metalsmith-contenthash

based off of metalsmith-fingerprint-ignore, uses crypto.createHash instead of crypto.createHmac

Installation

npm install metalsmith-contenthash

Example (serving assets)

var Metalsmith = require('metalsmith');
var assets = require('metalsmith-assets');
var contenthash = require('metalsmith-contenthash');
 
var ms = Metalsmith(process.cwd());
 
 
ms.use(assets({
    source: './assets',
    destination: './assets',
}));
 
 
// no options are required, these are the defaults
//  i.e.  same as:  ms.use(contenthash())  or  ms.use(contenthash({}))
ms.use(contenthash({
    
    // don't keep orignal untagged file
    keep: false,
    
    // use sha256 for hashing
    algorithm: 'sha256',
    
    // match static files
    // uses multimatch  https://www.npmjs.com/package/multimatch
    pattern: ['**/*.{js,scss,css,map,png,jpg}'],
    
    // function for determining new filename
    // default function uses only first 16 hexadecimal digits
    rename: function(filepath, digest) {
        
        // we split at the first period, instead of extname
        //  this is to handle .css.map
        var ext = filepath.indexOf('.');
        
        return [
            filepath.substring(0, ext),
            '.', digest.substr(0, 16),
            filepath.substring(ext),
        ].join('');
        
    },
    
}));
 
 
ms.build(function(error) {
    if (error) throw error;
    
    console.log('Built');
});
 

The new filenames are accessible via the hashes metadata object.

<link href="{{ hashes.[assets/css/main.js] }}" rel="stylesheet" type="text/css" />
<script src="{{ hashes.[assets/js/main.js] }}"></script>
<img src="{{ hashes.[assets/img/headers/IMG_2083.jpg] }}">