mern.stack.commands.txt

>>>>>>>>> M E R N Stack <<<<<<<<<<<


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M - MongoDB
E - Express js
R - React js
N - Node js
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//When request is sent from frontend (React) showing errors or "CORS"
//(Reason: CORS header ‘Access-Control-Allow-Origin’ missing).

//Fixed: Install cors in express js and paste code given blow in express js (Backend)
  npm i cors express nodemon

  app.use(function(req, res, next) {
  res.header("Access-Control-Allow-Origin", "*");
  res.header("Access-Control-Allow-Credentials", "true");
  res.header("Access-Control-Allow-Headers", "Origin,Content-Type,   Authorization, x-id, Content-Length, X-Requested-With");
  res.header("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS");
  next();
  });


//In express js : Used This code to respone to frontend

reating a simple Express GET request

Below is a simple index.js express server.

const express = require('express');
const app = express();

    const ingredients = [
    {
        "id": "1",
        "item": "Bacon"
    },
    {
        "id": "2",
        "item": "Eggs"
    },
    {
        "id": "3",
        "item": "Milk"
    },
    {
        "id": "4",
        "item": "Butter"
    }
];

app.get('/ingredients', (req, res) =>{
    res.send(ingredients);
});
app.listen(6069);
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