Image entity
An image entity can display a static image. Derive a platform entity from homeassistant.components.image.ImageEntity.
The image entity is a simplified version of the camera entity, and supports serving a static image or an image URL that can be fetched.
An implementation can provide either a URL from where an image will automatically be fetched or image data as bytes. When providing a URL, the fetched image will be cached in self._cached_image, set self._cached_image to None to invalidate the cache.
Properties
Properties should always only return information from memory and not do I/O (like network requests). Implement update() or async_update() to fetch data.
| Name | Type | Default | Description |
|---|---|---|---|
| content_type | str | image/jpeg | The content-type of the image, set automatically if the image entity provides a URL. |
| image_last_updated | datetime.datetime | None | None | Timestamp of when the image was last updated. Used to determine state. Frontend will call image or async_image after this changes. |
| image_url | str | None | UNDEFINED | Optional URL from where the image should be fetched. |
Methods
Image
Implement async_image or image if your entity returns bytes of the image instead of providing a URL. Frontend will call async_image or image to fetch the image. If the image is fetched remotely, image data should be cached and the cache invalidated when image_last_updated is changed.
Note that:
- The image entity's
async_imageorimagemethod is only called when frontend fetches the image. - Frontend will:
- Fetch the image once when a page with an image entity is loaded
- Refetch the image when the image entity's state changed by the image entity changing
image_last_updated
This means it's incorrect to bump the image_last_updated property inside async def async_image. Instead, the image entity should, when an updated image is available or periodically if the image should be refetched after some time, update the image_last_updated timestamp. This can for example happen as part of an entity coordinator update.
class MyImage(ImageEntity):
# Implement one of these methods.
def image(self) -> bytes | None:
"""Return bytes of image."""
async def async_image(self) -> bytes | None:
"""Return bytes of image."""