Registry / web-framework / polymer-webpack-loader

polymer-webpack-loader

library3.1.0jsnpmunverified

Webpack loader for Polymer (v3 and above) that processes HTML template elements, minifying HTML and including images, fonts, and imported stylesheets in the webpack dependency graph. Version 3.1.0 is the latest, with an active maintenance status. The loader integrates with webpack 2–4 and supports chaining with babel-loader. Differentiator: enables using Polymer 3 components within a webpack build system, handling HTML imports and template optimizations. Alternative to polymer-build or direct HTML imports, it bridges Polymer's component model with webpack's module bundling.

web-framework devops

npm install polymer-webpack-loader

github ↗package ↗

INSTALL

IMPORT

SIG · POLYMER-WEBPACK-LO

polymer-webpack-loader

web-frameworkjavascriptv3.1.0

Install

—

Import

—

Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

polymer-webpack-loader

✓ import polymerWebpackLoader from 'polymer-webpack-loader'

✗ const polymerWebpackLoader = require('polymer-webpack-loader')

ESM default export available; CommonJS require also works. Typically used in webpack config, not in app code.

PolymerWebpackLoader

✓ import { PolymerWebpackLoader } from 'polymer-webpack-loader'

Named export for the loader class; rarely needed directly.

Minimal webpack configuration for processing Polymer HTML components with polymer-webpack-loader.

// webpack.config.js const webpack = require('webpack'); module.exports = { entry: './src/index.js', output: { filename: 'bundle.js', path: __dirname + '/dist' }, module: { rules: [ { test: /\.html$/, use: [ { loader: 'polymer-webpack-loader' } ] } ] } };

Debug

Known issues

deprecatedPolymer 2 branch is deprecated; use version 3.x for Polymer 3.

fix

Upgrade to Polymer 3 and polymer-webpack-loader 3.x.

affects: >=1.0 <3.0

gotchaWebcomponent polyfills must be loaded in specific order to avoid 'Failed to construct HTMLElement' errors.

fix

Use the demo index.ejs ordering: polyfills before main bundle.

affects: >=3.0

breakingWebpack 5 support not officially added; may require adjustments.

fix

Use webpack 4 or consider alternatives like @polymer/webpack-loader for webpack 5.

affects: >=3.0

gotchaHTML-loader options passed via htmlLoader must be compatible with the installed html-loader version.

fix

Check html-loader documentation and ensure options are correct.

affects: >=3.0

Errors

Common errors & fixes

Uncaught TypeError: Failed to construct 'HTMLElement': Please use the 'new' operator, this DOM object constructor cannot be called as a function.

Web component polyfills loaded out of order or missing.

fix

Load polyfills in correct sequence before main bundle (see demo/src/index.ejs).

Module parse failed: Unexpected token (1:0) You may need an appropriate loader to handle this file type.

polymer-webpack-loader not applied to .html files.

fix

Add the loader rule for test: /\.html$/ in webpack config.

Error: Polymer entry point must be an HTML file.

Entry point is a JS file instead of HTML.

fix

Set entry to an HTML file that imports components.

Upgrade

Version history

3.1.0latest on npm

Audit

Dependencies

webpackrequiredpeer dependency for webpack loader integration

Agent activity

2 hits · last 30 days

node

Resources

githubhttps://github.com/webpack-contrib/polymer-webpack-loader ↗

packagehttps://www.npmjs.com/package/polymer-webpack-loader ↗