RE: [wsrp] [wsia] [wsrp-wsia joint interfaces] Search results pag e,map services, transient entities.

[Rex Brooks <rexb@starbourne.com>]

This is a new twist on the concept of transient entities, at least as
far as I understood what we meant by the term. I see the utility of
this, but I'm not clear about why it is necessary. This is a way to
do this, but I guess I just don't see what the added value is for
doing it this way as opposed to other ways. In an aggregated service
for one-stop shopping so to speak, I guess maybe it would be somewhat
more convenient, but I would certainly want to test it or get some
information to that effect before I bought it, the service not the
specific hotel reservations. If I saw some figures that proved it was
quicker, or provided some other equally attractive value, I would buy
it.

This may be a case where transient entity is just a specific set of
information, two calls to a database, two images with hyperlinks
associated with them and a bit of processing during a discrete
session. That could be more efficient if the OO aspects mentioned can
be leveraged without transient entities proliferating beyond
expectations. I had thought of transient entities more as volatile
elements like stock quotes with changeable values rather than as
search selections gathered together temporarily.

It definitely gives me more to think about.

Ciao,
Rex

At 11:17 AM -0700 6/12/02, Alan Kropp wrote:
>I'm coming around to this idea.  I guess that coming from the web app
>background, it's difficult to conceive of OO concepts overlaying neatly on
>top of the stateless, loosely-coupled world of HTTP.  I tend to think of
>Ravi's approach as somehow more "natural" for this sort of application, but
>completely see Rich's point.
>
>So to make sure I've got this..The Consumer tells the Producer to construct
>n transient entities, one for each hotel in the search results.  Each
>transient entity represents a distinct state (hotel=Downtown Hilton,
>city=Toronto).  The Consumer can then call performAction() (I don't think
>it's getFragment?) on each transient entity, to get back an appropriate GIF
>that it uses to render the results page.
>
>When the user clicks the GIF, the Consumer transmits a getFragment() request
>to the transient entity, which responds with the full-size map GIF, and
>perhaps text driving directions.
>
>On the Producer side of this, I can see a streamlined implementation where
>there's an instance (in the OO sense) to represent the MapQuest entity, and
>each transient entity is really an in-memory representation of the
>appropriate transient state.  The transient entity handle in the request
>(either performAction or getFragment) tells the Producer which transient
>state to "connect" the MapQuest entity to for this request.
>
>
>Alan
>
>
>
>
>
>
>
>
>
>-----Original Message-----
>From: Rich Thompson [mailto:richt2@us.ibm.com]
>Sent: Wednesday, June 12, 2002 10:23 AM
>To: wsia@lists.oasis-open.org; wsrp@lists.oasis-open.org
>Subject: RE: [wsrp] [wsia] [wsrp-wsia joint interfaces] Search results
>page, map services, transient entities.
>
>
>
>
>It sounds like you are questioning whether the design proposed for the
>Consumer's search result page makes sense. I would respond that not only
>does it make sense, I have seen the equivalent on the web already (don't
>remember where, but it was the basic scenario Eilon laid out). You are
>basically there when you state that the search page could present a set of
>clickable GIFs ... the question is where do these come from. Two basic
>choices are that the Consumer prefetches them into a local cache and just
>makes a connection to the search result record OR that for each result
>record, the Consumer creates a transient entity at a Producer, sets the
>configuration such that an appropriate GIF is generated and the Producer
>includes whatever logic is needed to deal with clicks on the GIF. I would
>argue that the architecture should not exclude either approach (both have
>their advantages) and that the second approach is a good case where the
>context known only by the Consumer is what dictates whether a persistent or
>transient entity is appropriate.
>
>
>
>
>
>                       Ravi
>
>                       Konuru/Watson/IBM        To:
>wsia@lists.oasis-open.org, wsrp@lists.oasis-open.org
>                       @IBMUS                   cc:
>
>                                                Subject:  RE: [wsrp] [wsia]
>[wsrp-wsia joint interfaces] Search
>                       06/12/2002 10:53          results page, map services,
>transient entities.
>                       AM
>
>
>
>
>
>
>
>
>I don't understand why transient entities are created in this scenario. Why
>is the search results page creating the transient entities?
