Polymer App Toolbox - Starter Kit

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

Migrating from Polymer Starter Kit v1?

Check out our blog post that covers what's changed in PSK2 and how to migrate!

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).

npm install -g polymer-cli

Second, install Bower using npm

npm install -g bower

Initialize project from template

mkdir my-app
cd my-app
polymer init polymer-2-starter-kit

Start the development server

This command serves the app at http://127.0.0.1:8081 and provides basic URL routing for the app:

polymer serve

Build

The polymer build command builds your Polymer application for production, using build configuration options provided by the command line or in your project's polymer.json file.

You can configure your polymer.json file to create multiple builds. This is necessary if you will be serving different builds optimized for different browsers. You can define your own named builds, or use presets. See the documentation on building your project for production for more information.

The Polymer Starter Kit is configured to create three builds using the three supported presets:

"builds": [
  {
    "preset": "es5-bundled"
  },
  {
    "preset": "es6-bundled"
  },
  {
    "preset": "es6-unbundled"
  }
]

Builds will be output to a subdirectory under the build/ directory as follows:

build/
  es5-bundled/
  es6-bundled/
  es6-unbundled/

es5-bundled is a bundled, minified build with a service worker. ES6 code is compiled to ES5 for compatibility with older browsers.
es6-bundled is a bundled, minified build with a service worker. ES6 code is served as-is. This build is for browsers that can handle ES6 code - see building your project for production for a list.
es6-unbundled is an unbundled, minified build with a service worker. ES6 code is served as-is. This build is for browsers that support HTTP/2 push.

Run polymer help build for the full list of available options and optimizations. Also, see the documentation on the polymer.json specification and building your Polymer application for production.

Preview the build

This command serves your app. Replace build-folder-name with the folder name of the build you want to serve.

polymer serve build/build-folder-name/

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

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 build.