查找、修改和删除递归嵌入文档猫鼬

Question

>我使用示例中的方案描述。

Comment.add({
    title     : { type: String, index: true }
  , date      : Date
  , body      : String
  , comments  : [Comment]
});
var BlogPost = new Schema({
    title     : { type: String, index: true }
  , slug      : { type: String, lowercase: true, trim: true }
  , date      : Date
  , buf       : Buffer
  , comments  : [Comment]
  , creator   : Schema.ObjectId
});

我在评论中嵌套了几个级别。如何在任何嵌套级别找到正确的注释并对其进行任何操作（删除编辑或添加新的嵌套注释）我试图为搜索进行递归，但您无法保存或删除评论

BlogPost.methods.findComment = function (id, callback) {
  var curentComment = this.comments;
  var findComment = null;
  var recursiveFindComment = function(comment){
      for(i=0;i<comment.length;i++){
          if(findComment){
              break;
          }
          if(comment[i]._id == id){
              findComment  = comment[i];
              break;    
          }else if(comment[i].comments.length>0){
              findComment = recursiveFindComment(comment[i].comments)
          }
      }
      return findComment;
  }
  if(curentComment.id(id)){
     callback(curentComment);  
  }else{
     callback(recursiveFindComment(curentComment, null)) 
  }
}

Answer 1

你可能想看看在MongoDb中使用树（http://www.mongodb.org/display/DOCS/Trees+in+MongoDB）。有许多不同的方法可以帮助解决架构的递归性质。

> t = db.tree
test.tree
> // get entire tree -- we use sort() to make the order nice
> t.find().sort({path:1})
{ "_id" : "a", "path" : "a," }
{ "_id" : "b", "path" : "a,b," }
{ "_id" : "c", "path" : "a,b,c," }
{ "_id" : "d", "path" : "a,b,d," }
{ "_id" : "g", "path" : "a,b,g," }
{ "_id" : "e", "path" : "a,e," }
{ "_id" : "f", "path" : "a,e,f," }
{ "_id" : "g", "path" : "a,b,g," }
> t.ensureIndex( {path:1} )
> // find the node 'b' and all its descendents:
> t.find( { path : /^a,b,/ } )
{ "_id" : "b", "path" : "a,b," }
{ "_id" : "c", "path" : "a,b,c," }
{ "_id" : "d", "path" : "a,b,d," }
{ "_id" : "g", "path" : "a,b,g," }
> // find the node 'b' and its descendents, where path to 'b' is not already known:
> nodeb = t.findOne( { _id : "b" } )
{ "_id" : "b", "path" : "a,b," }
> t.find( { path : new RegExp("^" + nodeb.path) } )
{ "_id" : "b", "path" : "a,b," }
{ "_id" : "c", "path" : "a,b,c," }
{ "_id" : "d", "path" : "a,b,d," }
{ "_id" : "g", "path" : "a,b,g," }