Observed Concurrency in Mutation

• What is the current behavior? When I create mutations, I observe that mutations run concurrently. (which ruins my database)

• If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem via a github repo, https://repl.it or similar. I have created mutation like this

schema = graphene.Schema(query=Query, mutation=Mutation, auto_camelcase=True)

class Mutation(graphene.ObjectType):
    test = TestMutation.Field()

class TestMutation(graphene.Mutation):
    class Arguments:
        uuid = graphene.String(required=True)
        ... and more ...

    vocab_id = graphene.String()
    ... and more ...

    @staticmethod
    @mutation_jwt_required
    def mutate(parent, info, **kwargs):
        print("Enter mutation")

        ... code containing database modification and access ...
        ... race condition is detected here (enter mutation twice without exiting) ...

        print("Exit mutation")
        return TestMutation(...)

• What is the expected behavior? According to GraphQL documentation, the mutation is run in sequential execution.

• What is the motivation / use case for changing the behavior? I wonder if this behavior is intended.

• Please tell us about your environment:

  • Version:

  - flask=1.1.2
  - flask-sqlalchemy=2.4.4
  - numpy=1.20.0
  - pandas=1.2.1
  - pip=20.3.3
  - python=3.7.3
  - sqlalchemy=1.3.22
  - sqlite=3.34.0
  - pip:
    - flask-graphql==2.0.1
    - flask-graphql-auth==1.3.2
    - graphene==2.1.8
    - graphql-core==2.3.2
    - graphql-relay==2.0.1
    - graphql-server-core==1.2.0

• Platform: Ubuntu 18.04

• Other information (e.g. detailed explanation, stacktraces, related issues, suggestions how to fix, links for us to have context, eg. stackoverflow)

[KokeCacao]

Sequential means that if a mutation operation has multiple mutations in it then each will be executed after each other (which is different to a regular query where each field might be executed in parallel).

For example with this operation:

mutation {
  test() { success }
  anotherMutation() { success }
}

The test mutation will execute before anotherMutation.

Does that make sense?

Yes. It makes perfect sense. Thank you so much!

[jkimbo]

Sequential means that if a mutation operation has multiple mutations in it then each will be executed after each other (which is different to a regular query where each field might be executed in parallel).

For example with this operation:

mutation {
  test() { success }
  anotherMutation() { success }
}

The test mutation will execute before anotherMutation.

Does that make sense?