express-webpack-assets

0.1.0 verified Sat Apr 25 auth: no javascript maintenance

Express middleware that loads hashed Webpack asset manifests generated by assets-webpack-plugin, exposing asset paths (JS, CSS, etc.) to templates via a `webpack_asset()` helper. Version 0.1.0 is the latest stable release. It supports single or multiple JSON manifest files (merged in filesystem order). Useful for referencing versioned assets without hardcoding hashes. Not actively maintained; alternatives include webpack-manifest-plugin with express middleware.

Common errors

error Cannot read property 'js' of undefined ↓

cause The asset key or file type does not exist in the loaded manifest JSON.

fix

Verify the manifest file contains the expected asset keys (e.g., 'one') and file types (e.g., 'js').

error Error: ENOENT: no such file or directory, open './config/webpack-assets.json' ↓

cause The path provided to the middleware does not point to an existing file or directory.

fix

Ensure the path is correct relative to the project root or use an absolute path.

error webpack_asset is not defined ↓

cause The middleware did not run before the template rendering, or the path is invalid causing the helper not to be injected.

fix

Ensure app.use(webpackAssets(...)) is placed before any route handlers that render templates.

error TypeError: webpackAssets is not a function ↓

cause Importing the module incorrectly (e.g., using named import instead of default import).

fix

Use import webpackAssets from 'express-webpack-assets' or const webpackAssets = require('express-webpack-assets').default in CommonJS.

Warnings

gotcha When passing a directory path, the order of merging JSON files is determined by filesystem read order (not alphabetical), which can cause unexpected overrides. ↓

fix Use a single JSON file or ensure unique property names across files.

gotcha The `webpack_asset` helper is attached as a local variable to Express `res.locals`, so it is only available in templates that are rendered from the same response context. ↓

fix Access the helper only within templates rendered after the middleware runs.

deprecated The package is no longer actively maintained; consider using webpack-manifest-plugin with a custom Express middleware. ↓

fix Migrate to a more modern asset management solution.

Install

npm install express-webpack-assets

yarn add express-webpack-assets

pnpm add express-webpack-assets

Imports

default

wrong

const webpackAssets = require('express-webpack-assets')

correct

import webpackAssets from 'express-webpack-assets'

ESM import works as the module has a default export.

webpack_asset

wrong

Using webpack_assets (plural) instead of webpack_asset (singular)

correct

<!-- Available in template locals after middleware is applied: webpack_asset('one', 'js') -->

The helper is injected as a local variable named 'webpack_asset'.

options

wrong

app.use(webpackAssets({ path: './config/webpack-assets.json' }))

correct

app.use(webpackAssets('./config/webpack-assets.json', { devMode: false }))

The first argument is a path string, not an options object.

Quickstart

Sets up Express middleware to load a webpack assets JSON file and expose the `webpack_asset` helper in templates.

import express from 'express';
import webpackAssets from 'express-webpack-assets';

const app = express();
app.set('view engine', 'ejs');
// Load asset manifest and inject webpack_asset helper into res.locals
app.use(webpackAssets('./config/webpack-assets.json', { devMode: false }));

app.get('/', (req, res) => {
  // In the EJS template, use: <script src="<%= webpack_asset('one', 'js') %>"></script>
  res.render('index');
});

app.listen(3000);