Indicating XHR conformance

I'm wondering if it would be useful to have some optional flags in  
implementations that developers can use to test for. While many JS  
features can be tested for by testing a property, this isn't so for  
XHR; e.g., you can't easily test to see if it supports more than GET  
and POST, for example, or if the cache is correctly implemented.

For example, we could specify a tree of properties on the navigator  
object that are tied to passing the test suite; authors could use  
that to figure out if certain features are supported. E.g.,

navigator.w3c.xhr.full  // passes the full test suite
navigator.w3c.xhr.core // passes all of the MUST-level requirements  
in XHR
navigator.w3c.xhr.cache // passes all HTTP caching-related tests
navigator.w3c.xhr.redirect // passes all HTTP redirect-related tests

There are many ways that this could be done, of course; that's just  
an example.

The biggest downside I can see is that a vendor might not correctly  
set them (through accident or maliciously). However, even in that  
case, it's a lot easier for authors to test for the property and then  
make an exception or two, rather than test every browser and maintain  
a whitelist in code.

--
Mark Nottingham
mnot@yahoo-inc.com

Received on Wednesday, 10 May 2006 15:31:00 UTC