Beginner question.
I want to pass a user object to a component from store as a prop, but the component doesn't get it (undefined). I get the user object from a third party service authentication service (google firebase)
The middleware actually logs out in the console that the action of type SET_CURRENT_USER takes place, and next state indeed will have a user.currentUser set to the object returned from the login service (NOT UNDEFINED).
However, the component doesn't re-render and doesn't seem to receive the object as prop
The component, in which the prop is undefined
import React from 'react';
import { connect } from 'react-redux';
import { auth } from "../../firebase/firebase.utils";
export const Navbar = ({ currentUser }) => {
return (
/* A LOT OF JSX CODE. currentUser IS UNDEFINED */
);
};
const mapStateToProps = state => ({
currentUser: state.user.currentUser
});
export default connect(mapStateToProps)(Navbar);
The App component, which has the above component as a child. Also, I'm trying to set the store to contain the user object in the componentDidMount()
import React from 'react';
import Homepage from "./pages/homepage";
import { Route, Switch } from 'react-router-dom';
import { connect } from 'react-redux';
import Login from "./pages/login";
import Register from "./pages/register";
import { Navbar } from "./components/navbar/navbar";
import { auth } from "./firebase/firebase.utils";
import { setCurrentUser } from "./redux/user/user.actions";
class App extends React.Component {
unsubscribeFromAuth = null;
componentDidMount() {
this.unsubscribeFromAuth = auth.onAuthStateChanged(async userAuth => {
if(userAuth) {
(async () => {
const rawResponse = await fetch(/* JUST AN ASYNC FUNCTION TO POST TO BACKEND*/);
})();
}
this.props.setCurrentUser(userAuth); /*HERE IM TRYING TO SET THE STORE*/
})
}
componentWillUnmount() {
this.unsubscribeFromAuth();
}
render() {
return (
<div>
<Navbar /> /* THE COMPONENT WHICH SHOULD GET THE USER OBJECT AS PROP */
<Switch>
<Route exact={true} path={'/register'} component={Register} />
<Route exact={true} path={'/login'} component={Login} />
<Route path={'/'} component={Homepage} />
</Switch>
</div>
);
}
}
const mapDispatchToProps = (dispatch) => ({
setCurrentUser: user => dispatch(setCurrentUser(user))
});
export default connect(null, mapDispatchToProps)(App);
The index component
import React from 'react';
import ReactDOM from 'react-dom';
import App from "./App";
import { BrowserRouter } from "react-router-dom";
import { Provider } from 'react-redux';
import store from "./redux/store";
ReactDOM.render(
<Provider store={store} > /* HERE IS STORE PROVIDED FROM IMPORT*/
<BrowserRouter>
<App/>
</BrowserRouter>
</Provider>,
document.getElementById('root')
);
Root reducer
import { combineReducers } from "redux";
export default combineReducers({
user: userReducer
});
User reducer
const INITIAL_STATE = {
currentUser: null
};
const userReducer = (state = INITIAL_STATE, action) => {
switch (action.type) {
case 'SET_CURRENT_USER':
return {
...state,
currentUser: action.payload
};
default:
return state;
}
};
export default userReducer;
User action
export const setCurrentUser = user => ({
type: 'SET_CURRENT_USER',
payload: user
});
The store
import { createStore, applyMiddleware } from "redux";
import logger from 'redux-logger';
import rootReducer from './root-reducer';
const middlewares = [logger];
const store = createStore(rootReducer, applyMiddleware(...middlewares));
export default store;
You're doing both a named and default export for Navbar. The default export gets wrapped by the connect HOC that adds currentUser to its props. The named export does not.
You import it named like this: import { Navbar } from. Instead use the default export: import Navbar from.
Then I would suggest removing the named export to avoid future confusion.
Related
I am building an app prototype that essentially simulates ecommerce. I have components that each have different items that can be added to a cart(below I just show an example of how one would basically work). These components are accessed via different routes using the react-router. There is a header component that displays the number of items currently in the cart. The header gets the number of items in the cart from the state in the redux store. However, if I navigate to a new route, the store goes back to the default state. I need the the store to keep its state when a new route is navigated to. For example, if I go to the ShoppingPage, add an item to the cart, and then go back to the Home page, I need the cart to still have an item in it.
