Improve content type handling in ImageEntity (#95365)

homeassistant/components/image/__init__.py

@@ -62,9 +62,9 @@ class ImageContentTypeError(HomeAssistantError):
     """Error with the content type while loading an image."""
 
 
-def valid_image_content_type(content_type: str) -> str:
+def valid_image_content_type(content_type: str | None) -> str:
     """Validate the assigned content type is one of an image."""
-    if content_type.split("/", 1)[0] != "image":
+    if content_type is None or content_type.split("/", 1)[0] != "image":
         raise ImageContentTypeError
     return content_type
 
@@ -174,9 +174,10 @@ class ImageEntity(Entity):
                 url, timeout=GET_IMAGE_TIMEOUT, follow_redirects=True
             )
             response.raise_for_status()
+            content_type = response.headers.get("content-type")
             return Image(
                 content=response.content,
-                content_type=response.headers["content-type"],
+                content_type=valid_image_content_type(content_type),
             )
         except httpx.TimeoutException:
             _LOGGER.error("%s: Timeout getting image from %s", self.entity_id, url)
@@ -189,6 +190,14 @@ class ImageEntity(Entity):
                 err,
             )
             return None
+        except ImageContentTypeError:
+            _LOGGER.error(
+                "%s: Image from %s has invalid content type: %s",
+                self.entity_id,
+                url,
+                content_type,
+            )
+            return None
 
     async def async_image(self) -> bytes | None:
         """Return bytes of image."""

tests/components/image/test_init.py

@@ -256,3 +256,34 @@ async def test_fetch_image_url_exception(
 
     resp = await client.get("/api/image_proxy/image.test")
     assert resp.status == HTTPStatus.INTERNAL_SERVER_ERROR
+
+
+@respx.mock
+@pytest.mark.parametrize(
+    "content_type",
+    [
+        None,
+        "text/plain",
+    ],
+)
+async def test_fetch_image_url_wrong_content_type(
+    hass: HomeAssistant,
+    hass_client: ClientSessionGenerator,
+    content_type: str | None,
+) -> None:
+    """Test fetching an image with an authenticated client."""
+    respx.get("https://example.com/myimage.jpg").respond(
+        status_code=HTTPStatus.OK, content_type=content_type, content=b"Test"
+    )
+
+    mock_integration(hass, MockModule(domain="test"))
+    mock_platform(hass, "test.image", MockImagePlatform([MockURLImageEntity(hass)]))
+    assert await async_setup_component(
+        hass, image.DOMAIN, {"image": {"platform": "test"}}
+    )
+    await hass.async_block_till_done()
+
+    client = await hass_client()
+
+    resp = await client.get("/api/image_proxy/image.test")
+    assert resp.status == HTTPStatus.INTERNAL_SERVER_ERROR