How to handle properly handle graphene error?

Question

I am in the early period of graphene-django.

I have Mutation like this

class DeleteObjection(graphene.Mutation):
    """
    1. Authorized User only
    2. His own `Objection` only
    3. Be able to delete only `Hidden type Objection`
    """
    ok = graphene.Boolean()

    class Arguments:
        id = graphene.ID()

    @classmethod
    def mutate(cls, root, info, **kwargs):
        tmp = {
            **kwargs,
            'created_by': info.context.user,
            'hidden': True
        }
        obj = Objection.objects.get(**tmp)
        obj.delete()
        return cls(ok=True)

And the res is handle in like I expected. It is 200 with forwarded error right after the console

{
  "errors": [
    {
      "message": "Objection matching query does not exist.",
      "locations": [
        {
          "line": 131,
          "column": 3
        }
      ],
      "path": [
        "deleteObjection"
      ]
    }
  ],
  "data": {
    "deleteObjection": null
  }
}

Problem:
On my Python server console. I see error has been raised

Testing started at 16:01 ...
/Users/sarit/.pyenv/versions/multy_herr/bin/python "/Users/sarit/Library/Application Support/JetBrains/Toolbox/apps/PyCharm-P/ch-0/193.5662.61/PyCharm.app/Contents/plugins/python/helpers/pycharm/django_test_manage.py" test multy_herr.objections.tests_jwt.UsersTest.test_authorized_user_delete_non_exist_objection /Users/sarit/mein-codes/multy_herr
Creating test database for alias 'default'...
System check identified no issues (0 silenced).

Traceback (most recent call last):
  File "/Users/sarit/.pyenv/versions/multy_herr/lib/python3.8/site-packages/promise/promise.py", line 489, in _resolve_from_executor
    executor(resolve, reject)
  File "/Users/sarit/.pyenv/versions/multy_herr/lib/python3.8/site-packages/promise/promise.py", line 756, in executor
    return resolve(f(*args, **kwargs))
  File "/Users/sarit/.pyenv/versions/multy_herr/lib/python3.8/site-packages/graphql/execution/middleware.py", line 75, in make_it_promise
    return next(*args, **kwargs)
  File "/Users/sarit/mein-codes/multy_herr/multy_herr/objections/grapheql/mutations.py", line 36, in mutate
    obj = Objection.objects.get(**tmp)
  File "/Users/sarit/.pyenv/versions/multy_herr/lib/python3.8/site-packages/django/db/models/manager.py", line 82, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/Users/sarit/.pyenv/versions/multy_herr/lib/python3.8/site-packages/django/db/models/query.py", line 415, in get
    raise self.model.DoesNotExist(
graphql.error.located_error.GraphQLLocatedError: Objection matching query does not exist.

Destroying test database for alias 'default'...


Process finished with exit code 0

Problem:
I hate error in the Python console. Because it will alarm in the Crash Analytic and I considers it as a poor code

Attempts:
1. Add try - exception and raise it again

    @classmethod
    def mutate(cls, root, info, **kwargs):
        tmp = {
            **kwargs,
            'created_by': info.context.user,
            'hidden': True
        }
        try:
            obj = Objection.objects.get(**tmp)
        except Exception as err:

            raise Exception
        else:
            obj.delete()
            return cls(ok=True)

I got unsatisfied result

res.data
Out[3]: OrderedDict([('deleteObjection', None)])
res.errors
Out[4]: [graphql.error.located_error.GraphQLLocatedError('')]

2. Customized my own class attribute

class DeleteObjection(graphene.Mutation):
    """
    1. Authorized User only
    2. His own `Objection` only
    3. Be able to delete only `Hidden type Objection`
    """
    ok = graphene.Boolean()
    errors = graphene.List(graphene.String)

    class Arguments:
        id = graphene.ID()

    @classmethod
    def mutate(cls, root, info, **kwargs):
        tmp = {
            **kwargs,
            'created_by': info.context.user,
            'hidden': True
        }
        try:
            obj = Objection.objects.get(**tmp)
        except Exception as err:
            return cls(ok=False, errors=[err])
        else:
            obj.delete()
            return cls(ok=True)

errors does not come to the response

res.data
Out[3]: OrderedDict([('deleteObjection', OrderedDict([('ok', False)]))])
res.errors

Question:
How do I suppress the error at my Python console and follow the common Exception in graphene-django?

Answer 1

Here is how I am handling the errors in Graphene-Django.

class CreateBlog(graphene.Mutation):
   class Arguments:
      input = BlogInputType(required=True)

   ok = graphene.Boolean()
   blog = graphene.Field(BlogType)
   errors = graphene.Field(BlogErrorsInputType)

   @staticmethod
   def mutate(root, info, input):
      form = CreateBlogForm(data=input)
      if form.is_valid():
         blog = form.save()
         return CreateBlog(ok=True, blog=blog, errors=form.errors)
      return CreateBlog(ok=False, errors=form.errors)

Check out the details from here.