Missing query_root when no permissions are set

My use case is simply based on having a single mutation for unauthenticated users which basically is an action to signUp/signIn. There is no access to any data.

When running an introspection query in such a case, the `query_root` does not exist at all which is trouble for some external tools.

By spec, the query_root should be always defined even if empty.

http://spec.graphql.org/draft/#sec-Root-Operation-Types


Viable, workaround seems to set permissions to unauthenticated role without any fields. I've verified that GraphQL Playground can handle that well. However, tools like `graphql-code-generator` still have a problem with that for some reason.

> "query_root" defined in resolvers, but not in schema

Start with the introspection query and the schema/resolver handling for query_root, comparing the generated schema with the GraphQL root-operation specification. Done means introspection exposes an empty query_root when no permissions are set, while the unauthenticated mutation remains available.

Written by the indexing model from the issue text.