Fix generic camera error when template renders to an invalid URL (#109737)

homeassistant/components/generic/camera.py

@@ -8,6 +8,7 @@ import logging
 from typing import Any
 
 import httpx
+import voluptuous as vol
 import yarl
 
 from homeassistant.components.camera import Camera, CameraEntityFeature
@@ -140,6 +141,12 @@ class GenericCamera(Camera):
             _LOGGER.error("Error parsing template %s: %s", self._still_image_url, err)
             return self._last_image
 
+        try:
+            vol.Schema(vol.Url())(url)
+        except vol.Invalid as err:
+            _LOGGER.warning("Invalid URL '%s': %s, returning last image", url, err)
+            return self._last_image
+
         if url == self._last_url and self._limit_refetch:
             return self._last_image
 

tests/components/generic/test_camera.py

@@ -70,15 +70,20 @@ async def help_setup_mock_config_entry(
 
 @respx.mock
 async def test_fetching_url(
-    hass: HomeAssistant, hass_client: ClientSessionGenerator, fakeimgbytes_png
+    hass: HomeAssistant,
+    hass_client: ClientSessionGenerator,
+    fakeimgbytes_png,
+    caplog: pytest.CaptureFixture,
 ) -> None:
     """Test that it fetches the given url."""
-    respx.get("http://example.com").respond(stream=fakeimgbytes_png)
+    hass.states.async_set("sensor.temp", "http://example.com/0a")
+    respx.get("http://example.com/0a").respond(stream=fakeimgbytes_png)
+    respx.get("http://example.com/1a").respond(stream=fakeimgbytes_png)
 
     options = {
         "name": "config_test",
         "platform": "generic",
-        "still_image_url": "http://example.com",
+        "still_image_url": "{{ states.sensor.temp.state }}",
         "username": "user",
         "password": "pass",
         "authentication": "basic",
@@ -101,6 +106,25 @@ async def test_fetching_url(
     resp = await client.get("/api/camera_proxy/camera.config_test")
     assert respx.calls.call_count == 2
 
+    # If the template renders to an invalid URL we return the last image from cache
+    hass.states.async_set("sensor.temp", "invalid url")
+
+    # sleep another .1 seconds to make cached image expire
+    await asyncio.sleep(0.1)
+    resp = await client.get("/api/camera_proxy/camera.config_test")
+    assert resp.status == HTTPStatus.OK
+    assert respx.calls.call_count == 2
+    assert (
+        "Invalid URL 'invalid url': expected a URL, returning last image" in caplog.text
+    )
+
+    # Restore a valid URL
+    hass.states.async_set("sensor.temp", "http://example.com/1a")
+    await asyncio.sleep(0.1)
+    resp = await client.get("/api/camera_proxy/camera.config_test")
+    assert resp.status == HTTPStatus.OK
+    assert respx.calls.call_count == 3
+
 
 @respx.mock
 async def test_image_caching(