"""Support for Google Nest SDM Cameras."""
from __future__ import annotations
import asyncio
from collections.abc import Callable
import datetime
import functools
import logging
from pathlib import Path
from google_nest_sdm.camera_traits import (
CameraImageTrait,
CameraLiveStreamTrait,
RtspStream,
StreamingProtocol,
)
from google_nest_sdm.device import Device
from google_nest_sdm.device_manager import DeviceManager
from google_nest_sdm.exceptions import ApiException
from homeassistant.components.camera import Camera, CameraEntityFeature, StreamType
from homeassistant.components.stream import CONF_EXTRA_PART_WAIT_TIME
from homeassistant.config_entries import ConfigEntry
from homeassistant.core import HomeAssistant
from homeassistant.exceptions import HomeAssistantError
from homeassistant.helpers.entity import DeviceInfo
from homeassistant.helpers.entity_platform import AddEntitiesCallback
from homeassistant.helpers.event import async_track_point_in_utc_time
from homeassistant.util.dt import utcnow
from .const import DATA_DEVICE_MANAGER, DOMAIN
from .device_info import NestDeviceInfo
_LOGGER = logging.getLogger(__name__)
PLACEHOLDER = Path(__file__).parent / "placeholder.png"
# Used to schedule an alarm to refresh the stream before expiration
STREAM_EXPIRATION_BUFFER = datetime.timedelta(seconds=30)
async def async_setup_sdm_entry(
hass: HomeAssistant, entry: ConfigEntry, async_add_entities: AddEntitiesCallback
) -> None:
"""Set up the cameras."""
device_manager: DeviceManager = hass.data[DOMAIN][entry.entry_id][
DATA_DEVICE_MANAGER
]
entities = []
for device in device_manager.devices.values():
if (
CameraImageTrait.NAME in device.traits
or CameraLiveStreamTrait.NAME in device.traits
):
entities.append(NestCamera(device))
async_add_entities(entities)
class NestCamera(Camera):
"""Devices that support cameras."""
_attr_has_entity_name = True
def __init__(self, device: Device) -> None:
"""Initialize the camera."""
super().__init__()
self._device = device
self._device_info = NestDeviceInfo(device)
self._stream: RtspStream | None = None
self._create_stream_url_lock = asyncio.Lock()
self._stream_refresh_unsub: Callable[[], None] | None = None
self._attr_is_streaming = CameraLiveStreamTrait.NAME in self._device.traits
self.stream_options[CONF_EXTRA_PART_WAIT_TIME] = 3
@property
def unique_id(self) -> str:
"""Return a unique ID."""
# The API "name" field is a unique device identifier.
return f"{self._device.name}-camera"
@property
def device_info(self) -> DeviceInfo:
"""Return device specific attributes."""
return self._device_info.device_info
@property
def brand(self) -> str | None:
"""Return the camera brand."""
return self._device_info.device_brand
@property
def model(self) -> str | None:
"""Return the camera model."""
return self._device_info.device_model
@property
def supported_features(self) -> CameraEntityFeature:
"""Flag supported features."""
supported_features = CameraEntityFeature(0)
if CameraLiveStreamTrait.NAME in self._device.traits:
supported_features |= CameraEntityFeature.STREAM
return supported_features
@property
def frontend_stream_type(self) -> StreamType | None:
"""Return the type of stream supported by this camera."""
if CameraLiveStreamTrait.NAME not in self._device.traits:
return None
trait = self._device.traits[CameraLiveStreamTrait.NAME]
if StreamingProtocol.WEB_RTC in trait.supported_protocols:
return StreamType.WEB_RTC
return super().frontend_stream_type
@property
def available(self) -> bool:
"""Return True if entity is available."""
# Cameras are marked unavailable on stream errors in #54659 however nest
# streams have a high error rate (#60353). Given nest streams are so flaky,
# marking the stream unavailable has other side effects like not showing
# the camera image which sometimes are still able to work. Until the
# streams are fixed, just leave the streams as available.
return True
async def stream_source(self) -> str | None:
"""Return the source of the stream."""
if not self.supported_features & CameraEntityFeature.STREAM:
return None
if CameraLiveStreamTrait.NAME not in self._device.traits:
return None
trait = self._device.traits[CameraLiveStreamTrait.NAME]
if StreamingProtocol.RTSP not in trait.supported_protocols:
return None
async with self._create_stream_url_lock:
if not self._stream:
_LOGGER.debug("Fetching stream url")
try:
self._stream = await trait.generate_rtsp_stream()
except ApiException as err:
raise HomeAssistantError(f"Nest API error: {err}") from err
self._schedule_stream_refresh()
assert self._stream
if self._stream.expires_at < utcnow():
_LOGGER.warning("Stream already expired")
return self._stream.rtsp_stream_url
def _schedule_stream_refresh(self) -> None:
"""Schedules an alarm to refresh the stream url before expiration."""
assert self._stream
_LOGGER.debug("New stream url expires at %s", self._stream.expires_at)
refresh_time = self._stream.expires_at - STREAM_EXPIRATION_BUFFER
# Schedule an alarm to extend the stream
if self._stream_refresh_unsub is not None:
self._stream_refresh_unsub()
self._stream_refresh_unsub = async_track_point_in_utc_time(
self.hass,
self._handle_stream_refresh,
refresh_time,
)
async def _handle_stream_refresh(self, now: datetime.datetime) -> None:
"""Alarm that fires to check if the stream should be refreshed."""
if not self._stream:
return
_LOGGER.debug("Extending stream url")
try:
self._stream = await self._stream.extend_rtsp_stream()
except ApiException as err:
_LOGGER.debug("Failed to extend stream: %s", err)
# Next attempt to catch a url will get a new one
self._stream = None
if self.stream:
await self.stream.stop()
self.stream = None
return
# Update the stream worker with the latest valid url
if self.stream:
self.stream.update_source(self._stream.rtsp_stream_url)
self._schedule_stream_refresh()
async def async_will_remove_from_hass(self) -> None:
"""Invalidates the RTSP token when unloaded."""
if self._stream:
_LOGGER.debug("Invalidating stream")
try:
await self._stream.stop_rtsp_stream()
except ApiException as err:
_LOGGER.debug(
"Failed to revoke stream token, will rely on ttl: %s", err
)
if self._stream_refresh_unsub:
self._stream_refresh_unsub()
async def async_added_to_hass(self) -> None:
"""Run when entity is added to register update signal handler."""
self.async_on_remove(
self._device.add_update_listener(self.async_write_ha_state)
)
async def async_camera_image(
self, width: int | None = None, height: int | None = None
) -> bytes | None:
"""Return bytes of camera image."""
# Use the thumbnail from RTSP stream, or a placeholder if stream is
# not supported (e.g. WebRTC)
stream = await self.async_create_stream()
if stream:
return await stream.async_get_image(width, height)
return await self.hass.async_add_executor_job(self.placeholder_image)
@classmethod
@functools.cache
def placeholder_image(cls) -> bytes:
"""Return placeholder image to use when no stream is available."""
return PLACEHOLDER.read_bytes()
async def async_handle_web_rtc_offer(self, offer_sdp: str) -> str | None:
"""Return the source of the stream."""
trait: CameraLiveStreamTrait = self._device.traits[CameraLiveStreamTrait.NAME]
if StreamingProtocol.WEB_RTC not in trait.supported_protocols:
return await super().async_handle_web_rtc_offer(offer_sdp)
try:
stream = await trait.generate_web_rtc_stream(offer_sdp)
except ApiException as err:
raise HomeAssistantError(f"Nest API error: {err}") from err
return stream.answer_sdp