React状态管理器Rematch的使用详解

- 如何初始化`state`？ **state**
- 如何改变`state`？ **reducers**
- 如何处理异步`actions`？ **effect** with async/await

// ./models/countModel.js
export const count = {
  state: 0, // 初始化状态
  reducers: {
    // reducers中使用纯函数来处理状态的变化
    increment(state, payload) {
      return state = payload
    },
  },
  effects: dispatch => ({
    // effects中使用非纯函数处理状态变化
    // 使用async/await处理异步的actions
    async incrementAsync(payload, rootState) {
      await new Promise(resolve => setTimeout(resolve, 1000))
      dispatch.count.increment(payload)
    }
  })
}

// ./models/index.js
import { count } from './count'

export const models = {
  count
}

// store.js
import { init } from '@rematch/core'
import * as models from './models'
const store = init({models})
export default store

const { dispatch } = store
// state = { count: 0 }
// reducers
dispatch({ type: 'count/increment', payload: 1 }) // state = { count: 1 }
dispatch.count.increment(1) // state = { count: 2 }
// effects
dispatch({ type: 'count/incrementAsync', payload: 1 }) // 延时1秒后 state = { count: 3 }
dispatch.count.incrementAsync(1) // 延时1秒后 state = { count: 4 }

// App.js
import React from 'react'
import ReactDOM from 'react-dom'
import { Provider, connect } from 'react-redux'
import store from './store'

const Count = (props) => (
    <div>
        The count is {props.count}
        <button onClick={props.increment}>increment</button>
        <button onClick={props.incrementAsync}>incrementAsync</button>
    </div>
)
const mapState = (state) => ({
    count: state.count,
})

const mapDispatch = (dispatch) => ({
    increment: () => dispatch.count.increment(1),
    incrementAsync: () => dispatch.count.incrementAsync(1),
})

const CountContainer = connect(
    mapState,
    mapDispatch
)(Count)

ReactDOM.render(
    <Provider store={store}>
        <CountContainer />
    </Provider>,
    document.getElementById('root')
)