Axios Network Error depending on CORS policy in Node JS-CodePudding

While trying to carry out put axios request the following error occurs:

The CORS module was installed and switched in server.js file, but seems that doesn't work. By the way there are no any CORS headers in the request:

So in server.js file the CORS module is implemented. I tried to add {origin: "http://localhost:3000"} in brackets but that didn't work. The brackets are empty.

server.js:

const express = require("express");
const mongoose = require("mongoose");
const apiRoutes = require('./routes/apiRoutes');
const path = require('path');
const cors = require("cors")
require("dotenv").config();

const app = express();
const PORT = 3001;
app.use(cors());
app.use(express.static(path.join(__dirname, 'images')));
app.use(express.urlencoded({ extended: false }));
app.use(express.json());
app.use(apiRoutes);

mongoose
    .connect(process.env.MONGO_URL)
    .then(res => console.log("The connection to the Database was carried out successfully."))
    .catch(error => console.log(`The Error while connecting to the Database occured: ${error.message}`))
    
app.listen(PORT, 'localhost', error =>
    console.log(error ? `The Error occured: ${error.message}.` : `The Listening Port is ${PORT}`)
);

the route:

router.put("/api/newAd/:creationDate", (req, res) => {
  console.log(req.body);
  // Ad.updateOne({ creationDate: req.body.creationDate }, {
  //   textInfo: req.body
  // })
})

the client side:

    const saveAndPlace = () => {
        axios.put(`/api/newAd/${creationDate}`)
        .catch(err => console.log("error", err))
    };

So why these errors occur? And why the headers are not shown in the network panel?

CodePudding user response：

The error message says nothing about CORS. The URL and the Referer have the same origin so it isn't even a cross-origin request!

What it does says is "Blocked by Client" on a URL with "Ad" in it which strongly suggests that the problem is an ad-blocking extension extension installed in the browser.