index.js

var objectPath = require('object-path');
var deepAssign = require('deep-assign');
var fs = require('file-system');

function JsonBundlerPlugin(options) {
    this.opts = options || {};
    this.omit = this.opts.omit || '';
    this.fileInput = this.opts.fileInput || '';
    this.rootDirectory = this.opts.rootDirectory || '';
    this.localeDirectory = this.opts.localeDirectory || '';

    // concatenate all JSON files for translations
    this.gatherJson = function(compilation) {
        var contents = {};
        fs.recurseSync(this.rootDirectory, [this.fileInput], function(filepath, relative, filename) {
            // watch file for hot reloading
            if (Array.isArray(compilation.fileDependencies)) {
                compilation.fileDependencies.push(filepath);
            } else {
                compilation.fileDependencies.add(filepath);
            }

            // read path and modify for creating JSON
            var localePath = relative.replace(this.omit, '').replace(filename, '');
            localePath = localePath.replace(/^\/|\/$/g, '').replace(/\//g, '.');
            var content = {};
            var data = JSON.parse(fs.readFileSync(filepath, 'utf8'));

            if(localePath) {
                objectPath.set(content, localePath, data);
            } else {
                content = data;
            }
            contents[filename] = contents[filename] || {};
            deepAssign(contents[filename], content);
        }.bind(this));
        return contents;
    }.bind(this);
}

JsonBundlerPlugin.prototype.apply = function(compiler) {
    compiler.hooks.emit.tapAsync("JsonBundlerPlugin", function(compilation, callback) {
      var fullJSON = this.gatherJson(compilation);

      // write each translation locale content in a separate file
      Object
          .keys(fullJSON)
          .map(fileName => {
              var values = deepAssign({}, fullJSON[fileName]);
              compilation.assets[this.localeDirectory + fileName] = {
                  source: function() {
                      return new Buffer(JSON.stringify(values));
                  },
                  size: function() {
                      return Buffer.byteLength(JSON.stringify(values));
                  }
              };
          });
      callback();
    }.bind(this));
};

module.exports = JsonBundlerPlugin;