Oneshot middleware

Hi! Currently I’m trying to add some one-shot-middlewares to the graphene schema (e.g. version check, policy check). The problem is, that the middleware get’s fired for each field instead for a single request. I can’t use the DjangoMiddlewares because the error doesn’t get wrapped into the graphql response error field

I found 2 solutions for this problem:

1. I set a variable _skip=False in the middleware which is toggled to True before the first next(...) call, e.g.:

lass LatestPolicyAcceptedMiddleware:

    def __init__(self, *args, **kwargs):
        super(LatestPolicyAcceptedMiddleware, self).__init__(*args, **kwargs)
        self._skip = False

    def resolve(self, next, root, info, **kwargs):
        if self._skip:
            return next(root, info, **kwargs)
        ...
        self._skip = True
        return next(root, info, **kwargs)

Well - that works but feels really odd.

1. Patching the GraphQLView.get_response method like this:

    def get_response(self, request, data, show_graphiql=False):
        try:
            check_min_native_version(request)
            latest_policy_check(request)
            return super(PatchedGraphQLView, self).get_response(request, data, show_graphiql)
        except (PolicyRequiredException, UpgradeNeededException) as e:
            result = self.json_encode(request, {"errors": [self.format_error(e)], "data": None}, pretty=show_graphiql)
            status_code = e.code
            return result, status_code

This feels also odd, but a way cleaner.

So - what’s the best way to integrate a one-time middleware? It feels like the framework is missing this essential feature.

[melvinkcx]

Graphene middleware is called at a field-level, each field resolution would trigger calls to all middleware. I’m not sure if graphene will support request-level middleware, I just created an issue: https://github.com/graphql-python/graphene/issues/1117

For now, what I do is add an attribute into info.context object and toggle that to indicate should the middleware logic be executed.

class AuthMiddleware:
    def resolve(self, next, root, info, **kwargs):
        if not hasattr(info.context, "auth_checked") and info.context.auth_checked:
            # Check user auth
            info.context.auth_checked = True
            
        return next(root, info, **kwargs)

[melvinkcx]

@richin13 @MrFoxes This issue is fixed and is now available in graphql-utilities>=0.2.0.