core/homeassistant/components/file/sensor.py

90 lines
2.7 KiB
Python

"""Support for sensor value(s) stored in local files."""
from __future__ import annotations
import logging
import os
from file_read_backwards import FileReadBackwards
from homeassistant.components.sensor import SensorEntity
from homeassistant.config_entries import ConfigEntry
from homeassistant.const import (
CONF_FILE_PATH,
CONF_NAME,
CONF_UNIT_OF_MEASUREMENT,
CONF_VALUE_TEMPLATE,
)
from homeassistant.core import HomeAssistant
from homeassistant.helpers.entity_platform import AddEntitiesCallback
from homeassistant.helpers.template import Template
from .const import DEFAULT_NAME, FILE_ICON
_LOGGER = logging.getLogger(__name__)
async def async_setup_entry(
hass: HomeAssistant,
entry: ConfigEntry,
async_add_entities: AddEntitiesCallback,
) -> None:
"""Set up the file sensor."""
config = dict(entry.data)
options = dict(entry.options)
file_path: str = config[CONF_FILE_PATH]
unique_id: str = entry.entry_id
name: str = config.get(CONF_NAME, DEFAULT_NAME)
unit: str | None = options.get(CONF_UNIT_OF_MEASUREMENT)
value_template: Template | None = None
if CONF_VALUE_TEMPLATE in options:
value_template = Template(options[CONF_VALUE_TEMPLATE], hass)
async_add_entities(
[FileSensor(unique_id, name, file_path, unit, value_template)], True
)
class FileSensor(SensorEntity):
"""Implementation of a file sensor."""
_attr_icon = FILE_ICON
def __init__(
self,
unique_id: str,
name: str,
file_path: str,
unit_of_measurement: str | None,
value_template: Template | None,
) -> None:
"""Initialize the file sensor."""
self._attr_name = name
self._file_path = file_path
self._attr_native_unit_of_measurement = unit_of_measurement
self._val_tpl = value_template
self._attr_unique_id = unique_id
def update(self) -> None:
"""Get the latest entry from a file and updates the state."""
try:
with FileReadBackwards(self._file_path, encoding="utf-8") as file_data:
for line in file_data:
data = line
break
data = data.strip()
except (IndexError, FileNotFoundError, IsADirectoryError, UnboundLocalError):
_LOGGER.warning(
"File or data not present at the moment: %s",
os.path.basename(self._file_path),
)
return
if self._val_tpl is not None:
self._attr_native_value = (
self._val_tpl.async_render_with_possible_json_value(data, None)
)
else:
self._attr_native_value = data