@re-frame/standalone v0.20.0

re-frame

JavaScript port of the popular ClojureScript library for pragmatic, flux-like state management. I highly recommend checking out re-frame's original documentation to learn about its philosophy, terminology, and patterns. All design credit goes to the original authors — thank you for the inspiration.

Why re-frame?

Re-frame helps make state management predictable, testable, and pragmatic. From a high-level, re-frame is flux-like with events and event handlers, which are similar to redux's actions and reducers. Compared to redux, re-frame is more feature complete out of the box, with built-in interceptors, effects, and subscriptions. You'll find that you can be productive without needing to reach for third-party middleware.

Getting Started

The quickest way to get started is by installing @re-frame/standalone, which bundles everything you'll need to build a typical application: a store to manage state, subscriptions to query it, first-class developer tools, and effects such as http since the real world is more complicated than TodoMVC.

yarn add @re-frame/standalone

Usage

import {createStore} from "@re-frame/standalone"

// You can optionally provide an initial value when creating a store.
const store = createStore({count: 0})

// Register event handlers — these are how you'll change the store's state.
store.registerEventDB("increment", db => ({...db, count: db.count + 1}))

// Register subscriptions with the store. Whenver the store's state changes,
// these subscriptions will be automatically recomputed.
store.registerSubscription("count", db => db.count)

// Subscriptions are just values! You can work with them just like any other
// piece of data, and even compose them together.
const count = store.subscribe(["count"])
count.watch((prev, next) => {
  // do something here, maybe?
})

// Dispatch events to the store.
store.dispatch(["increment"])
store.dispatch(["increment"]) // count will be 2 after this event is processed

React Integration

1. Make your store available via React context by using Provider from @re-frame/react at the top of your application. This will allow you to access subscriptions and dispatch events within the React tree.

Using Preact? Just use @re-frame/preact instead.

import React from "react"
import ReactDOM from "react-dom"
import {createStore} from "@re-frame/standalone"
import {Provider} from "@re-frame/react"

const store = createStore()

const App = () => (
  <Provider store={store}>
    <YourAppGoesHere />
  </Provider>
)

ReactDOM.render(<App />, document.getElementById("root"))

2. Subscribe to your store from within the tree.

import React from "react"
import {useSubscription} from "@re-frame/react"

const ChatList = () => {
  const chats = useSubscription(["chats"])
  return (
    <ol>
      {chats.map(chat => (
        <li key={chat.id}>{chat.title}</li>
      )}
    </ol>
  )
}

3. Dispatch events to your store.

import {h} from "preact"
import {useDispatch} from "@re-frame/preact"

// Dispatch will only fire once in this example
const ChatList = () => {
  useDispatch(["load-chats"])
  // ... more logic here
}

// Dispatch will fire every time `filter` changes
const ChatList = ({filter}) => {
  useDispatch(["load-chats", filter])
  // ... more logic here
}

// useDispatch also returns a "dispatch" function
const ChatList = () => {
  const dispatch = useDispatch() // does not dispatch anything
  const onClick = () => {
    dispatch(["some-click-event"])
  }
  // ... more logic here
}

Supported Browsers

License

The MIT License (MIT)

Copyright (c) 2018 David Zukowski Copyright (c) 2015-2017 Michael Thompson

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.