DWE

  BASIC OF REDUX: ##### Create a project with react. Then, 1) npm run start 2) npm install redux react-redux 3) create actions folder inside src folder. Create index.js file inside actions folder. 4) create reducers folder inside src folder and create upDown.js file inside reducers folder. 5) create store.js file inside src folder. 6) In app.js write: ``` import React from 'react' import "./App.css" const App = () => {   return (     <>       <div className="container">         <h1>Increment / Decrement counter</h1>         <h4>Using react and redux</h4>         <div className="quantity">           <a className="quantity__minus" title='Decrement'><span>-</span></a>           <input type="text" name='quantity' className='quantity__input'/>         ...

 Try the following code in terminal of project folder:  npx clear-npx-cache Then, run:  npx create-react-app projectname

 This error occurs as because may be you have used the following code:  const MongoStore= require('connect-mongo')(session); and app . use ( session ({     secret : ' keyboard cat ' ,     resave : false ,     saveUninitialized : false ,     store: new MongoStore({ mongooseConnection: mongoose.connection }) })); Now this is happening as because syntax have been changed (see the documentation here: documentation ) Solution that worked for me:  Use this:  const MongoStore = require ( ' connect-mongo ' ); and,  app . use ( session ({     secret : ' keyboard cat ' ,     resave : false ,     saveUninitialized : false , //false means don't create a session untitl it is stored     // store: new MongoStore({ mongooseConnection: mongoose.connection })     store : MongoStore . create ({         mongoUrl : process.env. MONGO_URI     }) }));

 Write: app . engine ( ' .hbs ' , exphbs. engine ({ defaultLayout : ' main ' , extname : ' .hbs ' })); Instead of  app . engine ( ' .hbs ' , exphbs({ defaultLayout : ' main ' , extname : ' .hbs ' }));

  In the root directory: mkdir backend cd backend then type: npm init -y npm install express cors mongodb dotenv npm install -g nodemon write the following line in package.json after "main":"index.js" : "type":"module", Now, create server.js file inside backend folder. Write the following code in server.js file: // starts here import express from "express"; import cors from "cors" import restaurants from "./api/restaurants.route.js" const app = express(); app.use(cors()); app.use(express.json()); app.use("/api/v1/restaurants", restaurants); app.use("*",(req,res) => res.status(404).json({error: "Not found!"}) ); export default app; // ends here create .env file and write: RESTREVIEWS_DB_URI=mongodb+srv://ipritpritam:ipritpritam@cluster0.twcdr.mongodb.net/sample_restaurants?retryWrites=true&w=majority RESTREVIEWS_NS=sample_restaurants PORT=5000 then, create index.js in the backend ...

  Type 'powershell' in the command prompt and open by clicking 'run as administrator' and type the following command: Set-ExecutionPolicy RemoteSigned -Scope CurrentUser and press Y for yes That's it. Hopefully this will work.