actions.js
export const actionTypes = Object.freeze({
UPDATE_CART: Symbol('UPDATE_CART'),
});
export const updateCart = (payload) => {
return {
type: actionTypes.UPDATE_CART,
payload,
};
};
export default actionTypes;
reducer.js
import actions from './actions';
export const INITIAL_STATE = {
cart: [],
};
export default (state = INITIAL_STATE, action) => {
switch (action.type) {
case actions.UPDATE_CART: {
return {
...state,
cart: action.payload,
};
}
default: {
return state;
}
};
};
index.js
import React from 'react';
import ReactDOM from 'react-dom';
import App from './App';
import * as serviceWorker from './serviceWorker';
import { BrowserRouter } from 'react-router-dom';
import { Provider } from 'react-redux';
import { createStore } from 'redux';
import reducer, { INITIAL_STATE } from './reducer';
const store = createStore(reducer, INITIAL_STATE);
console.log(store.getState());
ReactDOM.render(
<Provider store ={store}>
<BrowserRouter>
<App />
</BrowserRouter>
</Provider>
, document.getElementById('root'));
serviceWorker.unregister();
ShoppingPage.js
import React, { Component } from 'react';
import { connect } from 'react-redux';
import { updateCart } from './actions';
class ShoppingPage extends Component {
addToCart = () => {
const cart = [...this.props.cart];
cart.push('new item');
this.props.modifyCart(cart);
render() {
return(
<div>
<button onClick={addToCart}>
Add To Cart
</button>
</div>
)
}
}
const mapDispatchToProps = dispatch => ({
modifyCart: payload => dispatch(updateCart(payload)),
});
const mapStateToProps = state => ({
cart: state.cart,
});
export default connect(
mapStateToProps,
mapDispatchToProps,
)(ShoppingPage);
Home.js
import React, { Component } from 'react';
import { ListGroup, ListGroupItem } from 'reactstrap';
class Home extends Component {
render() {
return(
<div>
<ListGroup>
<ListGroupItem><a href='/ShoppingPage'>ShoppingPage</a></ListGroupItem>
</div>
)
}
}
export default Home;
Header.js
import React, { Component } from 'react';
import { Navbar, NavbarBrand } from 'reactstrap';
import { connect } from 'react-redux';
class Header extends Component {
render() {
return(
<Navbar sticky='top' className='nav'>
<NavbarBrand href='/'>Online Shopping</NavbarBrand>
<span>{'Items in Cart: '}{this.props.cart.length}</span>
</Navbar>
)
}
}
const mapStateToProps = state => ({
cart: state.cart,
});
export default connect(
mapStateToProps
)(Header);
Routes.js
import React from 'react';
import { Switch, Route } from 'react-router-dom';
import Home from './Home';
import ShoppingPage from './ShoppingPage';
const Routes = () => (
<Switch>
<Route exact path='/' component={Home} />
<Route exact path='/ShoppingPage' component={ShoppingPage} />
</Switch>
);
export default Routes;
App.js
import React from 'react';
import Routes from './Routes';
import Header from './Header';
function App() {
return (
<div>
<Header />
<Routes />
</div>
);
}
export default App;
What's likely happening is that during navigation the web app "reloads" again (which is wiping the redux state). In order to navigate with react router you want to look at <Link>.
For example,
Home.js
<a href='/ShoppingPage'>ShoppingPage</a>
should be changed to:
<Link to="/ShoppingPage">ShoppingPage</Link>
I've just started out with Redux and trying to implement a simple MERN App (for practice).
Everything in my code is working fine, but my reducer function is showing unexpected behaviour. When an action (which gets fetches data from express api) is called my reducer correctly goes to the particular switch case data logs successfully but then three times the default case is passed and data on my component which I log is showing null. Please Help.
