dom-middleware

Sure, you have templates and generate HTML, but sometimes you just need one more tweak on your pages before they go out the server. dom-middleware to the rescue.

Go!

npm install dom-middleware

var path = require('path');
var express = require('express');
var dom = require('dom-middleware')();
dom.jquery = true;
var app = express()
    .use(dom
      .use(function (window, next) {
        window.$('title').text('Oh yeah!');
        next();
      })
    )
    .use(express.static()
    .listen(9999);

This is middleware-middleware, it creates a substream of middleware that works on a DOM as a response instead of a raw text stream. This allows you to do complex transformations on the server using client side technique. When you are all done, the resulting window.document is sent out the response as html.

This has some overhead, you should benchmark yourself to see.

Notes

It's about that simple, note that this is using jsdom, combined with middleware. The 'trick' that makes it work is in intercepting write and end for response objects when the content type is text/html. The approach is:

• detect a header set of text/html
• substitute write and end with a buffering version
• on end, build up a DOM and hand it to your functions

Becuase this is hooking response, you will likely need to put it high in your middleware chain. Like first.