通过数组上的推送操作和对象上的设置操作进行mongoose更新

I have this mongoose schema

我有这个猫鼬模式

var ContactSchema = module.exports = new mongoose.Schema({
  name: {
    type: String,
    required: true
  },
  phone: {
    type: Number,
    required: true,
  },
  messages: [
  {
    title: {type: String, required: true},
    msg: {type: String, required: true}
  }],
  address:{ city:String,
            state:String
  }
});
var Co