Fix error in parsing DeepStack response JSON and handle cases where p…

…redictions field is missing (#6463)

frigate/detectors/plugins/deepstack.py

@@ -56,8 +56,11 @@ def detect_raw(self, tensor_input):
  )
  response_json = response.json()
  detections = np.zeros((20, 6), np.float32)
+ if response_json.get("predictions") is None:
+ logger.debug(f"Error in parsing response json: {response_json}")
+ return detections
 
- for i, detection in enumerate(response_json["predictions"]):
+ for i, detection in enumerate(response_json.get("predictions")):
  logger.debug(f"Response: {detection}")
  if detection["confidence"] < 0.4:
  logger.debug(f"Break due to confidence < 0.4")