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fly-rev Build status npm package

Prepare front-end assets for cache-busting / versioning / hashing.

This plugin includes three functions:

  1. rev(): Rename files by appending a unique hash, based on contents.
  2. revManifest(): Create a manifest that maps old filenames to newly versioned filenames. (optional)
  3. revReplace(): Update all references to versioned files. (optional)

Make sure to set the files to never expire for this to have an effect.


npm install --save-dev fly-rev


The rev() task is the core method; thus is required for anything to occur.

Both revManifest() and revReplace() are optional plugins.

exports.default = function * (fly) {
  yield fly.source('app/**/*')
      ignores: ['.html', '.jpg', '.png']
      dest: 'dist',
      file: 'manifest.json',
      trim: str => str.replace(/app\/client/i, 'assets')
      ignores: ['.php']



Generate a unique hash (based on a file's contents) and append it to the filename.

//=> bundle-{hash}.js 
//=> bundle-{hash}.min.js 

Any files that are processed will receive two new keys: orig and hash. In addition, the base key will be updated with the new, versioned filename.


Type: array
Default: ['.png', 'jpg', '.jpeg', '.svg', '.gif', '.woff', '.ttf', '.eot']

A list of file extensions that should NOT be renamed/processed.


Create a manifest file that relates old filenames to versioned counterparts.


Type: string
Default: 'rev-manifest.json'

The name of the manifest file to be created.


Type: string
Default: fly.root

The directory where your manifest file should be created. Defaults to Fly's root directory (where flyfile.js is found).


Type: boolean
Default: true

Whether or not the manifest's contents should be sorted alphabetically. (Does not add any performance / usage benefits.)


Type: string or function
Default: .

Edit the final keys & values within the manifest. If string, the value will be resolved relative to Fly's root directory. Using a function provides more fine-tuned control.

yield fly.source('app/client/*.js').rev()
  .revManifest({trim: 'app'}).target('dist');
  //=> "client/demo.js": "client/demo-1abd624s.js" 
yield fly.source('app/client/*.js').rev()
    trim: str => str.replace(/app\/client/i, 'assets')
  //=> "assets/demo.js": "assets/demo-1abd624s.js" 


Update references to all versioned files within a given source.

Matching files from within fly.source() are available for inspection & modifications. Because of this, it is recommended that all your rev-* usage is extracted to a separate, production-only task whose source includes all development files.


Type: array
Default: ['.png', 'jpg', '.jpeg', '.svg', '.gif', '.woff', '.ttf', '.eot']

A list of file extensions whose content should not be updated.


MIT © Luke Edwards