How can I test output of graphene when error is thrown?

Resolver:

def resolve_entity(self, info, **kwargs):
        id = kwargs.get('id')

        if id is None:
            raise GraphQLError('ID not provided')

        try:
            return Entity.objects.get(pk=id)
        except Entity.DoesNotExist:
            raise GraphQLError('Entity not found')

Entity:

    def test_single_athlete_no_id(self):
        athlete = Entity.objects.create(name='John Doe', weight=23.45,
                                         height=180)
        try:
            self.client.execute(
                '{ entity { id, name, weight, height } }')
        except:
            print('test')

I have been trying different ways (assertRaises, using try/except) but nothing is raised when there is definitely a stack trace like the following:

…An error occurred while resolving field Query.entity Traceback: … raise GraphQLError(‘ID not provided’) graphql.error.base.GraphQLError: ID not provided Traceback: … graphql.error.located_error.GraphQLLocatedError: ID not provided

Why am I not able to catch these exceptions? Am I not supposed to use exceptions for error handling?

[GasimGasimzada]

@dvndrsn My issue is that I am trying to test the error cases. And I want my error cases to catch the error and “pass” the test. Instead they are throwing errors. I think it would be logical to use logger for errors instead of printing them to the console.

[dvndrsn]

@iraj-jelo - that’s an interesting point, but maybe a separate discussion. One of the neat things about the GraphQL spec is that it allows for a partial response to a query where only the successfully resolved fields are returned!

There are a couple of things about exception handling in graphene that can be surprising (like how exceptions are automatically caught for resolvers as I mentioned above). I do wonder though why the server might encounter a missing required argument when submitting a query from your frontend - it may make sense for the frontend to ensure that the parameter is always passed through before sending the request.

Feel free to submit an issue with more details on this to chat through the concern in more depth.