Hi Surajit,

surajit ray wrote:
> Hi Nina,
>
> Are we officially supposed to use the restlet2 m7 ? 
>
The library and particular release are choice of the developer, so the
answer is - it is up to you.  

> At this point I have few questions about this interaction 
> a) Once a time consuming calculation is over - should the server
> notify an attached client about the result OR just sit with the data
> at a specified URL till it is fetched by the client ?
The client sends GET requests and verifies if the result is ready (200
OK). Have a look at the API  at 
http://opentox.org/dev/apis/api-1.1/AsyncTask

When returning 303 (redirect) for an uncomplete task and making use of
Refresh field, it is very easy to implement browser -like client to
periodically check the task status. Browsers will automatically try to
fetch the content after time interval, specified in Refresh:
> (In the REST interface is it allowable for the server to contact a
> connected client ?)
No.  REST is using HTTP protocol for communication and there is no any
notion of an "attached" client.  The client sends GET/PUT/POST/DELETE
request, receives an answer and there is no permanent between them after
the response is sent.
Unless you implement your client to behave as server as well, there is
no way of server to tell the client anything, besides answering client
request.
> b) Should the server identify the client requesting the computation
> and authenticate before delivering the data OR give it to any client
> requesting the URI of the predicted/computed values ?
We've decided to postpone everything, concerning authentication and
authorization after the end of February, and currently all the services
are open to everybody (I know it sounds scary :)
> c) How long should the computed values be retained on the server OR
> should there be REST interface for destroying (and hence freeing up
> resources) a set of computed values ?
It depends on your implementation.

For example ambit services store everything in a database and keep the
results forever, unless a delete operation is performed on specific
resource.  REST way of deleting a resource is sending DELETE request
(instead of POST or PUT, which are generaly for create/update).  For
most of OpenTox resources DELETE operation is defined in the API (see
wiki), but not everybody has implemented the full set of the API.
> d) Should there be an "account" like system for every client on the
> server
See answer in (b).
> ? If yes - should the data generated by a client be attached to that
> "account" or available to all ?
There might be public and private data, but at this moment we consider
everything is public and will decide on details after finalizing
deliverables at the end of this month.
> Should the computed data persist indefinitely in each of these
> "accounts" ?
>
Again, it depends on your implementation.

Best regards,
Nina
> Cheers
> Surajit
>
> On Tue, Feb 2, 2010 at 3:31 AM, Nina Jeliazkova <nina at acad.bg
> <mailto:nina at acad.bg>> wrote:
>
>     Hi Pantelis,
>
>     There is a standard Java class
>     java.util.concurrent.ExecutorService ; it
>     could be configured to work as a pool of fixed or variable number of
>     threads.
>
>     There is a Restlet TaskService , which is wraps the ExecutorService.
>     I've found it behaved weird and switched to the standard Java class.
>
>     You might look at ambit code at
>
>     https://ambit.svn.sourceforge.net/svnroot/ambit/trunk/ambit2-all/ambit2-www/src/main/java/ambit2/rest/AmbitApplication.java
>     https://ambit.svn.sourceforge.net/svnroot/ambit/trunk/ambit2-all/ambit2-www/src/main/java/ambit2/rest/task
>
>     For each asynchronous task, it creates a Callable class, which returns
>     Reference. Each tasks has an unique identifier (UUID) and the set of
>     tasks is stored in a ConcurrentMap. There is a timer, which removes
>     completed tasks few hours after completion.
>
>     Hope this helps,
>     Nina
>
>
>     chung wrote:
>     > Hi Nina,
>     >  I'm trying to make some improvements on the services so except
>     for the
>     > migration from restlet2 m3 to m7 I was thinking of introducing some
>     > execution pool (e.g. an ExecutorService or -why not- something
>     > 'homemade') and establish a queue for the incoming requests
>     (especially
>     > those characterized as time-consuming and memory-consuming
>     ones). This
>     > way I will be able to manage all running tasks on the server and
>     make
>     > some performance improvements I hope. Is there some standard way of
>     > doing this? Could you suggest some executor or some utility to
>     manage
>     > the running threads and do you know if there is some way to
>     specify the
>     > maximum number of running threads for Restlet?
>     >
>     > Best Regards,
>     > Pantelis
>     >
>     >
>     > On Tue, 2010-01-26 at 14:21 +0200, Nina Jeliazkova wrote:
>     >
>     >> Hello All,
>     >>
>     >> Following the data type discussions and proposal earlier this
>     month, now
>     >> support for NumericFeature and NominalFeature are implemented
>     in IDEA
>     >> services.
>     >>
>     >> Please note all features are explicitly declared to be subclass of
>     >> ot:Feature as well. While this is redundant and can be derived
>     from the
>     >> ontology with a help of a reasoner, it does make the client
>     >> implementation somewhat easier.
>     >>
>     >> Examples from CPDBAS dataset at
>     >> http://ambit.uni-plovdiv.bg:8080/ambit2/dataset/9
>     >>
>     >> <http://ambit.uni-plovdiv.bg:8080/ambit2/feature/12122>
>     >>       a       ot:Feature , ot:NominalFeature ;
>     >>       dc:identifier
>     >>
>     "http://ambit.uni-plovdiv.bg:8080/ambit2/feature/12122"^^xsd:anyURI ;
>     >>       dc:title "ActivityOutcome_CPDBAS_SingleCellCall" ;
>     >>       ot:acceptValue "inactive" , "active" ;
>     >>       ot:hasSource
>     >> <http://ambit.uni-plovdiv.bg:8080/ambit2/reference/11847> ;
>     >>       ot:units "" ;
>     >>       =       ot:ActivityOutcome_CPDBAS_SingleCellCall .
>     >>
>     >>
>     >> <http://ambit.uni-plovdiv.bg:8080/ambit2/feature/12124>
>     >>       a       ot:Feature , ot:NumericFeature ;
>     >>       dc:identifier
>     >>
>     "http://ambit.uni-plovdiv.bg:8080/ambit2/feature/12124"^^xsd:anyURI ;
>     >>       dc:title "STRUCTURE_MolecularWeight" ;
>     >>       ot:hasSource
>     >> <http://ambit.uni-plovdiv.bg:8080/ambit2/reference/11847> ;
>     >>       ot:units "" ;
>     >>       =       ot:STRUCTURE_MolecularWeight .
>     >>
>     >>
>     >> Bug reports are of course welcome at the usual place
>     >>
>     >> http://sourceforge.net/tracker/?group_id=191756
>     >>
>     >> Best regards,
>     >> Nina
>     >>
>     >>>
>     >>>
>     >>>>
>     >>>>
>     >>> 1) Feature data types:
>     >>> Proposal (based on Pantelis suggestions and Protege guide) at
>     >>>
>     http://opentox.org/data/documents/development/RDF%20files/Datatypes.
>     >>> Updated opentox.owl at
>     >>>
>     http://opentox.org/data/documents/development/RDF%20files/OpenToxOntology/view
>     >>>
>     >>>
>     >>>
>     >> _______________________________________________
>     >> Development mailing list
>     >> Development at opentox.org <mailto:Development at opentox.org>
>     >> http://www.opentox.org/mailman/listinfo/development
>     >>
>     >>
>     >
>     >
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>     >
>
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>
>
>
> -- 
> Surajit Ray
> Partner
> www.rareindianart.com <http://www.rareindianart.com>