>I can think of a case where the search results page provides a set of
>clickable GIFs that correspond to the hotel services but NOT actually
>create transient entities at the Producer. If the user actually clicks on
>one of them, it is at that time the consumer requests the producer to
>create an entity (transient or persistent) and then embeds the output of
>the entity in its web page.
>
>Am I missing something?
>
>thanks,
>Ravi Konuru
>
>(Embedded image moved to file: pic28419.gif)Carsten Leue/Germany/IBM@IBMDE
>
>
>  (Embed (Embedded image moved to file:     (Embedded image moved to file:
>  ded    pic00419.gif)                      pic30879.gif)
>  image                          Carsten
>  moved                          Leue/Germa To: Eilon Reshef
>  to                             ny/IBM@IBM <eilon.reshef@webcollage.com>
>  file:                          DE         cc: "'Alan Kropp'"
>  pic116                                    <akropp@epicentric.com>,
>  57.gif                                    wsia@lists.oasis-open.org,
>  )                              06/12/2002 wsrp@lists.oasis-open.org
>                                 06:57 AM   Subject: RE: [wsrp] [wsia]
>                                            [wsrp-wsia joint interfaces]
>                                            agenda for Tuesday 11 June
>
>
>
>
>
>
>I think that this is a very good scenario where transient entities make
>sense.
>
>
>Best regards
>Carsten Leue
>
>-------
>Dr. Carsten Leue
>Dept.8288, IBM Laboratory Böblingen , Germany
>Tel.: +49-7031-16-4603, Fax: +49-7031-16-4401
>
>
>
>|---------+----------------------------->
>| | Eilon Reshef |
>| | <eilon.reshef@webc|
>| | ollage.com> |
>| | |
>| | 06/11/2002 08:35 |
>| | PM |
>| | Please respond to |
>| | Eilon Reshef |
>| | |
>|---------+----------------------------->
>>
>----------------------------------------------------------------------------
>-----------------------------------------------------------------|
>
>| |
>| To: "'Alan Kropp'" <akropp@epicentric.com>, wsia@lists.oasis-open.org,
>wsrp@lists.oasis-open.org |
>| cc: |
>| Subject: RE: [wsrp] [wsia] [wsrp-wsia joint interfaces] agenda for
>Tuesday 11 June |
>| |
>| |
>>
>----------------------------------------------------------------------------
>-----------------------------------------------------------------|
>
>
>
>
>Alan,
>
>I think that one example scenario is a search results page, say for hotels,
>that dynamically displays multiple maps - a map for each hotel found.
>
>Assuming that maps are remote services, and assuming that the number of
>results is dynamic, the Consumer needs to create multiple copies of the map
>service. If we allow the Producer to determine the persistence state of
>those maps, that would mean that someone will have to take care of the
>lifetime of those maps. The Consumer can't, because the page may be gone
>without the Consumer never knowing about it (the user closes the browser
>window). The Producer can't, because it can't tell whether the Consumer has
>stored a reference to those maps as part of a design-time description of a
>user page.
>
>Is that along the lines of what you were looking for?
>
>Eilon
>-----Original Message-----
>From: Alan Kropp [mailto:akropp@epicentric.com]
>Sent: Tuesday, June 11, 2002 2:18 PM
>To: 'wsia@lists.oasis-open.org'; 'wsrp@lists.oasis-open.org'
>Subject: RE: [wsrp] [wsia] [wsrp-wsia joint interfaces] agenda for
>Tuesday 11 June
>
>
>
>I find that the question of a Consumer creating a persistent vs. a
>transient
>entity to be a little troubling.
>
>
>Isn't the Consumer primarily interested in getting a handle to an
>_entity_
>(be that transient or persistent), and then using that handle to
>direct
>subsequent requests to?
>
>
>Could we not consider persistence and transience to be entirely
>Producer
>concerns? I understand from the sequence in the spec (pp. 6-8) that
>the
>only supporting scenario for the Consumer calling
>"createTransientEntity" is
>out of an effort to maximize the efficiency of the conversation with
>the
>Producer. This is a worthy goal, of course, but the Producer should
>advertise its interaction behavior in the meta-data, right?
>Presumably the
>Producer uses the meta-data to hint to the Consumer the way(s) the
>Consumer
>SHOULD structure invocation requests efficiently.
>
>
>I'd love to see some more convincing scenarios to support pushing the
>
>persistent/transient aspect of the conversation out to the Consumer.
>Otherwise, I'd love even more to limit our specification to a single
>"createEntity" call.
>
>
>Alan
>
>
>
>
>
>-----Original Message-----
>From: Carsten Leue [mailto:CLEUE@de.ibm.com]
>Sent: Tuesday, June 11, 2002 2:19 AM
>To: Gil Tayar
>Cc: thomas klein6; 'wsia@lists.oasis-open.org';
>'wsrp@lists.oasis-open.org'
