Redux doesn't work in React Native - class component - reactjs

this view doesn't work with redux, i need use redux dispatch inside react class component, but i get error
"Invalid hook call. Hooks can only be called inside of the body of a
function component. This could happen for one of the following
reasons:\n1. You might have mismatching versions of React and the
renderer (such as React DOM)\n2. You might be breaking the Rules of
Hooks\n3. You might have more than one copy of React in the same
app\nSee https://reactjs.org/link/invalid-hook-call for tips about how
to debug and fix this problem."
inspectionView.jsx
import React from "react";
import {
Text,
View,
} from "react-native";
import { useSelector, useDispatch } from 'react-redux';
import {
incrementByAmount,
selectCount
} from '../redux/slice.js';
export default class InspectionList extends React.Component {
constructor(props) {
super(props);
this.state = {
};
}
dispatch = useDispatch();
count = useSelector(selectCount);
render() {
return (
<View >
<Text>inspection view</Text>
<button
onClick={() => dispatch(incrementByAmount("hello world"))}
>
Add Amount
</button>
<Text>{{count}}</Text>
</View>
);
}
}
Slice.js
import { createSlice } from '#reduxjs/toolkit'
const initialState = {
value: 0,
}
export const counterSlice = createSlice({
name: 'counter',
initialState,
reducers: {
incrementByAmount: (state, action) => {
state.value = action.payload
},
},
})
// Action creators are generated for each case reducer function
export const {incrementByAmount } = counterSlice.actions
export const selectCount = (state) => state.counter.value;
export default counterSlice.reducer
store.js
import { configureStore } from '#reduxjs/toolkit'
import counterReducer from './slice'
export const store = configureStore({
reducer: {
counter: counterReducer,
},
})

The error is correct. You can never call any hook inside of a class component, regardless of whether it's a React-Redux hook, a React built-in hook, or any other hook. Only function components can call hooks.
My main advice here would be to write function components instead. There's no good reason to be writing class components today.
See the new React beta docs to learn how to use function components and hooks:
https://beta.reactjs.org
If for some reason you must use class components (and the odds are you don't need to), you can still use the older React-Redux connect API:
https://react-redux.js.org/tutorials/connect

Related

React Redux: state undefined

Playing around with react-redux and my state isCartVisible is showing undefined, I used simple functional components and I'm storing my stores in different files.
//main index.js file
import ReactDOM from 'react-dom/client';
import { Provider } from 'react-redux';
import './index.css';
import App from './App';
import store from './redux-store/store';
const root = ReactDOM.createRoot(document.getElementById('root'));
root.render(<Provider store={store}><App /></Provider>);
and
//App.js
import { useSelector } from "react-redux";
import Layout from "./components/Layout/Layout";
import Cart from "./components/Cart/Cart";
function App() {
const cartVisible = useSelector((state) => state.isCartVisible);
return (
<Layout>
{cartVisible && <Cart />}
</Layout>
);
}
and a component deep somewhere inside the app, by clicking the button I wanna toggle my <Cart> component
//CartButton.js
import { useDispatch } from "react-redux";
const CartButton = () => {
const dispatch = useDispatch();
const cartShowHandler = () => {
dispatch({ type: "cartToggle" });
};
return (
<button onClick={cartShowHandler}>
Click
</button>
);
};
and that's my store file, where I've created my store with reducer
import { createStore } from "redux";
const uiReducer = (state = { isCartVisible: true }, action) => {
if (action.type === "cartToggle") {
state.isCartVisible = !state.isCartVisible;
}
return state;
};
const uiStore = createStore(uiReducer);
export default uiStore;
You should never mutate the state. Your condition in reducer should look like this and it will work.
if (action.type === "cartToggle") {
return { ...state, isCartVisible: !state.isCartVisible};
}
As you have only one key in store in your example at the moment. You can do it this way also.
return { isCartVisible: !state.isCartVisible};
But it's always a good practice to return the whole state in your reducer's conditions.
Remember that redux do shallow comparison. Which means it checks if reference of an object is changed. In your case it wasnt changed.
Once, I wrote something about this topic in a blog post https://dev.to/machy44/shallow-comparison-in-redux-3a6
In Redux, you can only have one store. So it is very likely that your useSelector call actually tries to select data from another store than you are expecting it here.
You could validate that by using something like
const fullState = useSelector(state => state)
console.log(fullState)
That said, you are also writing a style of Redux here that is outdated by many years - in modern Redux you are not writing switch..case reducers or string action types. Also, createStore is deprecated at this point in favor of configureStore.
I would highly recommend you read about modern Redux and then follow the official Redux tutorial.
Whatever resources you have been following right now might have given you a very skewed view of how to use Redux.

