Re: Working Group Decision on ISSUE-120 rdfa-prefixes

On 03/29/2011 01:36 PM, Tab Atkins Jr. wrote:
> Based on some private correspondence, please consider this to be a
> Formal Objection.

Recorded:

http://dev.w3.org/html5/status/formal-objection-status.html#ISSUE-120

- Sam Ruby

> On Tue, Mar 29, 2011 at 8:53 AM, Tab Atkins Jr.<jackalmage@gmail.com>  wrote:
>> On Tue, Mar 29, 2011 at 7:59 AM, Sam Ruby<rubys@intertwingly.net>  wrote:
>>> === Arguments not considered:
>>>
>>> Following are either direct quotes or paraphrases of arguments which
>>> were put forward which were not considered.
>>>
>>>   Running examples from the OpenGraph Protocol site through the
>>>   facebook linter shows that removing the prefix declaration has no
>>>   effect but changing it prevents any properties from being recognised.
>>>   Code inspection of some of the other tools indicates that there are
>>>   clients in Python, PHP, Ruby and Java that depend on literal matching
>>>   of the string "og:".
>>>
>>> No change proposal was put forward suggesting that all usages be
>>> migrated to fixed prefixes.  Nor was there any evidence put forward
>>> that fixes to these tools would break content.  The fact that these
>>> tools have bugs is uncontested but that, in itself, does not help
>>> identify the proposal that draws the weakest objections.
>> ...
>>>   It would be important to know if Facebook's and Google's content
>>>   consuming code could be made work with prebound prefixes for
>>>   compatibility with legacy content that uses prefixes.
>>>
>>> We only consider proposals which actually were put forward.  Neither
>>> change proposal proposed standardizing Facebook's or Google's prefixes.
>>
>> I object to these two arguments not being considered, as they are
>> directly relevant to the "we already have legacy content using
>> prefixes" argument, which was considered to be the strongest argument
>> and thus in need of disproving.
>>
>> If a large fraction of the legacy processing tools do *not* recognize
>> the prefix mechanism, but instead rely on fixed prefixes (that is,
>> just specially-qualified names), then that is strong evidence that
>> prefixes are too complicated, as multiple tools get them completely
>> wrong.
>>
>> Further, if, as a result of multiple tools actually recognizing
>> specially-qualified names instead of names with namespace prefixes, a
>> significant percentage of authored content contains "invalid" RDFa
>> with wrong or missing prefix declarations, that is also strong
>> evidence that prefixes are too complicated, and further, it is strong
>> evidence that the "legacy content" does *not* actually use the prefix
>> mechanism, but instead uses another mechanism to specially-qualify the
>> names (generally, fixed prefixes) which is invalid according to RDFa
>> and which would *fail* to be processed in conformant RDFa processors.
>>
>> That last bit is very important.  If we must have RDFa, then I
>> strongly object to any decision which pushes us down the RSS path
>> where no processor is conformant, and the successful processors must
>> use expensive reverse engineering to find the union of non-conformant
>> behaviors which successfully process an appropriately large fraction
>> of legacy content.  We're already walking this road, but we change
>> course with appropriate action now.
>>
>> ~TJ
>

Received on Tuesday, 29 March 2011 17:57:59 UTC