index.js

'use strict'

var fs = require('fs')
var path = require('path')
var staticMapKey = require('static-file-loader').key

function StaticFilesWebpackPlugin (options) {
  options = options || {}

  var outputPath = options.outputPath || 'static.json'
  if (!path.isAbsolute(outputPath)) {
    outputPath = path.join(process.cwd(), outputPath)
  }

  this.options = {
    outputPath: outputPath,
    useRelativePaths: options.useRelativePaths,
    prefix: options.prefix,
    replace: options.replace || function (processedPath) { return processedPath }
  }
}

StaticFilesWebpackPlugin.prototype.apply = function (compiler) {
  compiler.plugin('after-emit', function (compilation, callback) {
    var map = compilation[staticMapKey] || {}
    if (this.options.useRelativePaths) {
      var relativePathBase
      if (typeof this.options.useRelativePaths === 'string') {
        relativePathBase = this.options.useRelativePaths
        if (!path.isAbsolute(relativePathBase)) {
          relativePathBase = path.join(process.cwd(), relativePathBase)
        }
      } else {
        relativePathBase = process.cwd()
      }

      var replace = this.options.replace
      var prefix = this.options.prefix ? this.options.prefix + path.sep : ''
      map = Object.keys(map).reduce(function (mapAcc, filePath) {
        var relativePath = filePath.replace(relativePathBase + path.sep, prefix)
        relativePath = replace(relativePath)
        mapAcc[relativePath] = map[filePath]
        return mapAcc
      }, {})
    }

    // Ensure that the keys in the map are sorted
    map = Object.keys(map).sort().reduce(function (mapAcc, filePath) {
      mapAcc[filePath] = map[filePath]
      return mapAcc
    }, {})

    fs.writeFile(this.options.outputPath, JSON.stringify(map), function (err) {
      if (err) throw err
      callback()
    })
  }.bind(this))
}

module.exports = StaticFilesWebpackPlugin