How to access the Redux store outside of a component in React

I am beginning with Redux and I always used it in components with connect() and mapStateToProps(), but now I want to call my API with setInterval() every x time to check if the server has new data not stored in the Redux store, and substitute it.
My approach was to create a function that reads the store and update it like that:
import { store } from './dir/dir/store.js'
const refresher = async () => {
const state = store.getState();
// Call API, compare 'state.calendar' with calendar from server
// Call store.dispatch() if they are different, then update Redux store
}
export default refresher
My questions are:
Is this a good practise to use Redux?
Is there a better approach to this problem?
Thanks
It's perfectly fine to export the store and use within a vanilla js/ts file.
Example Redux Store
Make sure to export the store that you create
import { configureStore } from "#reduxjs/toolkit";
import { slice } from "../features/counterSlice";
export const store = configureStore({
reducer: {
counter: slice.reducer
}
});
Usage in Non-Component Code:
You can then import the created store in any other code
import { store } from "../App/store";
import { slice as counterSlice } from "../features/counterSlice";
export function getCount(): number {
const state = store.getState();
return state.counter.value;
}
export function incrementCount() {
store.dispatch(counterSlice.actions.increment());
}
Traditional Usage in Functional Component
import { useDispatch, useSelector } from "react-redux";
import { RootState } from "../App/store";
import { slice as counterSlice } from "../features/counterSlice";
export function Clicker() {
const dispatch = useDispatch();
const count = useSelector((state: RootState) => state.counter.value);
const dispatchIncrement = () => dispatch(counterSlice.actions.increment())
// ...
Example Slice
import { createSlice } from "#reduxjs/toolkit";
export const slice = createSlice({
name: "counter",
initialState: { value: 0 },
reducers: {
increment: (state) => {
state.value += 1;
}
}
});
Demo in Codesandbox
Note: You cannot use this option with Server Side Rendering. If you need to support SSR, you can use middleware to listen to dispatched actions and handle elsewhere.
Further Reading
What is the best way to access redux store outside a react component? | Stack Overflow
Access the Redux Store Outside a React Component | Blog
How can I access the store in non react components? | Github Issues
Here you can access the store and action out side any component like index.js file in react-native.
import {updateLocationAlertItem} from './src/store/actions/locationAlertAction';
import {store} from './src/store/index';
store.subscribe(listener);
function listener() {
state = store.getState().locationAlertReducer;
}
store.dispatch(
updateLocationAlertItem({
index: index,
is_in_radius: true,
is_notification: true,
arrival_time: moment().format('DD/MM/YYYY hh:mm'),
exit_time: item.exit_time,
}),
);

