deal with all error cases when getting an url

[bernhardreiter]

According to https://developer.mozilla.org/en-US/docs/Web/API/fetch we need to deal with exceptions and with different response codes in case response.ok == false.

Dot get done in lib/urloader.ts

[ThomasJunk]

This may be not possible:

• Chrome having a general error.message of Failed to fetch
• Firefox having a general error.message of NetworkError when attempting to fetch resource.

which both does not allow to differentiate further although the documentation suggests otherwise.

Having looked at Stack Overflow I found this:

As a client of fetch, you can't differentiate network errors from other errors caused by building an incorrect request, as both are thrown as TypeErrors. (See https://developer.mozilla.org/en-US/docs/Web/API/fetch#exceptions). This is quite a flaw, as application defects that cause an incorrectly built request may go unnoticed, masked as if they were circumstantial network errors.

Which basically says the same I experienced. So I leave a "general" error handler for these cases. But otherwise implemented messages distinguishing between the typical 401, 403, 404.

[bernhardreiter]

Meanwhile improved by @ThomasJunk by dealing with response code. @JanHoefelmeyer did you test that other error message work already?

[JanHoefelmeyer]

Error-responses will be handled as expected:

An error will cause an error Text to appear, detailing the status code and statustext (if any).