A common problem in a service oriented architecture is needed to minimize the amount of round trips to a particular service.

Example: To render a UI view, I need to fetch a list of friends, a list of posts, and a list of notifications. All 3 of these data types (friends, posts, notifications) have users associated with them. Instead of fetching users for the 3 data types 3 separate times, I need to flatten that into a single call. I end up with something like this:

  var [posts, friends, notifs] = yield [
    getPosts(),
    getFriends(),
    getNotifs()
  ]; // executes in parallel

  var userIDs = new Set();
  userIDs.addAll(posts.map(p => p.userID));
  userIDs.addAll(friends.map(f => f.userID));
  userIDs.addAll(notifs.map(n => n.userID));

  var users = yield getUsers(userIDs.toArray());

  return {posts, friends, notifs, users};

You can see where this gets cumbersome. I have to compose one of these for every kind UI view at the root level. On the one hand it's very explicit and the flow of data is very clear, but it also means relationships between data are dupicated in more than one place (often many places).

Could GraphQL help with that scenario?