RE: URI Templates - optional variables?

Mark Nottingham wrote:
> Out of band. See < 
>> for an example that 
> might help (indirectly).

That seems inband by my earlier definition. And the post didn't seem to be
complete; you mention " enough special cases out there that it would  
quickly make using (and implementing) templates unwieldy" yet the only
conventions you discussed was optional template parameters. I'm confused.
And your post seems to be no different (other than the syntax) from what Roy
Fielding proposed recently.

BTW, this post of mine [1] is very similar to your quoted URL, albeit it
came after yours and I'm pretty sure yours influenced mine.

I also don't think I'm at odds with you, I think I'm just not understanding
your explanation.  

> That's the other approach that's being discussed. The problem 
> here is that there's a potentially large set of such 
> transformation functions that you need to identify; I don't 
> have much confidence that we'll be able to identify all of 
> the useful functions in one go. For example, Roy gives a good 
> start, but we'll also need ways to indicate how to handle 
> encoding. And, what if you want to use (for example) a 
> hash-to- query-string mapping as well as a particular style 
> of encoding?
> As such, I'm suspecting that there'll need to be an answer 
> for extensibility here. That means that we can't enumerate 
> all of the beginning characters that one has to look out for 
> in template variable names; some more general convention is necessary.

Sorry if I wasn't clear.  I think I was saying that the equals denotes
"special processing" not "specific processing," especially after I realized
that it would be good to separate concerns.

> If you buy into that, why not put all of this type of 
> metadata (types, optionality, formatting, encoding, etc.) 
> into the variable definition, and leave it out of the 
> variable names altogether?
> That's my (somewhat weak) preference.

Assuming I fully understand why I'm buying into :), then yes. But I reserve
the right to say I didn't understand. '-)

For clarity, I think it's important that the URI Template can be
self-contained and not need external information to interpret other than the
list of valid values as in a database lookup. Without that it would appear
to me to be as bad an idea as an EPR is compared to a URI.

-Mike Schinkel -


Received on Saturday, 11 August 2007 05:10:10 UTC