node.js - 如果 mongodb 已启动并重新建立连接，则 express app 侦听

Question

我有这段代码可以打开与 mongodb 的连接：

db_connect_mongo = init: (callback) ->
  self = this
  mongo_options = db:
      safe: true
  mongoose.connect DB_URL, mongo_options
  db = self.db_mongo = mongoose.connection

  db.on "error", (error) ->
    logger.error "ERROR connecting to: " + DB_URL, logCategory
    callback error, null

  db.on "connected", ->
    logger.info "SUCCESSFULLY connected to: " + DB_URL, logCategory
    callback true, db

  db.on "disconnected", ->
    logger.info "DISCONNECTED from the database: " + DB_URL, logCategory

# check and connect to Redis

exports = module.exports = db_connect_mongo

然后我在我的 app.coffee 中调用它，例如：

#Connect to database
dbconnection = require "./utils/dbconnect"
dbconnection.init (result) ->
  logger.info "Database initialized: " + result, logCategory

当我关闭 mongo db 时，我info: [DATABASE Connection] DISCONNECTED from the database: mongodb://127.0.0.1:27017/zmgc-mongo在 logger.coffee 中得到一个 so，如果 mongodb 出现，我想“监听”以便建立连接。

什么是捕获所有取消/重新连接到数据库的事件的好方法？