Re: redirects and relative URLs

On 29 Jan 2012, at 14:29, Melvin Carvalho wrote:

> On 29 January 2012 14:12, Henry Story <henry.story@gmail.com> wrote:
>> 
>> On 29 Jan 2012, at 14:03, John Erickson wrote:
>> 
>>> Henry asked:
>>>> If I dereference a URL which contains a redirect to another resource, and that
>>>> resource contains relative URLs, how should the relative URLs of the returned
>>>> document be completed? With the initial URL? Or with the one given in the Location
>>>> header (or some other header?) of the last document?
>>>> 
>>>> Perhaps this has been written up somewhere?
>>> 
>>> Doesn't RFC 3986 <http://www.ietf.org/rfc/rfc3986.txt> speak to this?
>>> 
>>> 5.1.3.  Base URI from the Retrieval URI
>>> 
>>> If no base URI is embedded and the representation is not encapsulated
>>> within some other entity, then, if a URI was used to retrieve the
>>> representation, that URI shall be considered the base URI.  Note that
>>> if the retrieval was the result of a redirected request, the last URI
>>> used (i.e., the URI that resulted in the actual retrieval of the
>>> representation) is the base URI.
>> 
>> Thanks John,
>> 
>>   that is really important. It is easy to get this wrong. Some tools like
>> Apache's HTTP client do such a good job at redirecting that it is easy to
>> miss this.
>> 
>> Here is the HTTP version of the RFC.
>> 
>>   http://tools.ietf.org/html/rfc3986#section-5.1.3
>> 
>> Just forwarding this to WebID Community Group [1], as of course this is
>> very important there, since it would make a big difference as to what is
>> considered the WebID finally.
> 
> A WebID is a simply URI that represents a person.

You mean "a WebID _refers_to_ a Person". A representation is 
something very different. It is a document, that contains 
things like URLs.

> Important not to confuse what a WebID is, with any particular
> verification pattern.

It does not matter what the verification pattern is. If the WebID appears
in a document which has relative URLs and you need to know what WebIDs 
these relative URLs _resolve_to_,  to use language from RFC3986, you need
among other things to know what the HTTP Location headers said. Information
inside the document can make a difference too, but all rdf parsers know about
that.

Henry


> 
>> 
>> 
>>  Henry
>> 
>> PS. The WebID Incubator Group just switched to a community Group
>>    http://www.w3.org/community/webid/
>>  Please feel free to join the community!
>> 
>>> 
>>> 
>>> --
>>> John S. Erickson, Ph.D.
>>> Director, Web Science Operations
>>> Tetherless World Constellation (RPI)
>>> <http://tw.rpi.edu> <olyerickson@gmail.com>
>>> Twitter & Skype: olyerickson
>> 
>> Social Web Architect
>> http://bblfish.net/
>> 
> 

Social Web Architect
http://bblfish.net/

Received on Sunday, 29 January 2012 13:42:55 UTC