我是新手.我正在尝试加入不同的集合来获取一些数据.我能够获得帖子创建者和喜欢的信息,但是我如何使用mongoose中的关联获得他们的评论和评论者信息的帖子? 用户架构 const userSche
          用户架构
const userSchema = mongoose.Schema({
     username: {
         type: String,
         minlength: [6, 'Minimum length of username must be 6 characters'],
         trim: true,
         lowercase: true,
         required: true,
         unique: true
     },
     email: {
         type: String,
         minlength: [6, 'Minimum length of email must be 6 characters'],
         trim: true,
         unique: true
     },
     password: {
         type: String,
         minlength: [6, 'Minimum length of password must be 6 characters'],
         required: true
     },
     tokens: [{
         access: {
             type: String
         },
         token: {
             type: String
         }
     }],
     posts: [{
         type: mongoose.Schema.Types.ObjectId,
         ref: 'post'
     }]
 }, {
     timestamps: true
 }); 
 POST架构
const postSchema = mongoose.Schema({
     title: {
         type: String,
         trim: true,
         required: true
     },
     body: {
         type: String,
         trim: true,
         required: true
     },
     _creator: {
         type: ObjectId,
         ref: 'user'
     },
     comments: [{
         type: ObjectId,
         ref: 'comment'
     }],
     likes: [{
         type: mongoose.Schema.Types.ObjectId,
         ref: 'user'
     }]
 }, {
     timestamps: true
 }); 
 评论架构
const commentSchema = mongoose.Schema({
     title: {
         type: String,
         trim: true
     },
     _creator: {
         type: ObjectId,
         ref: 'user'
     },
     _post: {
         type: ObjectId,
         ref: 'post'
     }
 }, {
     timestamps: true
 });
 // get posts from all users
 postRoutes.get('/', authMiddleware, async(req, res) => {
     try {
         const user = req.user;
         const posts = await Post.find({})
             .populate('_creator likes comments')
             .sort({
                 createdAt: -1
             })
             .limit(1);
         return res.send(posts);
     } catch (e) {
         return res.status(400).send(e);
     }
 }); 
 我只收到评论ID,但我希望评论他们的信息.我究竟做错了什么?
json_object_image
这是docs http://mongoosejs.com/docs/populate.html的链接
