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HTML / CSS / JS

// Resolver signature: (parent, args, context, info) => value | Promise<value>

// Type resolvers — parent is the resolved User object
  User: {
    // Computed field: not stored in DB
    fullName: (user) => `${user.firstName} ${user.lastName}`,

// Relation: load posts for this user
    posts: async (user, { limit }, { db }) => {
      return db.posts.findAll({ where: { authorId: user.id }, limit });
    },

// Hide sensitive data based on context
    email: (user, _, { currentUser }) => {
      if (currentUser?.id === user.id || currentUser?.role === 'ADMIN') {
        return user.email;
      }
      return null;
    },
  },

Post: {
    // Resolve author from authorId stored on post
    author: (post, _, { db }) => db.users.findById(post.authorId),
    wordCount: (post) => post.body.split(/\s+/).length,
  },
};