inputTypes-3.js

const userMutations = {
  createUser: {
    type: UserType,
    args: {
      input: {
        type: new GraphQLNonNull(UserInputType),
      },
    },
    resolve: async (rootValue, { input }) => {
      if (input.email && !isEmail(input.email)) {
        throw new Error('Email is not in valid format');
      }
      const result = await new Promise((resolve) => {
        setTimeout(() =>
          resolve(Object.assign(input, {
            id: random.uuid(),
          })), 100);
      });
      return result;
    },
  },
};