React Redux fetching data from backend approach

I'm a bit confused and would love an answer that will help me to clear my thoughts.
Let's say I have a backend (nodejs, express etc..) where I store my users and their data, and sometimes I wanna fetch data from the backend, such as the user info after he logs in, or a list of products and save them in the state.
My approach so far and what I've seen, I fetch the data before the component loads and dispatch an action with the data from the response.
But I recently started digging a bit about this and I saw react-thunk library which I knew earlier and started to wonder if what is the best practice of fetching from backend/API?
Has React Hooks change anything about this topic? Is it important to know this?
I feel a bit dumb but couldn't find an article or video that talks exactly about this topic :)
To do this best practice, use the following method:
I used some packages and patterns for best practice:
redux-logger for log actions and states in console of browser.
reselect Selectors can compute derived data, allowing Redux to
store the minimal possible state and etc.
redux-thunk Thunks are the recommended middleware for basic
Redux side effects logic, including complex synchronous logic that
needs access to the store, and simple async logic like AJAX requests
and etc.
axios for work with api (Promise based HTTP client for the
browser and node.js)
create a directory by name redux or any name of you like in src folder and
then create two files store.js and rootReducer.js in redux directory. We assume fetch products from API.
To do this:
Create a new directory by name product in redux directory and then
create four files by names product.types.js, product.actions.js,
product.reducer.js, product.selector.js in redux/product directory
The structure of the project should be as follows
...
src
App.js
redux
product
product.types.js
product.actions.js
product.reducer.js
rootReducer.js
store.js
Index.js
package.json
...
store.js
In this file we do the redux configuration
// redux/store.js:
import { createStore, applyMiddleware } from "redux";
import logger from "redux-logger";
import thunk from "redux-thunk";
import rootReducer from "./root-reducer";
const middlewares = [logger, thunk];
export const store = createStore(rootReducer, applyMiddleware(...middlewares));
rootReducer.js
The combineReducers helper function turns an object whose values are
different reducing functions into a single reducing function you can
pass to createStore.
// redux/rootReducer.js
import { combineReducers } from "redux";
import productReducer from "./product/product.reducer";
const rootReducer = combineReducers({
shop: productReducer,
});
export default rootReducer;
product.types.js
In this file we define constants for manage types of actions.
export const ShopActionTypes = {
FETCH_PRODUCTS_START: "FETCH_PRODUCTS_START",
FETCH_PRODUCTS_SUCCESS: "FETCH_PRODUCTS_SUCCESS",
FETCH_PRODUCTS_FAILURE: "FETCH_PRODUCTS_FAILURE"
};
product.actions.js
In this file we create action creators for handle actions.
// redux/product/product.actions.js
import { ShopActionTypes } from "./product.types";
import axios from "axios";
export const fetchProductsStart = () => ({
type: ShopActionTypes.FETCH_PRODUCTS_START
});
export const fetchProductsSuccess = products => ({
type: ShopActionTypes.FETCH_PRODUCTS_SUCCESS,
payload: products
});
export const fetchProductsFailure = error => ({
type: ShopActionTypes.FETCH_PRODUCTS_FAILURE,
payload: error
});
export const fetchProductsStartAsync = () => {
return dispatch => {
dispatch(fetchProductsStart());
axios
.get(url)
.then(response => dispatch(fetchProductsSuccess(response.data.data)))
.catch(error => dispatch(fetchProductsFailure(error)));
};
};
product.reducer.js
In this file we create productReducer function for handle actions.
import { ShopActionTypes } from "./product.types";
const INITIAL_STATE = {
products: [],
isFetching: false,
errorMessage: undefined,
};
const productReducer = (state = INITIAL_STATE, action) => {
switch (action.type) {
case ShopActionTypes.FETCH_PRODUCTS_START:
return {
...state,
isFetching: true
};
case ShopActionTypes.FETCH_PRODUCTS_SUCCESS:
return {
...state,
products: action.payload,
isFetching: false
};
case ShopActionTypes.FETCH_PRODUCTS_FAILURE:
return {
...state,
isFetching: false,
errorMessage: action.payload
};
default:
return state;
}
};
export default productReducer;
product.selector.js
In this file we select products and isFetching from shop state.
import { createSelector } from "reselect";
const selectShop = state => state.shop;
export const selectProducts = createSelector(
[selectShop],
shop => shop.products
);
export const selectIsProductsFetching = createSelector(
[selectShop],
shop => shop.isFetching
);
Index.js
In this file wrapped whole app and components with Provider for access child components to the store and states.
// src/Index.js
import React from "react";
import ReactDOM from "react-dom";
import App from "./App";
import { Provider } from "react-redux";
import { store } from "./redux/store";
ReactDOM.render(
<Provider store={store}>
<App />
</Provider>,
document.getElementById("root")
);
App.js class component
In this file we do connect to the store and states with class component
// src/App.js
import React, { Component } from "react";
import { connect } from "react-redux";
import { createStructuredSelector } from "reselect";
import {
selectIsProductsFetching,
selectProducts
} from "./redux/product/product.selectors";
import { fetchProductsStartAsync } from "./redux/product/product.actions";
class App extends Component {
componentDidMount() {
const { fetchProductsStartAsync } = this.props;
fetchProductsStartAsync();
}
render() {
const { products, isProductsFetching } = this.props;
console.log('products', products);
console.log('isProductsFetching', isProductsFetching);
return (
<div className="App">Please see console in browser</div>
);
}
}
const mapStateToProps = createStructuredSelector({
products: selectProducts,
isProductsFetching: selectIsProductsFetching,
});
const mapDispatchToProps = dispatch => ({
fetchProductsStartAsync: () => dispatch(fetchProductsStartAsync())
});
export default connect(
mapStateToProps,
mapDispatchToProps
)(App);
or App.js with functional component ( useEffect hook )
In this file we do connect to the store and states with functional component
// src/App.js
import React, { Component, useEffect } from "react";
import { connect } from "react-redux";
import { createStructuredSelector } from "reselect";
import {
selectIsProductsFetching,
selectProducts
} from "./redux/product/product.selectors";
import { fetchProductsStartAsync } from "./redux/product/product.actions";
const App = ({ fetchProductsStartAsync, products, isProductsFetching}) => {
useEffect(() => {
fetchProductsStartAsync();
},[]);
console.log('products', products);
console.log('isProductsFetching', isProductsFetching);
return (
<div className="App">Please see console in browser</div>
);
}
const mapStateToProps = createStructuredSelector({
products: selectProducts,
isProductsFetching: selectIsProductsFetching,
});
const mapDispatchToProps = dispatch => ({
fetchProductsStartAsync: () => dispatch(fetchProductsStartAsync())
});
export default connect(
mapStateToProps,
mapDispatchToProps
)(App);

