Azure random 404 on valid URL in Application Insights

Question

My website uses AngularJS (v1) with webapi. I have a file upload directive that posts to my file upload controller. On some calls to the file upload, I get a 404 not found on a valid address. Most of the time it works as expected. If I look through the Application Insights on Azure, I can see some weird reporting in regards to the file upload api. See images

In the first image in the left column, I can see 8 errors reported with a POST to /api/fileupload/upload. Middle column shows all 8 are 404s, and in the third column, I can see the request URL, which if I copy and paste into the browser, doesn't return a 404 (returns a 405, method not allowed which I'd expect as it doesn't support GET requests but it does find the url).

The second image shows a valid api request (this error is expected). The left column shows a POST to fileupload/upload (NOT /api/fileupload/upload/ as in the first image that 404s), but the middle and left columns show the same request URL as the 404 in the first image.

In angular, I only call the API from one spot in my file upload directive:

angular.element($element).fileupload({
    url: 'api/fileupload/upload/',
    type: 'POST',
    ...
    ...
});

What are these 404s? How can I stop them? How can I find out where its going wrong?

score 0 · Accepted Answer · edited May 23 '17 at 10:30

0

Regarding calls to upload resulting in 404: it is a known issue that ASP.NET can return 404s when attempting to upload files that exceed allowed size. See here for more details.
Regarding the error on your second image, it is unclear from your question, whether these are expected, or not, but to note - this is 400, not 404 and 400s can be thrown for invalid routing.

edited May 23 '17 at 10:30

Community

1
1

answered Mar 20 '17 at 05:36

Alex Bulankou

2,396
19
21

The 400 is expected behavior, I return a 400 if a bad file type is detected (such as exe). I am meaning that in the second screenshot the URL is found (not 404'ing). I will test this and see if I can reproduce the behaviour. Thanks. – garethb Mar 20 '17 at 06:12

Azure random 404 on valid URL in Application Insights

1 Answers1