await self.async_get_last_state()
if not state:
return
self._value = state.state
@property
def state(self):
"""Return the state of the sensor."""
return self._value
@property
def name(self):
"""Return the name of the sensor."""
return self._name
@property
def unit_of_measurement(self):
"""Return the unit of measurement."""
return self._unit_of_measurement
@property
def device_class(self) -> Optional[str]:
"""Return the device class of the sensor."""
return self._device_class
@property
def available(self) -> bool:
"""Return True if entity is available."""
return self._available
def update(self):
"""Update the state of the sensor."""
try:
if self._register_type == DEFAULT_REGISTER_TYPE_INPUT:
result = self._hub.read_input_registers(
self._slave, self._register, self._count
)
else:
result = self._hub.read_holding_registers(
self._slave, self._register, self._count
)
except ConnectionException:
self._set_unavailable()
return
if isinstance(result, (ModbusException, ExceptionResponse)):
self._set_unavailable()
return
registers = result.registers
if self._reverse_order:
registers.reverse()
byte_string = b"".join([x.to_bytes(2, byteorder="big") for x in registers])
val = struct.unpack(self._structure, byte_string)[0]
val = self._scale * val + self._offset
if isinstance(val, int):
self._value = str(val)
if self._precision > 0:
self._value += "." + "0" * self._precision
else:
self._value = f"{val:.{self._precision}f}"
self._available = True
def _set_unavailable(self):
"""Set unavailable state and log it as an error."""
if not self._available:
return
_LOGGER.error(
"No response from hub %s, slave %s, address %s",
self._hub.name,
self._slave,
self._register,
)
self._available = False