@nofr/core NPM

NoFr: A Compiler for Web Components and PWAs

npm init nofr

NoFr is a simple compiler for generating Web Components and progressive web apps (PWA). NoFr was built by the Family Framework team for its next generation of performant mobile and desktop Web Components.

NoFr combines the best concepts of the most popular frontend frameworks into a compile-time rather than run-time tool. It takes TypeScript, JSX, a tiny virtual DOM layer, efficient one-way data binding, an asynchronous rendering pipeline (similar to React Fiber), and lazy-loading out of the box, and generates 100% standards-based Web Components that run on both modern browsers and legacy browsers back to Internet Explorer 11.

NoFr components are just Web Components, so they work in any major framework or with no framework at all. In many cases, NoFr can be used as a drop in replacement for traditional frontend frameworks given the capabilities now available in the browser, though using it as such is certainly not required.

NoFr also enables a number of key capabilities on top of Web Components, in particular Server Side Rendering (SSR) without the need to run a headless browser, pre-rendering, and objects-as-properties (instead of just strings).

Note: NoFr and Family are completely independent projects. NoFr does not prescribe any specific UI framework, but Family is the largest user of NoFr (today!)

Why NoFr?

NoFr is a new approach to a popular idea: building fast and feature-rich apps in the browser. NoFr was created to take advantage of major new capabilities available natively in the browser, such as Custom Elements v1, enabling developers to ship far less code and build faster apps that are compatible with any and all frameworks.

NoFr is also a solution to organizations and library authors struggling to build reusable components across a diverse spectrum of frontend frameworks, each with their own component system.

Compared to using Custom Elements directly, inside of every NoFr component is an efficient Virtual DOM rendering system, JSX rendering capabilities, asynchronous rendering pipeline (like React Fiber), and more. This makes NoFr components more performant while maintaining full compatibility with plain Custom Elements. Think of NoFr as creating pre-baked Custom Elements as if you wrote in those features yourself.

Getting Started

To create a new project using an interactive cli, run:

npm init nofr

To start developing your new NoFr project, run:

npm start

Creating components

NoFr components are plain ES6/TypeScript classes with some decorator metadata.

Create new components by creating files with a .tsx extension, such as my-component.tsx, and place them in src/components.

import { Component, Prop } from '@nofr/core';

@Component({
  tag: 'my-component',
  styleUrl: 'my-component.css'
})
export class MyComponent {

  @Prop() first: string;

  @Prop() last: string;

  render() {
    return (
      <div>
        Hello, my name is {this.first} {this.last}
      </div>
    );
  }
}

Note: the .tsx extension is required, as this is the standard for TypeScript classes that use JSX.

To use this component, just use it like any other HTML element:

<my-component first="NoFr" last="JS"></my-component>

Naming Components

When creating new component tags, we recommend not using nofr in the component name (ex: <nofr-datepicker>). This is because the generated component has little to nothing to do with NoFr; it's just a web component!

Instead, use a prefix that fits your company or any name for a group of related components.

Hosting the app

NoFr components run directly in the browser through script includes just like normal Custom Elements (because they are just that!), and run by using the tag just like any other HTML component:

Here's an example index.html file that runs a NoFr app:

<!DOCTYPE html>
<html>
<head>
  <title>My App</title>
  <script src="build/app.js"></script>
</head>
<body>
  <my-component first="NoFr" last="JS"></my-component>
</body>
</html>

API

The API for NoFr closely mirrors the API for Custom Elements v1.

Components

Decorator	Description
`@Component()`	Indicate a class is a NoFr component.

`@Prop()`	Creates a property that will exist on the element and be data-bound to this component.
`@State()`	Creates a local state variable that will not be placed on the element.
`@Method()`	Expose specific methods to be publicly accessible.

Why "NoFr?"

A NoFr is a tool artists use for drawing perfect shapes easily. We want NoFr to be a similar tool for web developers: a tool that helps web developers build powerful Web Components and apps that use them, but without creating non-standard runtime requirements.

NoFr is a tool developers use to create Web Components with some powerful features baked in, but it gets out of the way at runtime.

Browser Support

Web Components, specifically Custom Elements, are natively supported in Chrome and Safari and are coming to both Edge and Firefox. A dynamic polyfill loader is already included in order to only load the polyfills for the browsers that are missing specific features.

Chrome (and all Chromium based browsers)
Safari
Edge
Firefox
IE 11

Polyfills

NoFr includes a subset of the core-js polyfills for old browsers like IE11, fetch and conditionally downloads the Custom Elements v1 only when it's needed for modern browsers (EDGE and old versions of Firefox.)

Internet Explorer 11

Browsers that do not support native ESM (at the moment, only IE11 and older) will download a subset of core-js.

This subset is generated using the core-js-builder tool with the following configuration:

require('core-js-builder')({
  targets: 'ie 11',
  modules: [
    'es',
    'web.url',
    'web.url.to-json',
    'web.url-search-params',
    'web.dom-collections.for-each'
  ],
  blacklist: [
    'es.math',
    'es.date',
    'es.symbol',
    'es.array-buffer',
    'es.data-view',
    'es.typed-array',
    'es.reflect',
    'es.promise'
  ]
});

In addition, the following set of polyfills are also included:

Promise
fetch()
CSS variables: We implemented our own CSS variables polyfill that integrates into the NoFrJs runtime.

All browsers

Some modern browsers like Edge do not include native support for Web Components. In that case, we conditionally load the Custom Elements v1 polyfill.

License

web components components nofr family webapp custom elements pwa progressive web app

typescript

1.8.12

2 years ago