redux-paginator-immutable/src/createItemReducer.js

// @flow

import type { PaginatorSettings } from "./types";

import { createSelector } from "reselect";

/*
  Use to create a simple list where you do not need more information about
  the item. For instance, if you do NOT need to fetch more data or
  manipulate it
*/
const createReducer = ({ key } : PaginatorSettings) => {
  const
    getItems = (state : any) => state.getIn([
      "entities",
      key,
    ]),
    getItem = createSelector(
      getItems,
      (state, id) => id,
      (data, id) => data.get(id)
    ),
    getItemsList = createSelector(
      getItems,
      (data) => data.toList()
    );

  return {
    getItems,
    getItem,
    getItemsList,
  };
};

export default createReducer;