react-wormhole-hoc

A better alternative to react context.

Motivations

Context is a very powerful feature in React, but it may get you into trouble sometimes.

See these issues for detail:

• https://medium.com/@mweststrate/how-to-safely-use-react-context-b7e343eff076
• https://github.com/facebook/react/issues/2517

Features

• Works well with shouldComponentUpdate and React.PureComponent
• No namespace conflict
• Works well outside React Component
• Can communicate without parent-child relationship

Quick Start

import React, { Component, PropTypes } from 'react';
import Wormhole from 'react-wormhole-hoc';

const storeWormhole = new Wormhole({ content: '...' })

const fetchData = () => new Promise((resolve) =>
	setTimeout(() => resolve({ content: 'awesome!!1' }), 1000)
);

@storeWormhole.hoc('myStore')
class DeepChild extends Component {
	static propTypes = {
		myStore: PropTypes.object,
	};

	render() {
		return (
			<div>
				content: {this.props.myStore.content}
			</div>
		);
	}
}

class NoUpdate extends Component {
	shouldComponentUpdate() {

		// no update
		return false;
	}

	render() {
		return (
			<DeepChild />
		);
	}
}

class App extends Component {
	componentDidMount() {
		fetchData('/fake/api').then((store) => {
			storeWormhole.set(store);
		});
	}
	render() {
		return (
			<NoUpdate />
		);
	}
}

For more usage, please check the ./example directory, or clone this repo and run npm run example to start live demo.

API

• constructor
• get
• set
• on
• once
• off
• hoc
• static connect
• static Provider

constructor(initialValue)

Create wormhole instance.

Arguments

1. initialValue (Any): Initial value.

Return

(Wormhole): wormhole instance.

get()

Get current value. Will emit an get event.

Return

(Any): Value.

set(newValue)

Set new value. Will emit an set event. If the newValue is different with the old value, it will also emit an change event.

Arguments

1. newValue (Any)

on(event, handler)

Listen for a custom event on the current instance.

Arguments

1. event (String): Event type.
2. handler (Function): Event handler.

Return

(Function): off.

once(event, handler)

Listen for a custom event, but only once.

Arguments

1. event (String): Event type.
2. handler (Function): Event handler.

Return

(Function): off.

off([event, handler])

Remove event listener(s).

Arguments

1. event (String): Event type.
2. handler (Function): Event handler.

hoc(propName)

Create React HOC.

Arguments

1. propName (String): Inject this value as prop.

Return

(Function): A HOC creator function.

Example

Basic usage:

import React, { Component, PropTypes } from 'react';
import Wormhole from 'react-wormhole-hoc';

const myWormhole = new Wormhole('awesome!!1');

class App extends Component {
	static propTypes = {
		myValue: PropTypes.string,
	};

	render() {
		return (
			<h1>{this.props.myValue}</h1>
		);
	}
}

const hoc = myWormhole.hoc('myValue');
export default hoc(App);

With transform-decorators-legacy babel plugin:

@myWormhole.hoc('myValue')
export default class App extends Component {
	// the same with above...
}

static connect(mapProps[, options])

Connect some wormholes to a HOC.

Arguments

1. mapProps (Object|Function): Define a key-value object to props. A value should be a wormhole instance or a function. If a value is a type of String, Number, Boolean, Array or a plain Object, it would be converted to wormhole instance.
2. options (Object): See below for detail.

Available options:

• isPure (Boolean): Use pureComponent or not. Default value: true.
• withRef (Boolean): If true, stores a ref to the wrapped component instance and makes it available via getWrappedInstance() method. Default value: false.
• hoistMethods ([String]): Copies wrapped component instance methods to HOC instance. Make sure set withRef: true first. Default value: [].

Example

Basic usage:

@Wormhole.connect({
	hello: 'hello',

	/* or: */
	// hello: new Wormhole('hello'),

	world: 'world',
})
class App extends Component {
	static propTypes = {
		hello: PropTypes.string,
		world: PropTypes.string,
	};

	render() {
		const { hello, world } = this.props;
		return (
			<h1>{hello} {world}</h1>
		);
	}
}

With methods:

@Wormhole.connect({
	counter: 1,
	increase(ev) {
		ev.preventDefault();
		this.counter.set(this.counter.get() + 1);
	},
})
class App extends Component {
	static propTypes = {
		counter: PropTypes.number,
		increase: PropTypes.func,
	};

	render() {
		const { counter, increase } = this.props;
		return (
			<div>
				<p>{counter}</p>
				<button onClick={increase} />
			</div>
		);
	}
}

static <Provider wormholes />

Makes the wormholes available to the connect() calls in the component hierarchy below. It's useful when using server-side rendering. See below example for detail.

Props

• wormholes (Object): A key/value object of wormholes.
• children (ReactElement): The root of your component hierarchy.

Example

import React from 'react';
import ReactDOM from 'react-dom';
import Wormhole, { Provider } from 'react-wormhole-hoc';
import MyRootComponent from './MyRootComponent';

@Wormhole.connect((wormholes) => ({ // `wormholes` is provided by `<Provider>`.
	page: wormholes.page
}))
class App extends Component {
	static propTypes = {
		page: PropTypes.object,
	};

	render() {
		const { page } = this.props;
		return (
			<div>{page}</div>
		);
	}
}

const MyRootComponent = () => (<App />);

const wormholes = {
	page: {},
	isFetching: false,
	errorMessage: '',
};

ReactDOM.render(
	<Provider wormholes={wormholes}>
		<MyRootComponent />
	</Provider>,
	rootEl,
);

Return

(Function): A HOC creator function.

Installing

Using npm:

npm install --save react-wormhole-hoc

Using yarn:

yarn add react-wormhole-hoc

Dependencies

react-wormhole-hoc has very few dependencies and most are managed by NPM automatically. However the following peer dependencies must be specified by your project in order to avoid version conflicts: react, react-addons-shallow-compare, and NPM will not automatically install these for you but it will show you a warning message with instructions on how to install them.

Related Projects

• https://github.com/ReactTraining/react-broadcast
• https://github.com/gnoff/react-tunnel

License

MIT © Cap32