Handling button state and actions in redux

I am new to react and redux.
Overview of app: I have a ToggleButtonGroup with two buttons. When a button is click I want to output a table for the respective button. The tables we filtered based on the button click.
Question: I am not sure how to setup an action, state and reducer in my project for the button functionality. My button is a component. Is it best practice to use actions and reducers for buttons? How would I pass these actions to other components? Any examples or resources is appreciated.
This is my Button.tsx file
import React, { Component, useState } from 'react'
import ToggleButtonGroup from 'react-bootstrap/ToggleButtonGroup';
import ToggleButton from 'react-bootstrap/ToggleButton';
function ToggleButtonGroupControlled() {
const [value, setValue] = useState([1, 2]);
return (
<ToggleButtonGroup type="checkbox" value={value} onChange={() => setValue(value)}>
<ToggleButton value={1}>PA Probes</ToggleButton>
<ToggleButton value={2}>Convential Probes</ToggleButton>
</ToggleButtonGroup>
);
}
export class Buttons extends Component {
render() {
return (
<div>
<ToggleButtonGroupControlled />
</div>
)
}
}
export default Buttons
This is my types.ts file
export const TOGGLE_PA_PROBES = 'TOGGLE_PA_PROBES';
export const TOGGLE_CONVENTIONAL_PROBES = 'TOGGLE_CONVENTIONAL_PROBES';
This is buttonAction.ts file
import{ TOGGLE_PA_PROBES, TOGGLE_CONVENTIONAL_PROBES } from './types';
export function togglePAProebs(){
}
export function toggleConventionalProbes(){
}
This is my buttonReducers.ts file
import{ TOGGLE_PA_PROBES, TOGGLE_CONVENTIONAL_PROBES } from '../Actions/types';
export function ButtonReducer(state, action){
switch(action.type){
default:
return state;
}
}
I will assume you know the basics of redux and react-redux. In short, you know that an action is dispatched to a store.
In a real world situation, it is as if you change a channel on your TV, (1) you dispatch a CHANGE_CHANNEL action to your remote control, (2) the remote control will receive the action dispatched and send that action with the channel information to your TV (reducer), then (3) your TV (reducer) will talk to your cable provider (store), and return the channel data back if it is available to you.
That flow is important because it can be used in your example as well. To begin with, imagine you have a store with some probes. On toggling your checkbox, you will dispatch an action FILTER, which will filter out the probes that need to be shown from a database list, for example, then call your reducer with the filtered probes to update your store and send that data back to your dispatcher.
When you first load your page, I also imagine you want to show the list of all your probes, so you would also need a FETCH action to be dispatched upon componentDidMount. Having that in mind, we can come up with a types file like this:
types.js
export const TOGGLE_PROBES = "TOGGLE_PROBES";
export const LOAD_PROBES = "LOAD_PROBES";
Now that the types are defined, we can create our actions,
import { TOGGLE_PROBES, LOAD_PROBES } from "./types";
const dbProbes = [
{ title: "pa probe 1", type: 1 },
{ title: "pa probe 2", type: 1 },
{ title: "conditional probe 1", type: 2 },
{ title: "conditional probe 1", type: 2 }
];
function toggleProbes(filtered) {
return {
type: TOGGLE_PROBES,
filtered: filtered
};
}
function loadProbes(probes) {
return {
type: LOAD_PROBES,
probes: probes
};
}
export function fetchProbes() {
return function(dispatch) {
dispatch(loadProbes(dbProbes));
};
}
export function filterProbes(filter) {
return function(dispatch) {
const filtered = dbProbes.filter(probe => filter.includes(probe.type));
dispatch(toggleProbes(filtered));
};
}
Notice that I created a fake list of probes called dbProbes. In a real world situation, you would probably be reaching out to a database to filter your probes.
After having all of the actions set up, you can finally work on the reducer and update your state accordingly,
import { TOGGLE_PROBES, LOAD_PROBES } from "./types";
const initialState = {
probes: []
};
function ButtonReducer(state = initialState, action) {
switch (action.type) {
case TOGGLE_PROBES:
return { ...state, probes: action.filtered };
case LOAD_PROBES:
return { ...state, probes: action.probes };
default:
