[DAS2] DAS vs. Java Web Services

[Thomas Down]

On 9 Jan 2006, at 22:14, Nomi Harris wrote:

> i was talking to someone in the apollo community about writing a DAS/2
> adapter for apollo, and he said:
>
>> I think the Java Web Services model has been proven more so than  
>> the DAS
>> model for standardized web application communication.
>
> this is an interesting claim, and i was wondering if you have any  
> comment
> on why this is wrong (i assume you all disagree with it, or else you
> wouldn't be working on DAS/2).  i think we should address this  
> issue in
> the grant--maybe we can add it to the progress report?  otherwise, the
> review committee could come back and say, "why don't you just use Java
> Web Services instead of developing this new standard?"

It would be interesting to know a little more about what's mean by  
"Java Web Services".  I'm guessing that you contact is talking about  
"web services based on SOAP, WSDL and associated technologies".   
There's nothing Java-centric here, although I guess it's true that a  
lot of the advocates for these technologies are coming from a Java  
or .NET background.

DAS (and DAS/2 in particular) aims for a RESTful style of interaction:

               http://www.ics.uci.edu/~fielding/pubs/dissertation/ 
top.htm

I think the main argument for this was that REST services, which put  
all the query information in a URL, are easier for "casual"  
programmers (who aren't familiar with SOAP client libraries and the  
like) to script about -- and it's even possible to fire a query off  
by typing a URL in your web browser.

The downsides of REST are that you get less benefit from existing  
client libraries and server frameworks, and that (at least in my  
opinion) it's harder to clearly express a rich query language as URLs  
than as POSTed XML fragments.

             Thomas.