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Assets to map

A plugin for webpack

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Main goal

Extract bundle(s) generated by webpack and add it in a file JSON or YAML or TOML.

What for?

Originally we used it on a Hugo.io project: we needed to inline in a template style and script generated by Webpack. To do so, we decided to go through /Data repertory to access it with Hugo environment variables .Data.

How to use?


$ npm install --save-dev assets-to-map-webpack-plugin
$ yarn add -D assets-to-map-webpack-plugin


module.exports = {
    // more webpack config
    plugins: [
        new AssetsToMap({
            // options


  • sourcePath - {String} (default: "")
    Where to find the assets you need to put in the Json file
  • outputPath - {String} (default: "")
    Where to generate the json file
  • filename - {String} (default: "")
    Name of the destination file. Don't specify the extension.
  • format - {String} (default: "json")
    Possible values:
    • "json"
    • "toml"
    • "yaml" (The format will also defines the extension of the output file)
  • files - {Object} required
    Example: {key: "name"}
    • key will be used as the key in the generated json file
    • name is the name of the bundle you're appending to the generated json file.
  • deleteFiles - {Bool} (default: false)
    allows the plugin to delete source files inlined if true
  • verbose - {Bool} (default: false)


The example below will create a file ./site/data/assets.json containing two keys: css (from the file generated by ExtractTextPlugin) and js, both located in ./site/static. tracking.js will not be included in assets.json for it's not declared in the files option.

const webpack = require("webpack");
const ExtractTextPlugin = require("extract-text-webpack-plugin");
+const AssetsToMap = require('assets-to-map-webpack-plugin');

module.exports = {
    entry: {
        main: [
        tracking: "./assets/js/tracking.js",
    output: {
        path: path.join(__dirname, "site/static"),
        filename: "[name].js"
    module: {
        loaders: [
            // ...
    plugins: [
        new ExtractTextPlugin("[name].css"),
        // JS optimizations like
        // new UglifyJSPlugin(),
+        new AssetsToMap({
+            sourcePath: "site/static/",
+            outputPath: "site/data/",
+            filename: "assets",
+            files: {
+                css: "main.css",
+                js: "main.js"
+            }
+        }),

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