- From: tlhackque <tlhackque@yahoo.com>
- Date: Mon, 10 Feb 2014 07:30:55 -0500
- To: public-webapps@w3.org
I found myself using XMLHttpRequest in an application where, when things go wrong, I wanted to provide information to the user. I was unable to do so. Specifically, I POSTed a form with a large file, and specified listeners for abort and error events (among others) on both the request and upload targets. I tried disconnecting the network, shutting down the target webserver, mis-spelling the host name, having the server refuse service and injecting various other real-world misadventures. Although I get the events in several browsers, nothing in the event tells me what went wrong. And I find nothing in the specification ( http://dvcs.w3.org/hg/xhr/raw-file/tip/Overview.html - 22-Nov-2013) to help. According to the spec, in the synchronous model, the exception would at least specify 'NetworkError'. Async, the only thing one gets is the event type, bytes transfered, and (possibly) total bytes. One can assume if loaded is zero, no connection was established; otherwise there was a connection failure, but that's about it. It really would be useful - both for debugging and for providing feedback to users - if the error and abort events provided some detail: Was the problem: DNS failure: no server, host has no A(AAAA) record? Proxy not reachable? Host not reachable? SSL certificate expired? Connection broken? Aborted by user action? Aborted by object destruction? Some supporting detail (e.g. IP address of peer, proxy, etc) would be helpful too. This is not intended to be an exhaustive list. While I would discourage client scripts from trying to analyze OS-specific error codes, some user-actionable clues would be really helpful. 'An error occurred sending <flilename>' is about the best one can do currently, and that doesn't give the user - or the helpdesk - much to go on! Please consider updating the spec to provide reasonable diagnostics for network error events. -- This communication may not represent my employer's views, if any, on the matters discussed.
Received on Monday, 10 February 2014 14:26:38 UTC