Any Apache server (not Tomcat) can handle the '?' and '??' cases with a
few rewrite rules to transform them into typical CGI-like query strings.

   # Detect ? and ?? inflections and map to typical CGI-style parameters.
   # One question mark case:  ?  -> ?show=brief&as=anvl/erc
   RewriteCond %{THE_REQUEST}  \?
   RewriteCond %{QUERY_STRING} ^$
   RewriteRule ^(.*)$ "$1?show=brief&as=anvl/erc"

   # Two question mark case:  ?? -> ?show=support&as=anvl/erc
   RewriteCond %{QUERY_STRING} ^\?$
   RewriteRule ^(.*)$ "$1?show=support&as=anvl/erc"

So if your architecture supports query strings of the form

   ?name1=value1&name2=value2&...

it can support ARK inflections.

> I don't believe that the ARK spec and HTTP URIs are fully compatible ideas.

True.  A '?' by itself has no meaning in the URI spec, which means it's
also an opportunity to do something intuitive and important with an
unused portion of the "instruction space" (of strings that start out
looking like URLs).  Any URLs (not just ARKs) could support this.

The THUMP spec (where inflections really live) will be modified to
require an extra HTTP response header to indicate that the server is
responding to an inflection and not to a standard URI query string.
This could help in the '??' case, which actually could be interpreted
as a valid URI query string.

-John


--- On Mon, 8 Dec 2014, Ethan Gruber wrote:
> Thanks for the info. I'm glad I'm not the only person struggling with this.
> I'm not entirely sure my architecture will allow me to append question
> marks in this way (two question marks is probably feasible, but it doesn't
> appear that one is). I don't believe that the ARK spec and HTTP URIs are
> fully compatible ideas. Hopefully some clearer request parameter or content
> negotiation standards emerge.
>
> Ethan
>
> On Sat, Dec 6, 2014 at 10:23 AM, Phillips, Mark <[log in to unmask]>
> wrote:
>
>> Ethan,
>>
>> As Mark mentioned we have implemented the ARK inflections of ? and ?? with
>> our systems.
>>
>> I remember the single ? being a bit of a problem to implement in our
>> system stack (Apache/mod_python/Django) and from what I can tell isn't
>> possible with (Apache/mod_wsgi/Django) at all.
>>
>> The ?? inflection wasn't really a problem for us on either of the systems.
>>
>> From conversations I've had with implementors of ARK,  the issues around
>> supporting the ? and ?? inflections don't seem to be related to the
>> frameworks issues as other issues like commitment to identifiers, the fact
>> that ARKs are being used in a redirection based system like Handles, or the
>> challenges of accessing the item metadata for items elsewhere in their
>> system.
>>
>> I think having a standard set of request parameters or other url
>> conventions could be beneficial to the implementation of these features by
>> others.
>>
>> Mark
>> ________________________________________
>> From: Code for Libraries <[log in to unmask]> on behalf of
>> [log in to unmask] <[log in to unmask]>
>> Sent: Saturday, December 6, 2014 8:23 AM
>> To: [log in to unmask]
>> Subject: Re: [CODE4LIB] Functional Archival Resource Keys
>>
>> This brief exchange on Twitter seems relevant:
>>
>> https://twitter.com/abrennr/status/296948733147508737
>>
>> On Fri, Dec 5, 2014 at 12:50 PM, Mark A. Matienzo <[log in to unmask]
>>>
>> wrote:
>>
>>> Hi Ethan,
>>>
>>> I'm hoping Mark Phillips or one of his colleagues from UNT will respond,
>>> but they have implemented ARK inflections. For example, compare:
>>>
>>> http://texashistory.unt.edu/ark:/67531/metapth5828/
>>> http://texashistory.unt.edu/ark:/67531/metapth5828/?
>>> http://texashistory.unt.edu/ark:/67531/metapth5828/??
>>>
>>> In particular, the challenges posed by inflections are described in this
>>> DC2014 paper [0] by Sébastien Peyrard and Jean-Philippe Tramoni from the
>>> BNF and John A. Kunze from CDL.
>>>
>>> [0] http://dcpapers.dublincore.org/pubs/article/view/3704/1927
>>>
>>> Cheers,
>>> Mark
>>>
>>>
>>> --
>>> Mark A. Matienzo <[log in to unmask]>
>>> Director of Technology, Digital Public Library of America
>>>
>>> On Fri, Dec 5, 2014 at 2:36 PM, Ethan Gruber <[log in to unmask]> wrote:
>>>
>>>> I was recently reading the wikipedia article for Archival Resource Keys
>>>> (ARKs, http://en.wikipedia.org/wiki/Archival_Resource_Key), and there
>>> was
>>>> a
>>>> bit of functionality that a resource is supposed to deliver that we
>> don't
>>>> in our system, nor do any other systems that I've seen that implement
>> ARK
>>>> URIs.
>>>>
>>>> From the article:
>>>>
>>>> "An ARK contains the label *ark:* after the URL's hostname, which sets
>>> the
>>>> expectation that, when submitted to a web browser, the URL terminated
>> by
>>>> '?' returns a brief metadata record, and the URL terminated by '??'
>>> returns
>>>> metadata that includes a commitment statement from the current service
>>>> provider."
>>>>
>>>> Looking at the official documentation (
>>>> https://confluence.ucop.edu/display/Curation/ARK), they provided an
>>>> example
>>>> of http://ark.cdlib.org/ark:/13030/tf5p30086k? which is supposed to
>>> return
>>>> something called an Electronic Resource Citation, but it doesn't work.
>>>> Probably because, and correct me if I'm wrong, using question marks in
>> a
>>>> URL in this way doesn't really work in HTTP.
>>>>
>>>> So, has anyone successfully implemented this? Is it even worth it? I'm
>>> not
>>>> sure I can even implement this in my own architecture.
>>>>
>>>> Maybe it would be better to recommend a standard set of request
>>> parameters
>>>> that actually work in REST?
>>>>
>>>> Ethan
>>>>
>>>
>>
>>
>>
>> --
>> Tod Robbins
>> Digital Asset Manager, MLIS
>> todrobbins.com | @todrobbins <http://www.twitter.com/#!/todrobbins>
>>
>