text: const mongoose = require('mongoose');
  //链接mongo,并且使用imooc这个集合
  const DB_URL = 'mongodb://localhost:27017/imooc-chat'
  mongoose.connect(DB_URL)
  
  const models={
      user:{
          'user':{'type':String,'require':true},
          'pwd':{'type':String,'require':true},
          'type':{'type':String,'require':true},
          //头像
          'avatar':{'type':String},
          //简介
          'desc':{'type':String},
          //职位
          'title':{'type':String},
          'company':{'type':String},
          'money':{'type':String}
      },
      chat:{
          'chatid':{'type':String,'require':true},
          'from':{'type':String,'require':true},
          'to':{'type':String,'require':true},
          'read':{'type':Boolean,'default':false},
          'content':{'type':String,'require':true,'default':''},
          'create_time':{'type':Number,'default':new Date().getTime()}
      }
  }
  
  for(let  m in models){
      mongoose.model(m,new mongoose.Schema(models[m]))
  }
  
  module.exports={
      getModel:function(name){
          return mongoose.model(name)
      }
  }