return state;
}
}
export default ButtonReducer;
In order to be able to dispatch this in your components, you do need to set redux up. In your index.js, you could accomplish that by using both react, react-redux and react-thunk. React-thunk is a middleware which is often used with redux for async calls.
import React from "react";
import ReactDOM from "react-dom";
import { Provider } from "react-redux";
import { createStore, applyMiddleware } from "redux";
import thunk from "redux-thunk";
import "./styles.css";
import Buttons from "./Buttons";
import rootReducer from "./store/reducer";
const store = createStore(rootReducer, applyMiddleware(thunk));
const rootElement = document.getElementById("root");
ReactDOM.render(
<Provider store={store}>
<Buttons />
</Provider>,
rootElement
);
First, in your Button components, maybe you just want to show the initial list first, so to do that you need to use a react-redux high order component called connect, which will, as the name states, connect your store and map your store's state to dispatchers and props.
import React, { Component } from "react";
import ToggleButtonGroupControlled from "./ToggleButtonGroupControlled";
import { connect } from "react-redux";
import { fetchProbes } from "./store/action";
export class Buttons extends Component {
componentDidMount() {
this.props.fetchProbes();
}
render() {
let probes = null;
if (this.props.probes) {
probes = this.props.probes.map(probe => <li>{probe.title}</li>);
}
return (
<div>
<ToggleButtonGroupControlled />
<ul>{probes}</ul>
</div>
);
}
}
function mapStateToProps(state) {
return {
probes: state.probes
};
}
function mapDispatchToProps(dispatch) {
return {
fetchProbes: () => dispatch(fetchProbes())
};
}
export default connect(
mapStateToProps,
mapDispatchToProps
)(Buttons);
Finally, your toggle button component can properly dispatch a TOGGLE_FILTER action to your actions.js, which will filter the probes, then send the action to reducer, which will update your state and return the updated state, which at this point is mapped to your component props in your Button.js component.
import React, { useState } from "react";
import { ToggleButtonGroup } from "react-bootstrap";
import { ToggleButton } from "react-bootstrap";
import { connect } from "react-redux";
import { filterProbes } from "./store/action";
function ToggleButtonGroupControlled(props) {
const [value, setValue] = useState([1, 2]);
const toggleChangeHandler = newValue => {
setValue(newValue);
props.filterProbes(newValue);
};
return (
<ToggleButtonGroup
type="checkbox"
value={value}
onChange={e => toggleChangeHandler(e)}
>
<ToggleButton value={1}>PA Probes</ToggleButton>
<ToggleButton value={2}>Convential Probes</ToggleButton>
</ToggleButtonGroup>
);
}
function mapDispatchToProps(dispatch) {
return {
filterProbes: types => dispatch(filterProbes(types))
};
}
export default connect(
null,
mapDispatchToProps
)(ToggleButtonGroupControlled);
The cool thing about redux is that it allows for a global state, so you dispatch and change your list of probes from the ToggleButtonGroupControlled component, but that store (list of probes) it's also available for other components that you decide to connect to your store, in this case, Button.js.
You can check the final code running and ready for your problem here:
To understand more about redux-thunk, go here: https://github.com/reduxjs/redux-thunk
Also, there's a free redux book here that you could maybe take a quick look at: https://leanpub.com/redux-book
Redux might be overkill for this example, it all depends however at what level in the component hierarchy your table lives in relation to your ToggleButtonGroupControlled component.
It would help in your question to see the table component, is it in a separate file / route?
I would start simple and pass the value up out of your ToggleButtonGroupControlled component by creating an onChange prop. Right now your ToggleButtonGroupControlled component doesn't add much more functionality
than the third party ToggleButtonGroup component so it's a little hard to reason about.
Also if you do choose to go the redux route because you need this data in the global state then you can probably forego the local state you have here and select it from your redux store and pass into the component

