Access the HTTP response headers via JavaScript

[sproket]

Hi all,

I was wondering if there is any specification or discussion on allowing JavaScript to access the HTTP headers in the response sent from the server.

It seems you can do this by sending a separate head request with XMLHttpRequest, however that means making another trip to the server.

If the server sends back arbitrary HTTP headers there seems to be no way of reading these.

Thoughts?

TIA

[JAB Creations]

Welcome to the forums Tia.

Unfortunately it seems that is not a supported feature after quickly going though the ECMAScript 5.1 specifications...
http://ecma-international.org/ecma-262/5.1/

It seems like at this moment in time you'll have to use XMLHttpRequest like so...

Code: Select all

//var url = 'http://www.example.com/';
var x = new XMLHttpRequest();
x.open('GET', url, false);
x.send(null);
var h = x.getAllResponseHeaders();
alert(h);

[zcorpan]

Hi all,

I was wondering if there is any specification or discussion on allowing JavaScript to access the HTTP headers in the response sent from the server.

It seems you can do this by sending a separate head request with XMLHttpRequest, however that means making another trip to the server.

Right, there's no way to do that. The server can repeat the headers in the response body in an HTML comment or as a JSON blob in a <script> block or whatever, though.

If the server sends back arbitrary HTTP headers there seems to be no way of reading these.

What's the use case?