redux-store-emitter v1.0.0

Redux-store-emitter

Decoration for redux, that gives him the ability to distribute events.

Install

npm i redux-store-emitter -S

Usage

It used just like a redux.

import { createStore } from 'redux-store-emitter';
import rootReducer from './reducer';
const store = createStore(rootReducer);

Usage with Jest

Best way to use it with Jest is mock redux, by creating redux.js in __mocks__ directory.

// __mocks__/redux.js
export * from 'redux-store-emitter';

Then you can mock redux with jest:

jest.mock('redux');
import { createStore } from 'redux';

API

Decorator adds own methods to the function dispatch:

store.dispatch.on(actionName, callback):fn

Add a listener to the action. The callback function will be executed each time the target action will affect to the state.

Arguments:

• actionName {string} Action name
• callback {function} Event handler

Returns: {function} Listener destoyer

store.dispatch.on(
  ADD_TODO,
  action => console.log(action.todo)
);
store.dispatch(todo('Just do')); // <--
store.dispatch(todo('Just do it again')); // <--
// Console: Just do
// Console: Just do it again

An important fact is that the function will be called only when the action will trigger a subscription.

store.dispatch.after(actionName):promise

The promise will be resolved immediately if the action has already occurred or it will be resolved at the next action dispatch.

Arguments:

• actionName {string} Action name

Returns: {promise}

store.dispatch(todo('Just do')); // <--
store.dispatch.after(
  ADD_TODO
).then(action => console.log(action.todo));
// Console: Just do
store.dispatch(todo('Just do it again'));

Or:

store.dispatch.after(
  ADD_TODO
).then(action => console.log(action.todo));
store.dispatch(todo('Just do')); // <--
store.dispatch(todo('Just do it again'));
// Console: Just do

store.dispatch.record(actionName, callback):fn

The callback function will be called for each action that has already occurred and for each all next.

Arguments:

• actionName {string} Action name
• callback {function} Event handler

Returns: {function} Listener destoyer

store.dispatch(todo('Just do')); // <--
store.dispatch(todo('Just do it again')); // <--
store.dispatch(todo('Do it always')); // <--
store.dispatch.record(
  ADD_TODO,
  action => console.log(action.todo)
);
store.dispatch(todo('Forever')); // <--
// Console: Just do
// Console: Just do it again
// Console: Do it always
// Console: Forever

store.dispatch.before(actionName, callback):fn

The callback function will be called once before the action will be passed to the reducer. Thus, you get a state without the effect of the action.

Arguments:

• actionName {string} Action name
• callback {function} Event handler

Returns: {function} Listener destroyer

const INCREASE = 'INCREASE';
const INIT = { count: 1 };
function rootReducer(state = INIT, action) {
  switch (action.type) {
    case INCREASE:
      return {
        count: state.count + 1
      };
    default:
      return state;
  }
}

const store = createStore(rootReducer);
store.dispatch.before(
  INCREASE,
  () => console.log('before', store.getState().count)
);
store.dispatch.after(INCREASE)
.then(() => console.log('after', store.getState().count));
store.dispatch({ type: INCREASE }); // <~~
// Console: before 1
// Console: after 2

store.dispatch.beforeEach(actionName, callback):fn

The callback function will be called for each time, before the action will be passed to the reducer.

Arguments:

• actionName {string} Action name
• callback {function} Event handler

Returns: {function} Listener destroyer

Works same as method before, but countless times.

store.dispatch.waitFor(actionName):promise

The callback function will be executed once when the action will affect the state.

Arguments:

• actionName {string} Action name

Returns: {promise}

store.dispatch(todo('Do it'));
store.dispatch.waitFor(ADD_TODO)
.then(action => console.log);
store.dispatch(todo('Do it again')); // <--
// Console: Do it again

store.dispatch.clear()

Erases all actions history.

Author

Vladimir Kalmykov vladimirmorulus@gmail.com

License

MIT