Missing headers in Fetch response

Question

I need to make a CORS post request. I need to use fetch because axios's response is already processed to json.

But in fetch response, the headers is empty. But I don't think this is the server problem since axios response headers have the values that I want.

Any trick?

    fetch('http://localhost:9876/test/sample-download', {         method: 'post',         headers: {},         body: {}     })         .then(response => {             console.log(response);         })         .catch(err => console.error(err));      axios.post('http://localhost:9876/test/sample-download', {}, {})         .then(response => console.log(response))         .catch(error => console.error(error)); 

Answer 1

Headers are limited for CORS requests. See https://stackoverflow.com/a/44816592/2047472

(Use access-control-expose-headers to allow exposing headers to requests from a different origin.)

Answer 2

The Headers class instance that fetch returns is an iterable, as opposed to a plain object like axios returns. Some iterable's data, such as Headers or URLSearchParams, aren't viewable from the console, you have to iterate it and console.log each element, like:

fetch('http://localhost:9876/test/sample-download', {     method: 'post',     headers: {},     body: {} }) .then(response => {   // Inspect the headers in the response   response.headers.forEach(console.log);   // OR you can do this   for(let entry of response.headers.entries()) {     console.log(entry);   } }) .catch(err => console.error(err));