Integrating Dispatch Actions in Container Component Pattern

So I'm completely confused on how to integrate the Container and Component Pattern. I've been reviewing examples all morning and nothing seems to be clicking. How I have been worked with React previously on my first project was fetch the data within my view components and then pass that data down as props using the #connect which works, but in an "automagically" way to me at this time.
import React;
...
import {action} from 'path/to/action.js';
#connect((store) => {return{ key: store.property}});
export class Component{
componentWillMount(){
this.props.dispatch(action());
}
}
As I'm working more with React I want to learn the more "correct" way of building out with Redux and understand on a deeper level what is happening.
What I have setup is
index.jsx (This renders all of my HOCs)
|
App.jsx (Container)
|
Auth.jsx (Component)
|
Layout.jsx (Component) - Contains app content
--or--
AuthError.jsx (Component) - 401 unauthenticated error page
Authentication is handled through an outside resource so this app will not control anything with Logging in or out. There will be no log in/out states simply receiving an object from an API that identifies the User Role & Authenticated Boolean.
What I would like to happen is when the App loads, it will fetch data from a mock API, JSON Server. From there it will render the Auth component. The Auth component will take in props from App.jsx and either render the Layout.jsx or AuthError.jsx.
Where I'm running into issues is how this should be integrated. I'm going to omit lines of code I don't think absolutely pertain to the question.
store.js
import { applyMiddleware, combineReducers, createStore } from 'redux';
import thunk from 'redux-thunk';
import { createLogger } from 'redux-logger';
import promise from 'redux-promise-middleware';
import { composeWithDevTools } from 'redux-devtools-extension';
import reducer from './reducers';
const middleware = applyMiddleware(promise(), thunk, createLogger());
export default createStore(reducer, composeWithDevTools(middleware));
index.jsx
import React from 'react';
import store from './store.js';
import ReactDOM from 'react-dom';
import { Provider } from 'react-redux';
import App from './containers/App.jsx';
ReactDOM.render(
<Provider store={store}>
<App />
</Provider>,
document.getElementById('root')
);
App.jsx
import React, { Component } from 'react';
import { connect } from 'react-redux';
import { bindActionCreators } from 'redux';
import { authenticateUser } from '../actions/authActions.js';
import Auth from '../components/Auth.jsx';
class App extends Component {
constructor(props) {
super(props);
this.state = {
authenticated: false // this needs to be set
};
}
componentWillMount() {
console.log('APP PROPS', this.props);
// this.props.actions.authenticateUser();
authenticateUser(); // this runs but doesn't run the dispatch function
// What I think needs to happen here Dispatch an Action and then setState referring back to how I would previous build with React Redux.
}
render() {
return (
<Auth app_name={ApplicationName} authenticated={this.state.authenticated} {...this.props} />
);
}
}
const mapStateToProps = state => {
console.log('redux store auth state', state);
return {
auth: state.auth
};
};
const mapDispatchToProps = dispatch => {
return { actions: bindActionCreators(authenticateUser, dispatch) };
};
export default connect(mapStateToProps, mapDispatchToProps)(App);
Auth.jsx
import React from 'react';
import { Route } from 'react-router-dom';
import AuthError from './AuthError.jsx';
import Layout from './Layout.jsx';
export default function Auth(props) {
console.log('AUTH PROPS', props);
const renderLayout = () => {
if (props.authenticated == true) {
return <Layout app_name={props.app_name} />;
} else {
return <AuthError />;
}
};
return <Route path="/" render={renderLayout} />;
}
authReducer.js
export default function reducer(
state = {
authenticated: null
},
action
) {
switch (action.type) {
case 'AUTH_SUCCESSFUL': {
return {
...state,
authenticated: action.payload.authenticated
};
break;
}
case 'AUTH_REJECTED': {
return {
...state,
authenticated: false
};
}
}
return state;
}
authActions.js
import axios from 'axios';
export function authenticateUser() {
console.log('authenticate user action has been called');
return function(dispatch) {
// nothing runs within this block so it's leading me to believe nothing is being `dispatch`ed
