function instrumentResolvers(resolvers, getCurrentHub) {
  return resolvers.map(model => {
    Object.keys(model).forEach(resolverGroupName => {
      Object.keys(model[resolverGroupName]).forEach(resolverName => {
        if (typeof model[resolverGroupName][resolverName] !== 'function') {
          return;
        }

        wrapResolver(model, resolverGroupName, resolverName, getCurrentHub);
      });
    });

    return model;
  });
}
Iterate over resolvers of the ApolloServer instance before schemas are constructed.