# cache-bust
Use cache busting in express. Adds a version query string to ressources.
## Usage with express
```js
var express = require('express');
var cacheBust = require('cache-busted');
var app = express();
cacheBust.handler(app);
```
This exposes the function cacheBust in your app locals. Enabling you to do the following (example using jade):
```jade
head
title Hello World
!= cacheBust('/public/js/app.js')
!= cacheBust('/public/css/style.css')
!= cacheBust('/public/css/style', 'css')
```
Output:
```html
Hello World
```
## Options
Add the options to the `handler` call: `cacheBust.handler(app, options)`
`version`: Use this exact version. Default: null which will make this module look for a package.json in the folder below
`packageLocation`: Path to the `package.json`. Defaults to `../../package.json`.
## Difference production and development
The above example is the output if the NODE_ENV environment variable is set to `production` or `integration`. Otherwise it also appends the current timestamp so that each request will load all new dependencies. Example:
```html
```