Here's my code:-
index.js
import React from 'react';
import ReactDOM from 'react-dom';
import './index.css';
import App from './App';
import { BrowserRouter as Router } from 'react-router-dom';
import { Provider } from 'react-redux';
import thunk from 'redux-thunk';
import { createStore, applyMiddleware, combineReducers } from 'redux';
import articlesReducer from './store/reducers/articlesReducer';
import registerServiceWorker from './registerServiceWorker';
const rootReducer = combineReducers({
articles: articlesReducer
});
const store = createStore(rootReducer, applyMiddleware(thunk));
const app = (
<Provider store={store}>
<Router>
<App />
</Router>
</Provider>
);
ReactDOM.render(app, document.getElementById('root'));
registerServiceWorker();
App.js
import React, {Component} from 'react';
import {Switch, Route} from 'react-router-dom';
import './App.css';
import Home from './components/Home/Home';
class App extends Component {
render() {
return (
<div>
<Switch>
<Route exact path="/" component={Home} />
</Switch>
</div>
);
}
}
export default App;
articles.js
export const getAllArticles = () => {
return dispatch => {
return (
fetch('http://localhost:5000/api/articles')
.then(res => res.json())
.then(data => {
dispatch({type: 'GET_ALL_ARTICLES', articles: data})
})
);
};
};
articlesReducer.js
const initialState = {
articles:null
};
const reducer = (state = initialState, action) => {
switch (action.type) {
case 'GET_ALL_ARTICLES':
console.log('in reducer', action.type, action.articles[0]);
return {
...state,
articles: action.articles
};
default:
console.log('In default');
return state;
}
};
export default reducer;
myComponent
import React, { Component } from 'react';
import { connect } from 'react-redux';
import { getAllArticles } from '../../store/actions/articles.js';
class MainPage extends Component {
componentWillMount() {
this.props.initArticles();
console.log(this.props.articles);
}
render() {
return (
<div className="container">
<br />
<h1>Here comes the articles!!</h1>
</div>
);
}
}
const mapStateToProps = state => {
return {
articles: state.articles
};
};
const mapDispatchToProps = dispatch => {
return {
initArticles: () => dispatch(getAllArticles())
};
};
export default connect(mapStateToProps, mapDispatchToProps)(MainPage);
The output in my console is somewhat like this:-
In default
In default
In default
{articles: null}
in reducer GET_ALL_ARTICLES {articles[0] Object}
I don't know what is the mistake. Thanks for help in advance.
I'm not sure whether this is actually the problem but you incorrectly access the articles. You have a root reducer with articles reducer:
const rootReducer = combineReducers({
articles: articlesReducer
});
which initial state is:
const initialState = {
articles:null
};
And in your mapDispatchToProps you "import" whole reducer state:
const mapStateToProps = state => {
return {
articles: state.articles
};
};
I think you wanted to access articles property
const mapStateToProps = state => {
return {
articles: state.articles.articles
};
};
Other than that everything seems to be fine. I would however as pointed in comment initialize articles as empty array [].
const initialState = {
articles: []
};
My connected component doesn't re-render after the redux store is changed.
The store structure:
{
user: {
profile: {
email: null
}
}
}
I am dispatching an UPDATE action creator:
dispatch(profile.actions.update({email: 'blah#blah.com'}));
which updates the store state, but does not re-render the connected ProfilePage component!
-
/ ProfilePage.js (the connected component)
//component omitted
function mapStateToProps(state) {
return {
initialFormValues: state.user.profile
}
}
export default connect(mapStateToProps)(ProfilePage)
/ profileReducer.js (where the update action is intercepted)
export default function(state = { email: null }, action) {
switch (action.type) {
case t.UPDATE:
return { ...state, ...action.values }; //this is a new object (not mutated)
default:
return state;
};
};
/ userReducer.js
import { combineReducers } from 'redux';
import session from './session';
import profile from './profile';
export default combineReducers({
profile: profile.reducer
});
/ rootReducer.js
import {combineReducers} from 'redux';
import {routerReducer as router} from 'react-router-redux';
import { reducer as form } from 'redux-form';
import user from './modules/user';
const rootReducer = combineReducers({
form,
user: user.reducer,
router
})
export default rootReducer;
/ store.js
import reducer from './rootReducer';
import thunk from 'redux-thunk'
import logger from 'redux-logger'
import { createStore, compose, applyMiddleware } from 'redux';
import { routerMiddleware as router } from 'react-router-redux';
export default function(history) {
return createStore(
reducer,
compose(
applyMiddleware(
router(history),
thunk,
logger
)
)
)
}
My guess is that the user object is the same object as it was before the update - thus redux assumes nothing changed. The profile reducer and using combineReducers in user seems unnesscary and is probably having unintended consequences. You should add a profile field in the user reducer directly and return a new user object. Better yet just put the email field in the user object and ditch profile all together.
