The function either returned None or ended without a return statement while using with flask_restful #62
Description
flask_restful supports returning None from the view function, but I am getting error this error when I use metrics for endpoint.
e.g
from flask_restful import Resource
by_path_counter = metrics.counter(
'by_path_counter', 'Request count by request paths',
labels={'path': lambda: request.path}
)
class FoodApi(Resource):
@by_path_counter
def post(self):
create_food()
return None, 200It works fine if I don't use @by_path_counter decorator, and returns null in the response.
But when I add the decorator, I get this error.
Traceback (most recent call last):
File "/home/wartner/.local/share/virtualenvs/config_service-TDer8cy_/lib/python3.8/site-packages/flask/app.py", line 1950, in full_dispatch_request
rv = self.dispatch_request()
File "/home/wartner/.local/share/virtualenvs/config_service-TDer8cy_/lib/python3.8/site-packages/flask/app.py", line 1936, in dispatch_request
return self.view_functions[rule.endpoint](**req.view_args)
File "/home/wartner/.local/share/virtualenvs/config_service-TDer8cy_/lib/python3.8/site-packages/flask_restful/__init__.py", line 468, in wrapper
resp = resource(*args, **kwargs)
File "/home/wartner/.local/share/virtualenvs/config_service-TDer8cy_/lib/python3.8/site-packages/flask/views.py", line 89, in view
return self.dispatch_request(*args, **kwargs)
File "/home/wartner/.local/share/virtualenvs/config_service-TDer8cy_/lib/python3.8/site-packages/flask_restful/__init__.py", line 583, in dispatch_request
resp = meth(*args, **kwargs)
File "/home/wartner/.local/share/virtualenvs/config_service-TDer8cy_/lib/python3.8/site-packages/prometheus_flask_exporter/__init__.py", line 633, in func
response = make_response(response)
File "/home/wartner/.local/share/virtualenvs/config_service-TDer8cy_/lib/python3.8/site-packages/flask/helpers.py", line 223, in make_response
return current_app.make_response(args)
File "/home/wartner/.local/share/virtualenvs/config_service-TDer8cy_/lib/python3.8/site-packages/flask/app.py", line 2097, in make_response
raise TypeError(
TypeError: The view function did not return a valid response. The function either returned None or ended without a return statement.
Is there any way, I can work around this? (I have to return None)
Any kind of help will be highly appreciated, thank you 🙂
Note: It works fine on other view functions where I return not None values