users_resolver_v1.js

const resolvers = {

  Query: {
    users: async () => {
      try {
        let users = await User.findAll()
        let userIds = users.map( user => user.id)
        let posts = await Post.findAll({where: {userId: userIds}});

        let usersData = users.map( user => {
          let userPosts = posts.filter( post => post.userId == user.id);

          return {
            id: user.id,
            name: user.name,
            email: user.email,
            posts: userPosts.map ( post => {
              return { title: post.title, description: post.description }
            })
          }
        })

        return usersData
      } catch (e) {
        console.log(e)
      }
    },
  },
};