Reux Data Dispatch

An enhancer to redux reducers that makes it easy to define dependent reducers to store data returned by a single action. This promotes a modular redux design where each reducer is responsible for storing one type of data.

This package works best when used in conjunction with Normalizr.

Install

Using npm

npm install redux-data-dispatch

Or yarn

yarn add redux-data-dispatch

Example

We're building an application that lets you search repositories on GitHub. The search endpoint returns a list of repositories, and each repository contains data relating to different entities. In this example, let's assume it returns data for:

• the repo (e.g. id, name, created_on, stargazers, ...)
• the owner (e.g. id, name, url, ...)

However, we want to keep repo specific data in the repo reducer and send owner data to the owner reducer. With redux data dispatch this is easy! 🤓

index.js

import React from 'react'
import ReactDOM from 'react-dom'
import { createStore, applyMiddleware } from 'redux'
import { Provider } from 'react-redux'
import dataDispatch from 'redux-data-dispatch'

import reducer from './reducer'
import App from './App'

// Setup the store with middleware
const store = (initialState) => createStore(
  reducer,
  initialState,
  applyMiddleware(dataDispatch)
)

// Render the app
ReactDOM.render(
  <Provider store={store()}>
    <App />
  </Provider>,
  document.getElementById('root')
)

repo/actions.js

import axios from 'axios'
import { repo } from './schema'

// action types
export const GET_REPOS_REQUEST = 'GET_REPOS_REQUEST'
export const GET_REPOS_SUCCESS = 'GET_REPOS_SUCCESS'
export const GET_REPOS_FAILURE = 'GET_REPOS_FAILURE'

// action to search github repos
export const getRepos = (repoName) => (dispatch) => {
  dispatch({ type: GET_REPOS_REQUEST })
  return axios.get('https://api.github.com/search/repositories', {
    params: { q: repoName }
  })
    .then(res => (
      // normalize the response to get response data in shape:
      // {
      //   entities: { repos: {...}, owners: {...} },
      //   result: [...]
      // }
      normalize(res.data, { item: [repo] }))
    )
    .then(normalised => dispatch({
      // dispatch the action as normal...
      type: GET_REPOS_SUCCESS,
      payload: normalised,
      // ...and to send to other reducers, just add a `deps` key
      // to the `action.meta` object
      meta: {
        // keys:   specify which reducer to send an action to
        // values: select which data in this action to send
        deps: { owner: 'payload.entities.owners' }
      }
    }))
    .catch(err => dispatch({
      type: GET_REPOS_FAILURE,
      payload: err,
      error: true
    }))
}

owner/reducer.js

import { listenFor } from 'redux-data-dispatch'

const initialState = {
  entities: {},
  order: [],
  error: null,
  loading: false
}

const reducer = (state = initialState, action) => {
  switch (action.type) {
    default:
      return state
  }
}

// Identify this reducer as `owner` in dataDispatch
export default listenFor('owner')(reducer)

API

dataDispatch <function>

import dataDispatch from 'redux-data-dispatch'

Supply to applyMiddleware to add data dispatch functionality to your app.

Example

store.js

import { applyMiddleware } from 'redux'
import dataDispatch from 'redux-data-dispatch'

applyMiddleware([dataDispatch])

actions.js

// If you want an action to dispatch to other reducers then just add pass an
// object specifying which reducers and payload to call as a second argument
// to dispatch
const doSomething = () => dispatch => {
  dispatch({
    type: 'FOO',
    payload: { a: 1, b: 2 },
    meta: {
      deps: { reducerKey: 'payload.b' }
      // ...or: deps: { reducerKey: action => action.payload.b }
    }
  })
}

listenFor <function>

import { listenFor } from 'redux-data-dispatch'

Arguments

• key <string>: a key that uniquely identifies this reducer.

Returns

Returns a function that accepts the reducer to identify with key.

Example

import { listenFor } from 'redux-data-dispatch'

const initialState = {
  entities: {}
}

const reducer = (state = initialState, action) => {
  switch (action.type) {
    default:
      return state
  }
}

export default listenFor('key-name')(reducer)