console.log('dispatch', dispatch);
axios
.get('localhost:3004/auth')
.then(response => {
dispatch({ type: 'AUTH_SUCCESSFUL', payload: response.data });
console.log('response', response);
})
.catch(err => {
dispatch({ type: 'AUTH_REJECTED', payload: err });
console.log('error', err);
});
};
}
Right now inside of App.jsx I can console the state of the authReducer and I can call authenticateUser() in my actions. But when I call authenticateUser() the return dispatch function doesn't run. Should I be dispatching the auth action in App.jsx? Or should I be dispatching the auth in Auth.jsx as a prop to then have App.jsx fetch the data? Just a bit lost on breaking this apart and what piece should be doing what work.
I'll do a brief explanation about it to help you to understand those patterns and don't get in confusion anymore (I hope).
So, let's forget reducers for a moment to focus on container, action creator and component pattern.
Component
A lot of people implement components by wrong way when using it with redux application.
A better component approach for redux is, implement it with stateless pattern (see Functional Components). Let's see in practice:
// components/Subscribe.js
import React from 'react'
import PropTypes from 'prop-types'
const Subscribe = ({text, confirmSubscription}) =>
<div>
<p>{text}</p>
<button onClick={confirmSubscription}>Confirm</button>
</div>
Subscribe.propTypes = {
subtitle: PropTypes.string.isRequired
}
Subscribe.defaultProps = {
subtitle: ''
}
export default Subtitle
This allows you to optimize component footprint because they have less features than stateful components (or class components), so you will win some performance and keep focused on component objective.
Container
In other hand, Container is a kind of component with some logical implementation. Container is a pattern created to bind React and Redux, because both should't interact directly. This means, a Container render the component, handle some component events (for example, form onSubmit) and feed components with application state. So, the Container is the best place to interact with Redux. (react-redux)[https://github.com/reactjs/react-redux] and Redux make this task a bit easier. So a simple Container to feed and capture interactions on Subscribe component could be like this:
// containers/SubscribeContainer.js
import React from 'react'
import PropTypes from 'prop-types'
import { bindActionCreators } from 'redux'
import { connect } from 'react-redux'
import { confirmSubscription } from 'actions/subscription'
import Subscribe from 'components/Subscribe'
const mapStateToProps = state => ({
text: state.subscription.text
})
const mapDispatchToProps = dispatch =>
bindActionCreators({
confirmSubscription
}, dispatch)
const Container = connect(mapStateToProps, mapDispatchToProps)
export default Container(Subscribe)
Action Creator
An action creator (or action creators), is just a collection of or a function where return an action. Simple like that:
// actions/subscription
export const CONFIRM_SUBSCRIPTION = 'actions.confirmSubscription'
export function confirmSubscription() {
return {
type: CONFIRM_SUBSCRIPTION
}
}
For now, we have the triad pattern, Component, Container and Action Creator implemented, from here, you just need two more things to make this working with Redux.
Create a subscription store.
Handle CONFIRM_SUBSCRIPTION (in case to update app's state)
Return a new state
The magic will happen when you return a new state from any reducer, the mapStateToProps will be called and you will receive the new state as argument and from there, React will update your components when necessary, in case of those components are stateless, PureComponent (works only with single level states and props) or custom shouldComponentUpdate.
Another thing to keep on mind is to not do fetch or async execution inside Components, Containers and Action Creators, instead, you can use middleware like redux-thunk to compose a custom middeware to capture actions and handle that before be sent to reducers.
your authenticateUser returns a function, you need to literally run the function. The right way to do that is to add a property in your mapDispatchToProps
const mapDispatchToProps = dispatch => {
return { authenticateUser: () => dispatch(authenticateUser()) };
};
Then, in your componentWillMount function, call
this.props.authenticateUer()
Check this

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