W3C home > Mailing lists > Public > public-iri@w3.org > May 2011

Re: Non-hierarchical base URLs (was Re: draft-abarth-url-01 uploaded)

From: Julian Reschke <julian.reschke@gmx.de>
Date: Tue, 03 May 2011 10:50:16 +0200
Message-ID: <4DBFC1C8.8050901@gmx.de>
To: Maciej Stachowiak <mjs@apple.com>
CC: "Roy T. Fielding" <fielding@gbiv.com>, Adam Barth <ietf@adambarth.com>, public-iri@w3.org
On 03.05.2011 04:55, Maciej Stachowiak wrote:
>
> On May 2, 2011, at 7:24 PM, Roy T. Fielding wrote:
>
>> On May 2, 2011, at 6:26 PM, Adam Barth wrote:
>>
>>> On Mon, May 2, 2011 at 6:24 PM, Roy T. Fielding<fielding@gbiv.com>  wrote:
>>>> On May 2, 2011, at 5:42 PM, Adam Barth wrote:
>>>>> You're missing the constraint that browser vendors aren't going to
>>>>> change their implementations to align with this dream.
>>>>
>>>> There is no such constraint.  Real browser developers like to fix
>>>> bugs when they are found, particularly when it makes their behavior
>>>> more interoperable with existing content.
>>>
>>> Perhaps you missed this message:
>>>
>>> On Mon, Apr 25, 2011 at 1:38 AM, Maciej Stachowiak<mjs@apple.com>  wrote:
>>>> On Apr 25, 2011, at 1:27 AM, Julian Reschke wrote:
>>>>> Actually, Safari *does* the right thing here.
>>>>
>>>> Safari has serious bugs as a result of doing the RFC-compliant thing here. We plan to change to be more like other browsers.
>>>>
>>>> Regards,
>>>> Maciej
>>>
>>> AFAIK, Maciej is about as "real" a browser developer as they come.
>>
>> AFAICT, Maciej based that statement on memory instead of an actual
>> use case or test, since Safari does parse URIs correctly and so does
>> Firefox.  When we come up with an example that is "more like other
>> browsers" and is still broken, then we can talk about how to fix it.
>>
>> And when we do, all implementations will be taken into consideration.
>
> The specific context of my statement is bugs I looked at fairly recently, but which unfortunately i cannot explain in detail because some of them have serious security consequences and they are as yet unpatched.
>
> In the course of working on some of these bugs, I came to the conclusion that Safari should abandon scheme-independent URL parsing, as most other browsers hardcode knowledge of certain schemes as hierarchical and this seems to result in better real-world compatibility,
>
> I am skeptical of the example where a data: URI is the base URI for a relative reference; while the behavior for this must defined one way or another, I would not expect there to be Web content that depends on a specific choice of behavior here, because (a) data: URLs are rare on the Web; and (b) there's almost nothing sensible you can do in this case. Note that Adam just used<base>  for convenience, the example could just as well have been written as an actual data: URL which would then act as the anchor for URLs inside the body. But there are more realistic cases where a relative URL may be resolved against a base of a non-hierarchical URI scheme, e.g.:
>
> <iframe id=foo src="about://blank" onload="test()"></iframe>
> <script>
> var doc = document.getElementById("foo").contentDocument;
> var anchor = doc.createElement("a");
> anchor.setAttribute("href", "foo.html")
> doc.body.appendChild(anchor);
> alert(anchor.href);
> </script>
> ...

FF4: resolves against the document's URI (not about://blank)
IE9: doesn't load the iframe
Opera: as FF4
Chrome: alert shows nothing
Safari: resolves against the about URI

So, again, no interop whatsoever.

Best regards, Julian
Received on Tuesday, 3 May 2011 08:51:02 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 30 April 2012 19:52:01 GMT