在Express 3中关闭数据库连接

Question

在Express 3中,当进程存在时,如何处理关闭数据库连接？

.on('close', ...除非您明确使用HTTP服务器的.close()调用,否则不会发出该事件.

到目前为止,这是我最接近的,但它使用process.on而不是server.on:

process.on('SIGTERM', function () {
   // Close connections.
   process.exit(0);
});

Answer 1

基于以下信息:

• https://github.com/visionmedia/express/issues/1366
• http://blog.argteam.com/coding/hardening-node-js-for-production-part-3-zero-downtime-deployments-with-nginx/

-

var express = require('express');

var app = express();
var server = app.listen(1337);
var shutting_down = false;

app.use(function (req, resp, next) {
 if(!shutting_down)
   return next();

 resp.setHeader('Connection', "close");
 resp.send(503, "Server is in the process of restarting");
 // Change the response to something your client is expecting:
 //   html, text, json, etc.
});

function cleanup () {
  shutting_down = true;
  server.close( function () {
    console.log( "Closed out remaining connections.");
    // Close db connections, other chores, etc.
    process.exit();
  });

  setTimeout( function () {
   console.error("Could not close connections in time, forcing shut down");
   process.exit(1);
  }, 30*1000);

}

process.on('SIGINT', cleanup);
process.on('SIGTERM', cleanup);

该Connection: close头被用来告诉任何keep-alive连接关闭接下来他们发送一个HTTP请求的时间.更多信息:http://www.jmarshall.com/easy/http/#http1.1s4

我不知道是否有其他方法可以关闭keep-alive连接.除非keep-alive关闭连接,否则节点进程将挂起.默认空闲超时为2分钟.更多信息.node.js keep-alive超时(包括更改超时):如何在nodejs服务器中设置HTTP Keep-Alive超时