Directory name revisioning through content hashing

Getting Started

If you haven't used grunt before, be sure to check out the Getting Started guide.

From the same directory as your project's Gruntfile and package.json, install this plugin with the following command:

npm install grunt-revdir --save-dev

Once that's done, add this line to your project's Gruntfile:

grunt.loadNpmTasks('grunt-revdir');

If the plugin has been installed correctly, running grunt --help at the command line should list the newly-installed plugin's task or tasks. In addition, the plugin should be listed in package.json as a devDependency, which ensures that it will be installed whenever the npm install command is run.

The "revdir" task

Use the revdir task to prepend a revision hash to a directory name according to its contents (the contents of its containing files).

Overview

In your project's Gruntfile, add a section named revdir to the data object passed into grunt.initConfig().

grunt.initConfig({
  revdir: {
    options: {
      encoding: 'utf8',
      algorithm: 'md5',
      length: 8,
      exclude: ['*.gif']
    },
    assets: {
      files: [{
        src: [
          'img/',
          'fonts/'
        ]
      }]
    }
  },
})

Options

options.encoding

Type: String Default value: 'utf8'

The encoding of the file contents.

options.algorithm

Type: String Default value: 'md5'

algorithm is dependent on the available algorithms supported by the version of OpenSSL on the platform. Examples are 'sha1', 'md5', 'sha256', 'sha512', etc. On recent releases, openssl list-message-digest-algorithms will display the available digest algorithms.

options.length

Type: Number Default value: 8

The number of characters of the file content hash to prefix the file name with.

options.exclude

Type: Array Default value: []

List of files/folders to exclude from md5 content hashing.

options.overwrite

Type: boolean Default value: true

When dest is not provided, whether to overwrite src with hashed name (true) or create a copy (false).

Usage Example

Basic Asset Revving

This will rename scripts and css with an 8 character long hash prefix. For example 9becff3a-scripts and ae35dd05-css. The hash value depends on the directory's containing file's contents.

grunt.initConfig({
  rev: {
    files: {
      src: ['scripts', 'css']
    }
  }
})

Custom Options

Change the algorithm or length to style the generated asset file names. Specify a destination to put the hash-named copy of the directory.

grunt.initConfig({
  rev: {
    options: {
      algorithm: 'sha1',
      length: 4
    },
    files: {
      src: ['scripts'],
      dest: 'build'
    }
  }
})