Connect node.js PostgreSQL database and Vue client locally - node.js

Question

New to all of this so this might be the wrong setup. I have set up one project which uses node to connect to a postgreSQL. This works and I can start this from VS Code using:
node index.js
and the response is:
App running on port 3000.
Another project is a client and has been created Vue. This is started using
npm run serve
The response is:
App running at:
- Local: http://localhost:8080/
The Vue client gets data from a source using the code below and then displays it. In this example it uses some dummy data and works fine.
created: function () {
axios
.get('https://jsonplaceholder.typicode.com/users/')
.then(res => {
this.users = res.data;
})
}
However if I change the source above to communicate with the local postgreSQL database server:
.get('http://localhost:3000/users/')
I quite rightly get the security issue in the browser console when trying to connect:
Cross-Origin Request Blocked: The Same Origin Policy disallows reading
the remote resource at http://localhost:3000/users/. (Reason: CORS
header 'Access-Control-Allow-Origin' missing)
So how do I intergrate the node.js part and the vue client part?
UPDATE
The answer to the question is below but I changed very slightly. The following was added to the index.js file (the node postgreSQL part). It is importing cors and saying allow conneciton from localhost:8080. Works perfectly:
import cors from 'cors';
const corsOptions = {
origin: 'http://localhost:8080'
};

Answer 1

You have to install lib cors. For that in your project folder just run the command:
npm i --save cors
After that lib is installed you should import and configure in your server application. To enable your front-end communicate with server side application.
const express = require('express');
const logger = require('morgan');
const cors = require('cors'); //<--install this lib
const app = express();
cors({ credentials: true, origin: true });//enable some headers for handling authentication tokens
app.use(cors());//use in your server
app.use(express.json());
if (process.env.NODE_ENV !== 'test') { app.use(logger('dev')); }
app.use(require('./server/index'));
module.exports = app;
As stated by the documentation, when you use the function cors() its equivallent to:
{
"origin": "*",
"methods": "GET,HEAD,PUT,PATCH,POST,DELETE",
"preflightContinue": false,
"optionsSuccessStatus": 204
}