Polymer App Toolbox - Starter Kit Plus

Up-to-date fork of Polymer Starter Kit. Only Polymer 2.0+

This template is a starting point for building apps using a drawer-based layout. The layout is provided by app-layout elements.

This template, along with the polymer-cli toolchain, also demonstrates use of the "PRPL pattern" This pattern allows fast first delivery and interaction with the content at the initial route requested by the user, along with fast subsequent navigation by pre-caching the remaining components required by the app and progressively loading them on-demand as the user navigates through the app.

The PRPL pattern, in a nutshell:

• Push components required for the initial route
• Render initial route ASAP
• Pre-cache components for remaining routes
• Lazy-load and progressively upgrade next routes on-demand

New Features 🎉

• yarn build using Polymer Build and Gulp.
• yarn format:css using js-beautify.
• yarn format:html using js-beautify.
• yarn format:js using eslint, Prettier and eslint-config-google.
• yarn format:json using Prettier.
• yarn json5 for convert JSON5 files to strict JSON.
• yarn lint:css using stylelint and stylelint-config-standard.
• yarn lint:html using htmllint.
• yarn lint:js using eslint, Prettier and eslint-config-google.
• yarn lint:json using Prettier.
• yarn min:img for minify PNG, JPEG, GIF and SVG images and convert to WebP format using imagemin and imagemin-webp.
• Run linters and formatters on git staged files using lint-staged.

TODO

• Browsersync for keeping multiple browsers & devices in sync when building websites.
• Reshape for transforming HTML with JavaScript plugins.
• gulp-rev-all for static asset revisioning with dependency considerations, appends content hash to each filename, re-writes references.
• Lighthouse for auditing, performance metrics, and best practices.
• and other issues ...

Quickstart

We've recorded a Polycast to get you up and running with PSK2 fast!

Setup

Prerequisites

First, install Polymer CLI using npm (we assume you have pre-installed node.js).

yarn global add polymer-cli

Then, install generator-polymer-init-starter-kit-plus.

yarn global add generator-polymer-init-starter-kit-plus

Initialize project from template

mkdir my-app
cd my-app
polymer init starter-kit-plus

Start the development server

This command serves the app at http://localhost:8080 and provides basic URL routing for the app:

polymer serve --open

Build

This command performs HTML, CSS, and JS minification on the application dependencies, and generates a service-worker.js file with code to pre-cache the dependencies based on the entrypoint and fragments specified in polymer.json. The minified files are output to the build/unbundled folder, and are suitable for serving from a HTTP/2+Push compatible server.

In addition the command also creates a fallback build/bundled folder, generated using fragment bundling, suitable for serving from non H2/push-compatible servers or to clients that do not support H2/Push.

polymer build

Preview the build

This command serves the minified version of the app at http://localhost:8080 in an unbundled state, as it would be served by a push-compatible server:

polymer serve build/unbundled

This command serves the minified version of the app at http://localhost:8080 generated using fragment bundling:

polymer serve build/bundled

Run tests

This command will run Web Component Tester against the browsers currently installed on your machine:

polymer test

If running Windows you will need to set the following environment variables:

• LAUNCHPAD_BROWSERS
• LAUNCHPAD_CHROME

Read More here daffl/launchpad

Adding a new view

You can extend the app by adding more views that will be demand-loaded e.g. based on the route, or to progressively render non-critical sections of the application. Each new demand-loaded fragment should be added to the list of fragments in the included polymer.json file. This will ensure those components and their dependencies are added to the list of pre-cached components and will be included in the bundled build.