nodejs向mongodb中插入數(shù)據(jù)報(bào)錯(cuò)Unknown modifier: $pushAll

schemas

var CommentSchema = new mongoose.Schema({
    movie: {type: ObjectId, ref: "Movie"},
    from: {type: ObjectId, ref: "User"},
    reply: [{
        from: {type: ObjectId, ref: "User"},
        to: {type: ObjectId, ref: "User"},
        content: String
    }],
    content: String,
    meta: {
        createAt: {
            type: Date,
            default: Date.now()
        },
        updateAt: {
            type: Date,
            default: Date.now()
        }

    }
})

controllers

    if(_comment.cid){
        Comment.findById(_comment.cid, function(err, comment){
            console.log(comment)
            var reply = {
                from: _comment.from,
                to: _comment.tid,
                content: _comment.content
            }

            //console.log(comment instanceof Array); // false
            comment.reply.push(reply);
            comment.save(function(err, movie){
                if(err){
                    //console.log('abc')
                    console.log(err);
                }
                res.redirect('/movie/' + movieId);
            })
        })
    }

這是一個(gè)評(píng)論模塊，if中實(shí)現(xiàn)的邏輯是對(duì)當(dāng)前的評(píng)論進(jìn)行回復(fù)，save直接拋出錯(cuò)誤Unknown modifier: $pushAll，請(qǐng)問(wèn)是哪個(gè)環(huán)節(jié)出了問(wèn)題，是不是push的數(shù)據(jù)類型不正確導(dǎo)致？還是其他原因，怎么修改？