如何在Parse中獲取該對象的對象和特定關係？

Question

表

_User 
    Default user class by Parse.com 

tweet 
    objectId<string> 
    tweet<string> 
    tweetBy<string><Pointer _User> 
    createdAt<Date> 
    updatedAt<Date> 

follow 
    objectId<string> 
    following<string><Pointer _User> 
    followedBy<string> 
    createdAt<Date> 
    updatedAt<Date> 

Table data 
------------------------------------------------------------------------ 
-        _User         - 
------------------------------------------------------------------------ 
| objectId | username | password | email | createdAt | updatedAt | 
------------------------------------------------------------------------ 
| z12ttttt | Matt  | hidden | taz@taz.com |random time|random time| 
| z12zzzzz | Jobs  | hidden | anu@taz.com |random time|random time| 
| z12bbbbb | Ballu | hidden | lon@taz.com |random time|random time| 
| z12aaaaa | Stephin | hidden | zon@taz.com |random time|random time| 
------------------------------------------------------------------------ 

----------------------------------------------------------- 
-      tweet       - 
----------------------------------------------------------- 
| objectId | tweet | tweetBy | createdAt | updatedAt | 
----------------------------------------------------------- 
| blabla | Head Pain | z12ttttt |random time|random time| 
| blab12 | Back Pain | z12ttttt |random time|random time| 
| blab23 | Sleepy | z12ttttt |random time|random time| 
| blab90 | Head Pain | z12zzzzz |random time|random time| 
| blab90 | lets Dance| z12bbbbb |random time|random time| 
| blab90 | lets jump | z12aaaaa |random time|random time| 
----------------------------------------------------------- 

------------------------------------------------------------- 
-      follow        - 
------------------------------------------------------------- 
| objectId | following | followedBy | createdAt | updatedAt | 
------------------------------------------------------------- 
| blabla | z12ttttt | z12zzzzz |random time|random time| 
| blabla | z12bbbbb | z12zzzzz |random time|random time| 
------------------------------------------------------------- 

所需的輸出：

CURENT用戶z12zzzzz即喬布斯

由於喬布斯是繼馬特和Ballu只有他們的鳴叫將顯示

-------------------------------------------- 
Matt (3min ago) 
    Head Pain 
-------------------------------------------- 
Matt (4min ago) 
    Back Pain 
-------------------------------------------- 
Matt (5min ago) 
    Sleepy 
-------------------------------------------- 
Ballu (5min ago) 
    lets Dance 
-------------------------------------------- 

我的問題就在這裏是讓用戶被關注，但不是他們推崇的推文

 var username = window.localStorage.getItem('ls_username'); 
     var Follow = Parse.Object.extend("follow"); 
     var follow = new Parse.Query(Follow); 
     follow.equalTo('followedBy', username); 
     follow.include("following"); 
     follow.include("tweet"); 
     follow.include('tweet.tweetBy'); 
     follow.find().then(function(results){ 
      console.log(results); 
      var contentHtml = ''; 
      for(i in results){ 
       var object = results[i]; 
       // Display individual tweets with their respected usernames 
       // Display only tweets of people being followed by currentuser 
      } 
      $('#globalTweets').html(contentHtml); 
     }); 

Answer 1

我認爲問題是，給定一個用戶，我們如何獲得給定用戶關注的用戶發出的推文？

var _ = require('underscore'); 
// need a user object, not a username, if the relational fields are pointers 
var currentUser = Parse.User.current(); 

// find follows where the user is the follower 
var followQuery = new Parse.query("follow"); // conventional class name would begin with caps 
followQuery.equalTo("followedBy", currentUser); 
followQuery.find().then(function(follows) { 
    // assume underscorejs 
    var followedUsers = _.map(follows, function(f) { 
     return f.get("following"); 
    }); 
    var tweetQuery = new Parse.Query("tweet"); 
    tweetQuery.containedIn("tweetBy", followedUsers); 
    // aggressively fetch the authoring user info 
    tweetQuery.include("tweetBy"); 
    return tweetQuery.find(); 
}).then(function(tweets) { 
    // tweets are tweets by users followed by the given user 
});