1.
How should you
React to Redux

2.
What's redux?

3.
Redux
State container
Implements Flux

4.
Unidirectional

5.
Actions
actions don't do anything
only contain information
have no idea how to update a store

6.
Actions
function addTodo(task) {
return {
type: 'ADD_TODO',
payload: task,
};
}

7.
Actions - test
describe('TodoAction creator', () => {
it('should create ADD_TODO action', () => {
const expectedAction = {
type: 'ADD_TODO',
payload: 'test',
};
expect(todoAction('test')).to.be.deep.equal(expectedAction);
});
});

8.
Dispatcher
can register stores (listeners)
sends actions to all stores (listeners)
have no idea how to update a store

9.
Store
listens for actions
creates new state from old state and action
knows how to update a store

10.
Store - reducer
function todoReducer(state = initialState, action) {
switch (action.type) {
case 'ADD_TODO':
return {
...state,
list: [
...state.list,
action.payload,
],
};
default:
return state;
}
}

11.
Reducer - test
describe('todoReducer', () => {
it('should return initial state', () => {
expect(todoReducer(undefined, {})).to.be.deep.equal(initialState);
});
it('should add element to list', () => {
const name = 'testName';
const action = {
type: 'ADD_TODO',
payload: name,
};
const expectedState = {
list: [
name,
],
};
expect(todoReducer(initialState, action)).to.be.deep.equal(expectedState);
});
});

12.
View
represents current state
can should listen for store updates
have no idea how to update a store

13.
class TodoList extends Component {
static propTypes = {
list: PropTypes.array,
};
render() {
const { list } = this.props;
return (<div>
<ul>
{list.map(element => <li key={key}>{element}</li>)}
</ul>
</div>
);
}
}
export default connect(
state => ({
list: state.todo.list,
})
)(TodoList);

14.
How to update the state?
view can send action to dispatcher
have no idea how to update a store
does not have to know what happens next
only what it wants to achieve

15.
class TodoList extends Component {
static propTypes = {
list: PropTypes.array,
addItem: PropTypes.func,
};
render() {
const { list } = this.props;
return (<div>
<button onClick={() => this.props.addItem('New item')}/>
<ul>
{list.map(element => <li key="{key}">{element}</li>)}
</ul>
</div>
);
}
}
export default connect(
state => ({
list: state.todo.list,
}),
{
addItem,
}
)(TodoList);

16.
Let's code!

17.
Thank you!