Fetch doesn't return 404 status

Hi Guys,

I have the following code:

   fetch('http://asfklajsdflkajsdfkj.com/test', {
	    method: 'POST',
	    headers: { "Content-type": "application/x-www-form-urlencoded; charset=UTF-8"},
	    body: "InpNumber=" + InpNumber.value
	}).then(function(response) {
	    var status = response.status;  // Get the HTTP status code
	    var response_ok = response.ok; // Is response.status in the 200-range?
	    return response.json();    // This returns a promise
	}).then(function(response) {
		if(response.result == 'success'){
			ActivationID = response.data.validation;
			setState(3, null);
		} else {
			setState(2, response.error);
	}).catch(function(err) {
		setState(2, "An error has occurred");

I have put in a random URL in the fetch parameters as shown to simulate what it would be like if there was a server down or not found. For some reason fetch doesn’t return any response when there is a 404 error or throw an error that is caught. Any ideas on how to catch 404 error?

i think, that it will be more issues with “fetch” … https://www.fusetools.com/community/forums/howto_discussions/typeerror_network_request_failed_on_https

A random generated URL is a very bad test-case since you never know what you will hit. In the case above you try to target a domain that does not exists. So the server can not reply with any errors at all. So you don’t get any answer. 404 is a response you get when a client has entered an URL that the server does not understand, hence you need to have communication with the server first.

Good point Anders - but how do I detect if the Fetch cannot find any server??

For example, my servers crash or my domain expires, how does the app detect that fetch is failing?

After testing I can see that we are not throwing any exception. That could be because the timeout is very long, but I’m not sure. I’ve raised an internal issue to investigate.

Thank you.

While investigating could you please provide an update on when FormData will be made available for use - so photos/videos can be easily uploaded.

And if there is any plans to support a fetch cancel function/method.


I can’t say when FormData will be available because we have a lot of other high pri tickets on HTTP that needs to be done first. But we do have it on the list.

Fetch cancel: Yes, that is indeed something we want. But as you can see from the whatwg issue 27 this is a very complex problem. We are following the effort here that we hope will end up as a general solution we can depend on.

If you need something like timeout or cancel, you could use setTimeout or use XMLHttpRequest.abort().