I seem to have accidentally initialized two separate store instances. The dispatch (called when the App component mounts) was using a different store. That is why it was not rerendering
class App extends Component {
componentDidMount(props) {
const jwt = localStorage.getItem('jwt');
if(!!jwt) {
** store(history).dispatch(user.actions.fetchUserData(jwt)) // the offending code
}
}
render() {
return (
<Provider store={ store(history) }> // And here a different store instance
<ConnectedRouter history={ history }>
<AppWrapper>
<MainNav />
<Main>
<Switch>
<Route path="/login"
component={ LoginPage } />
<Route path="/register"
component={ RegisterPage } />
</Switch>
</Main>
</AppWrapper>
</ConnectedRouter>
</Provider>
);
}
}
export default App;
Not sure why I'm getting this error, it happened when I added connect from redux to my Login component, so I could connect my store.
FAIL src/components/auth/Login.test.js
● Test suite failed to run
Invariant Violation: Could not find "store" in either the context or props of "Connect(LoginContainer)". Either wrap the root component in a <Provider>, or explicitly pass "store" as a prop to "Connect(LoginContainer)".
Index.js
import React from 'react'
import ReactDOM from 'react-dom'
import { Provider } from "react-redux"
import { createCommonStore } from "./store";
import App from './App'
import css from './manage2.scss'
const store = createCommonStore();
const element = document.getElementById('manage2');
console.log("Index.js Default store", store.getState());
ReactDOM.render(
<Provider store={store}> // <-- store added here
<App />
</Provider>, element);
store.js
import React from "react"
import { applyMiddleware, combineReducers, compose, createStore} from "redux"
import thunk from "redux-thunk"
import { userReducer } from "./reducers/UserReducer"
import { authReducer } from "./reducers/AuthReducer"
export const createCommonStore = (trackStore=false) => {
const reducers = combineReducers({
user: userReducer,
user: authReducer
});
//noinspection JSUnresolvedVariable
const store = createStore(reducers,
compose(
applyMiddleware(thunk),
window.__REDUX_DEVTOOLS_EXTENSION__ && window.__REDUX_DEVTOOLS_EXTENSION__()
)
);
if (trackStore) {
store.subscribe((() => {
console.log(" store changed", store.getState());
}));
}
return store;
};
App.js
import React from 'react'
import { BrowserRouter as Router } from 'react-router-dom'
import Routes from './components/Routes'
const supportsHistory = "pushState" in window.history
export default class App extends React.Component {
render() {
return (
<Router forceRefresh={!supportsHistory}>
<Routes />
</Router>
);
}
}
Routes.js
import React from 'react'
import { Route, Switch } from 'react-router-dom'
import LoginContainer from './auth/Login'
import Dashboard from './Dashboard'
import NoMatch from './NoMatch'
const Routes = () => {
return (
<Switch>
<Route exact={ true } path="/" component={ LoginContainer }/>
<Route path="/dashboard" component={ Dashboard }/>
<Route component={ NoMatch } />
</Switch>
);
}
export default Routes
Finally Login.js (code removed for brevity
import React from 'react'
import { connect } from "react-redux"
import { bindActionCreators } from 'redux';
import { setCurrentUser } from '../../actions/authActions'
import * as api from '../../services/api'
const mapDispatchToProps = (dispatch) => {
console.log('mapDispatchToProps', dispatch);
return {
setUser: (user) => {
bindActionCreators(setCurrentUser(user), dispatch)
}
}
}
class LoginContainer extends React.Component {
constructor(props) {
super(props)
this.state = {};
this.handleChange = this.handleChange.bind(this);
this.handleSubmit = this.handleSubmit.bind(this);
}
handleChange(e) {
}
handleSubmit(e) {
}
render() {
return (
<div className="app-bg">
...
</div>
)
}
}
export default connect(null, mapDispatchToProps)(LoginContainer);
Login.test
import React from 'react'
import ReactTestUtils from 'react-dom/test-utils'
import { mount, shallow } from 'enzyme'
import toJson from 'enzyme-to-json'
import { missingLogin } from '../../consts/errors'
import Login from './Login'
import Notification from '../common/Notification'
const loginComponent = shallow(<Login />);
const fakeEvent = { preventDefault: () => '' };
describe('<Login /> component', () => {
it('should render', () => {
const tree = toJson(loginComponent);
expect(tree).toMatchSnapshot();
});
it('should render the Notification component if state.error is true', () => {
loginComponent.setState({ error: true });
expect(loginComponent.find(Notification).length).toBe(1);
});
});
describe('User Login', () => {
it('should fail if no credentials are provided', () => {
expect(loginComponent.find('.form-login').length).toBe(1);
loginComponent.find('.form-login').simulate('submit', fakeEvent);
expect(loginComponent.find(Notification).length).toBe(1);
const notificationComponent = shallow(<Notification message={ missingLogin }/>);
expect(notificationComponent.text()).toEqual('Please fill out both username and password.');
});
it('input fields should be filled correctly', () => {
const credentials = { username: 'leongaban', password: 'testpass' };
expect(loginComponent.find('#input-auth-username').length).toBe(1);
const usernameInput = loginComponent.find('#input-auth-username');
usernameInput.value = credentials.username;
expect(usernameInput.value).toBe('leongaban');
const passwordInput = loginComponent.find('#input-auth-password');
passwordInput.value = credentials.password;
expect(passwordInput.value).toBe('testpass');
});
});
What do you see wrong here?
