how to properly close node-express server?

Question

I need to close server after getting callback from /auth/github/callback url. With usual HTTP API closing server is currently supporting with s

Answer 1

If any error occurs in your express app then you must have to close the server and you can do that like below-

var app = express();
var server = app.listen(process.env.PORT || 5000)

If any error occurs then our application will get a signal named SIGTERM

You can read more about node signal here-

https://www.gnu.org/software/libc/manual/html_node/Termination-Signals.html

process.on('SIGTERM', () => {
  console.info('SIGTERM signal received.');
  console.log('Closing http server.');
  server.close(() => {
    console.log('Http server closed.');
  });
});

Answer 2

In express v3 they removed this function.

You can still achieve the same by assigning the result of app.listen() function and apply close on it:

var server = app.listen(3000);
server.close()

https://github.com/visionmedia/express/issues/1366

Answer 3

app.listen() returns http.Server. You should invoke close() on that instance and not on app instance.

Ex.

app.get(
    '/auth/github/callback',
    passport.authenticate('github', { failureRedirect: '/login' }),
    function(req, res) {
        res.redirect('/');

        setTimeout(function () {
            server.close();
            // ^^^^^^^^^^^
        }, 3000)
    }
);

var server = app.listen('http://localhost:5000/');

You can inspect sources: /node_modules/express/lib/application.js

Answer 4

I have answered a variation of "how to terminate a HTTP server" many times on different node.js support channels. Unfortunately, I couldn't recommend any of the existing libraries because they are lacking in one or another way. I have since put together a package that (I believe) is handling all the cases expected of graceful express.js HTTP(S) server termination.

https://github.com/gajus/http-terminator

The main benefit of http-terminator is that:

• it does not monkey-patch Node.js API
• it immediately destroys all sockets without an attached HTTP request
• it allows graceful timeout to sockets with ongoing HTTP requests
• it properly handles HTTPS connections
• it informs connections using keep-alive that server is shutting down by setting a connection: close header
• it does not terminate the Node.js process