grunt-preload-manifest

Creates manifest files that can be used by preloaders such as PreloadJS.

Getting Started

This plugin requires Grunt ~0.4.2

If you haven't used Grunt before, be sure to check out the Getting Started guide, as it explains how to create a Gruntfile as well as install and use Grunt plugins. Once you're familiar with that process, you may install this plugin with this command:

npm install grunt-preload-manifest --save-dev

Once the plugin has been installed, it may be enabled inside your Gruntfile with this line of JavaScript:

grunt.loadNpmTasks('grunt-preload-manifest');

The "manifest" task

Overview

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

grunt.initConfig({
  manifest: {
    options: {
      // Task-specific options go here.
    },
    your_target: {
      // Target-specific file lists and/or options go here.
    },
  },
});

Options

options.root

Type: String Default value: null

The base path that is shared by all assets URLs in the manifest. This reduces the file size of the manifest by eliminating the need to prefix the URL for each asset. Remember to include a trailing / at the end of this path.

options.priorities

Type: Array Default value: []

A list of asset URLs that should come first in the manifest. This will ensure those assets are preloaded as soon as possible. These URLs are relative to the root URL just like the other assets in the manifest.

options.indent

Type: Integer or String Default value: 4

Controls the indentation of the JSON data in the manifest. An integer will indent by that number of spaces, a string will indent using that string, and null will result in no indentation.

Usage Examples

Example Manifest

{
    "manifest": [
        "primary/first.jpg",
        "primary/junk.txt",
        "primary/second.png",
        "secondary/a.ttf",
        "secondary/b.svg",
        "secondary/c.eot",
    ],
    "path": "static/assets/"
}

Default Options

The default options are used to add all files within the app/static directory to the manifest. Be sure to include the filter: isFile to prevent directories from being added.

grunt.initConfig({
  manifest: {
    options: {},
    files: [
      {
        cwd: 'app/static',
        src: ['**/*'],
        dest: 'app/preload_manifest.json',
        filter: 'isFile'
      }
    ],
  },
});

Images only

Globbing patterns are used to only add images within the app/static directory to the manifest.

grunt.initConfig({
  manifest: {
    options: {},
    files: [
      {
        cwd: 'app/static',
        src: ['**/*.{jpg,jpeg,gif,png}'],
        dest: 'app/preload_manifest.json',
        filter: 'isFile'
      }
    ],
  },
});

Root Option

The root option is used add a path URL to the manifest, eliminating the need to prefix all asset URLs with said root URL.

grunt.initConfig({
  manifest: {
    options: {
      root: 'static/assets/'
    },
    files: [
      {
        cwd: 'app/static',
        src: ['**/*.{jpg,jpeg,gif,png}'],
        dest: 'app/preload_manifest.json',
        filter: 'isFile'
      }
    ],
  },
});

Priorities Option

The priorities option is used to ensure certain assets are loaded first.

grunt.initConfig({
  manifest: {
    options: {
      root: 'static/assets/'
      priorities: ['images/logo.jpg', 'images/background.jpg']
    },
    files: [
      {
        cwd: 'app/static',
        src: ['**/*.{jpg,jpeg,gif,png}'],
        dest: 'app/preload_manifest.json',
        filter: 'isFile'
      }
    ],
  },
});

Contributing

In lieu of a formal styleguide, take care to maintain the existing coding style. Add unit tests for any new or changed functionality. Lint and test your code using Grunt.

Release History

0.1.5 - root is now path in manifest, as per specification 0.1.0 - Initial release