[OpenID] Extensions - required and optional attributes

[Jack]

Johnny Bufu wrote:
> 
> On 13-Sep-07, at 10:21 AM, Jack wrote:
> 
>> If this is not required, then it would remain open to any extension
>>  developer to name these parameters as they see fit; with the 
>> result that the core of the OpenID code, at both the RP and the OP,
>>  has to incorporate specific code to support each supported 
>> extension.
> 
> That's not true: with the use of factories and virtual methods, 
> extension implementations can be added without any modification to 
> the OpenID core implementation.

Alright, I believe you.
> 
> For an example, you can have a look at the 
> org.openid4java.message.Message* and org.openid4java.message.ax.* at 
> http://code.google.com/p/openid4java/

Yes, I have had a look at that; but I think it isn't making complete
sense for me yet, because I don't properly grasp what it is trying to do.
> 
> (The sreg sub-package does have a manual tweak in the core, for 
> reasons specific to SREG and discussed in a previous thread.)

I spent this morning trawling back through the archive of this list;
I've got as far as April, but haven't seen that thread yet (I wish all
archives of technical lists had a search interface!) I'm giving up for
now, in favour of trying to understand what I'm trying to do.
> 
> On the general matter, I don't think the OpenID core should dictate 
> anything about the contents of an extension; it should be just the 
> "transport" layer for extensions, and not interfere with their 
> payloads.

I notice that AX defines the same parameters, but that "optional" is
there named "if_available". But I can see that required/optional isn't
relevant to AQ. So, fair enough.


-- 
Jack Cleaver.