Redux recommends exporting the unconnected component for unit tests. See their docs.
In login.js:
// Named export for tests
export class LoginContainer extends React.Component {
}
// Default export
export default connect(null, mapDispatchToProps)(LoginContainer);
And in your test:
// Import the named export, which has not gone through the connect function
import { LoginContainer as Login } from './Login';
You can then specify any props that would have come from the store directly on the component.
You need to pass store as either a prop or context in your test. mount method accepts context as another parameter.
and how do you get store here? You create store the same way you created in app.js
You could use React's contextType or pass propType. You would need to declare it either as a prop or contextType.
Provider.contextTypes = {
Store: React.PropTypes.object.isRequired
};
Provider.propTypes= {
Store: React.PropTypes.object.isRequired
};
I'm having problems with misconfigured Redux after merging contents of multiple files into one to serve as config for Redux.
How to resolve store, while keeping this in one file?
Unhandled JS Exception: Could not find "store" in either the context
or props of "Connect(App)". Either wrap the root component in a
, or explicitly pass "store" as a prop to "Connect(App)".
'use strict';
import React, { Component } from 'react';
import { createStore, applyMiddleware, combineReducers, bindActionCreators } from 'redux';
import { Provider, connect } from 'react-redux';
import thunk from 'redux-thunk';
import * as screenActions from './redux/actions/screenActions';
import * as reducers from './redux/stores/reducers';
const createStoreWithMiddleware = applyMiddleware(thunk)(createStore);
const reducer = combineReducers(reducers);
const store = createStoreWithMiddleware(reducer);
import RootContainer from './redux/views/containers/rootContainer';
class App extends Component {
render() {
const { state, actions } = this.props;
return (
<Provider store={store}>
<RootContainer />
</Provider>
);
}
}
export default connect(
(state) => ({
state: state.reducer
}),
(dispatch) => ({
actions: bindActionCreators(screenActions, dispatch)
})
)(App);
Provider, passes the store to the component nested within it and generally only needed to be applied to the root component (in your case <RootContainer>
connect connect with the component providing store and not the component that has store provided to it.
SUGGESTED SOLUTION:
MOVE the connect to the <RootContainer> component file instead, and pass connect the RootContainer and not the App component:
export default connect(
(state) => ({
state: state.reducer
}),
(dispatch) => ({
actions: bindActionCreators(screenActions, dispatch)
})
)(RootContainer); // <<--- here :)
UPDATE:
Given the OP wants to achieve all of this in the same file, you'll have to create a React element that represents your Redux container created from connect, so:
'use strict';
import React, { Component } from 'react';
import { createStore, applyMiddleware, combineReducers, bindActionCreators } from 'redux';
import { Provider, connect } from 'react-redux';
import thunk from 'redux-thunk';
import * as screenActions from './redux/actions/screenActions';
import * as reducers from './redux/stores/reducers';
const createStoreWithMiddleware = applyMiddleware(thunk)(createStore);
const reducer = combineReducers(reducers);
const store = createStoreWithMiddleware(reducer);
import RootContainer from './redux/views/containers/rootContainer';
// name has to be capitalised for React to recognise it as an element in JSX
const ConnectedRoot = connect(
(state) => ({
state: state.reducer
}),
(dispatch) => ({
actions: bindActionCreators(screenActions, dispatch)
})
)(RootContainer);
class App extends Component {
render() {
const { state, actions } = this.props;
return (
<Provider store={store}>
<ConnectedRoot /> <------USE IT HERE
</Provider>
);
}
}
I had such a problem when I used:
import connect from "react-redux/lib/connect/connect";
instead of that, use:
import {connect} from "react-redux";
In your root index put the provider.
<Provider store={store}>
<App />
</Provider>,