Get rid of a 401 (unauthorized) ajax error in browser console

Question

I'm calling an api through javascript using a jQuery.ajax call. The api respond with 401 if the user is not authenticated and I want to ignore this error only for this call.

I've tried all the callback options described in the jQuery options but the error still pops out in the browser console (both in Firefox and Chrome).

Here is a sample code which trigger the error:

$.ajax({
    type: 'GET',
    url: '/url-with-auth',
    dataType: 'json',
    statusCode: {
        401: function (error) {
            // simply ignore this error
            console.log(error);
        }
    },
    complete: logall,
    error: function () {
        // simply ignore this error
        console.log(error);
    },
    async: false
}).fail(function () {
        // ignore the error and do nothing else
        console.log("$.get failed!");
    });

This also has the side effect of requesting again the user credentials on a staging machine which is protected by an .htaccess file since the browser thinks that the user is not authenticated, so in following requests the user needs to reenter his http credentials.

Is there any way to completely ignore this error?

Edit

Currently I have an HTML template which is entirely cached application side and I want to keep this behavior for performance reasons. The only part which changes in the layout is the login informations for the current user, so I'm rendering the (cached) page with the default markup for not logged in users and then using jQuery I replace the relevant elements of the markup with the login informations returned by an ajax call. So if the user is not logged and the ajax endpoint return 401 I don't need anything, the markup should remain the same.

Everything is working at this moment, the only ugly thing is that I have that 401 javascript error in the console and I'd like to get rid of it.

Here is a screenshot of the message I'm talking about:

Answer 1

I also ran into this issue and wanted to surpress the exception in the JavaScript console for HTTP 401 and 404 etc errors. I found this question and didn't see why the error() and statusCode() handlers didn't quiet the exception so i did my own digging into it.

As far as i can tell it turns out that this is an issue with the native ajax XMLHttpRequest Object in the browser, not with jQuery. To prove this i used the following test code:

function xhrTest(index) {
    var ajaxObjects = [
        $.ajaxSettings.xhr(), // what jquery returns
        new XMLHttpRequest()  // the native one in the browser
    ];
    var ajax = ajaxObjects[index];
    ajax.onreadystatechange = function() {console.log("xhrTest: state: " + ajax.readyState)};
    var errorHandler = function() {console.log("xhrTest: error");};
    ajax.onerror = errorHandler;
    ajax.onabort = errorHandler;
    ajax.open("GET", "/fileThatDoesNotExist", true);
    ajax.send();    
}

Note that when calling this (i did it from the JavaScript console) with either xhrTest(0) or xhrTest(1), which bypasses jQuery, that the results are the same: