redux-immutable

redux-immutable is used to create an equivalent function of Redux combineReducers that works with Immutable.js state.

When Redux createStore reducer is created using redux-immutable then initialState must be an instance of Immutable.Iterable.

Problem

When createStore is invoked with initialState that is an instance of Immutable.Iterable further invocation of reducer will produce an error:

The initialState argument passed to createStore has unexpected type of "Object". Expected argument to be an object with the following keys: "data"

This is because Redux combineReducers treats state object as a plain JavaScript object.

combineReducers created using redux-immutable uses Immutable.js API to iterate the state.

Usage

Create a store with initialState set to an instance of Immutable.Iterable:

import {
  combineReducers
} from 'redux-immutable';

import {
  createStore
} from 'redux';

const initialState = Immutable.Map();
const rootReducer = combineReducers({});
const store = createStore(rootReducer, initialState);

Using with react-router-redux

react-router-redux routeReducer does not work with Immutable.js. You need to use a custom reducer:

import Immutable from 'immutable';
import {
  LOCATION_CHANGE
} from 'react-router-redux';

const initialState = Immutable.fromJS({
  locationBeforeTransitions: null
});

export default (state = initialState, action) => {
  if (action.type === LOCATION_CHANGE) {
    return state.merge({
      locationBeforeTransitions: action.payload
    });
  }

  return state;
};

Pass a selector to access the payload state and convert it to a JavaScript object via the selectLocationState option on syncHistoryWithStore:

import {
  browserHistory
} from 'react-router';
import {
  syncHistoryWithStore
} from 'react-router-redux';

const history = syncHistoryWithStore(browserHistory, store, {
  selectLocationState (state) {
    return state.get('routing').toJS();
  }
});

The 'routing' path depends on the rootReducer definition. This example assumes that routeReducer is made available under routing property of the rootReducer.