entities-reducer

Entities Reducer

This package is a high-order reducer that updates state using entities from normalizr. By default, it expects the action to have a property of entities or to follow the flux-standard-action spec. However, it is possible to pass a data resolver (see Parameters) if your case doesn't match either of those.

Why

Why does this package exist?

One of the best things to store in redux is data from server requests. Additionally, working with items stored in redux is best done when the data is normalized. To simplify the storing of the data, this package will handle updating state with fresh normalized data.

Entities Reducer is a high-order reducer, which means it will accept more reducers for further customizations. The custom reducers are passed directly to combineRecuders from redux and should be passed into entities-reducers with the same format.

Installation

npm install --save entities-reducer
--- or ---
yarn add entities-reducer

Then add to your root reducer:

import { combineReducers } from 'redux';
import entitiesReducer from 'entities-reducer';

const rootReducer = combineReducers({
  entities: entitiesReducer({
    /* custom reducers here */
  }),
});

export default rootReducer;

Parameters

entitiesReducer(reducers, { dataResolver })

Reducers

Reducers are passed directly into combineReducers from redux, after the entities have been updated in state. It is called with the updated state and immediately returned.

dataResolver

The data resolver is a lookup function that is passed the action and returns the entities object to use while updating. If the data resolver returns a falsy value the entities-reducer will skip process and move directly to handling the custom reducers. Below is a customer dataResolver example, or you can checkout the default resolver. Example

const customDataResolver = (action) => {
  if (action.error) {
    return false;
  }
  return action.data.extra.normalized;
}