>Subject: RE: [wsrp] [wsia] [wsrp-wsia joint interfaces] agenda for
>Tuesday 11 June
>
>
>
>
>
>
>Gil -
>
>
>1-3: the consumer MUST explicitly create entities (transient or
>persistent). It can decide to create sessions explicitly if it wants
>to
>share them amongs entities, otherwise it can let the producer create
>sessions on the fly.
>4: the decision to have multiple entities per session is up to the
>consumer
>who make this choice based on the producer's metadata. e.g think of
>portlets that form a shop together. These would want to share a
>session
>with each other. But the consumer could decide to have two shops of
>the
>same type on the same page. Then there would be two sessions and only
>the
>consumer could know what portlet shares what session.
>5: The consumer should create a session before issuing a getFragment
>call.
>The entity is created whenever necessary.
>6: A Session is a bucket that holds some data (physically on the
>provider)
>and times-out after a while. A transient entity is a remote portlet
>that
>does not store any data in a DB.
>
>
>Hope that helped.
>
>
>Best regards
>Carsten Leue
>
>
>-------
>Dr. Carsten Leue
>Dept.8288, IBM Laboratory Böblingen , Germany
>Tel.: +49-7031-16-4603, Fax: +49-7031-16-4401
>
>
>
>
>
>
>|---------+---------------------------->
>| | Gil Tayar |
>| | <Gil.Tayar@webcol|
>| | lage.com> |
>| | |
>| | 06/11/2002 09:28 |
>| | AM |
>| | Please respond to|
>| | Gil Tayar |
>| | |
>|---------+---------------------------->
>
>>
>---------------------------------------------------------------------------
>
>------------------------------------------------------------------|
>|
>|
>| To: Carsten Leue/Germany/IBM@IBMDE
>|
>| cc: "'wsia@lists.oasis-open.org'"
><wsia@lists.oasis-open.org>, "'wsrp@lists.oasis-open.org'"
><wsrp@lists.oasis-open.org>, Thomas|
>| Klein6/Germany/IBM@IBMDE
>|
>| Subject: RE: [wsrp] [wsia] [wsrp-wsia joint interfaces]
>agenda
>for Tuesday 11 June
>|
>|
>|
>|
>|
>
>>
>---------------------------------------------------------------------------
>
>------------------------------------------------------------------|
>
>
>
>
>
>
>Carsten, could you clarify some things for me?
>
>
>1. If sessions and entities are orthogonal, what SHOULD the Consumer
>do?
>2. SHOULD it create a transient entity _and_ a session?
>3. MUST it do so?
>4. Who gets to decide whether there are multiple entities per session
>or
>multiple sessions per entities?
>5. When SHOULD a Consumer create a session and when a transient
>entity?
>6. What _is_ a session, logically? What _is_ a transient entity?
>
>
>Gil
>
>
>-----Original Message-----
>From: Carsten Leue [mailto:CLEUE@de.ibm.com]
>Sent: Tuesday, June 11, 2002 08:45
>To: Alan Kropp
>Cc: 'wsia@lists.oasis-open.org'; 'wsrp@lists.oasis-open.org'; thomas
>klein6
>Subject: Re: [wsrp] [wsia] [wsrp-wsia joint interfaces] agenda for
>Tuesday 11 June
>
>
>
>
>
>
>Alan - some first thoughts
>
>
>1. the general concept is that entities (transient or persistent) and
>
>sessions are orthogonal. There might be mulitple entities per session
>and
>(at least for persistent entities) multiple sessions per entity. An
>example
>for the first case would be that entities share session data within
>the
>same user request. An example for the second case are portlets on a
>common
>page (group page) that are access simultaneously by multiple users.
>A transient entity differs from a persistent entity in that its data
>does
>not persist and its lifecycle is coupled with the session life cycle.
>
>
>2. Eilon pointed out in a comment to the interface proposal that
>batch
>processing is already part of SOAP. I was not aware of that and will
>look
>it up until the call.
>
>
>
>
>
>Best regards
>Carsten Leue
>
>
>-------
>Dr. Carsten Leue
>Dept.8288, IBM Laboratory Böblingen , Germany
>Tel.: +49-7031-16-4603, Fax: +49-7031-16-4401
>
>
>
>
>
>
>|---------+---------------------------->
>| | Alan Kropp |
>| | <akropp@epicentri|
>| | c.com> |
>| | |
>| | 06/11/2002 01:54 |
>| | AM |
>| | Please respond to|
>| | Alan Kropp |
>| | |
>|---------+---------------------------->
>
>
>>
>---------------------------------------------------------------------------
>
>------------------------------------------------------------------|
>|
>|
>| To: "'wsrp@lists.oasis-open.org'"
><wsrp@lists.oasis-open.org>, "'wsia@lists.oasis-open.org'"
><wsia@lists.oasis-open.org> |
>| cc:
>|
>| Subject: [wsrp] [wsia] [wsrp-wsia joint interfaces] agenda
>for
>Tuesday 11 June
>|
>|
>|
>|
>|
>
>
>>
>---------------------------------------------------------------------------
>
>------------------------------------------------------------------|
>
>
>
>
>
>
>I think we'll have plenty of discussion around the merged document
>Rich and
>Carsten put together.
>
>
>The two main issues I see that have arisen on the email lists are:
>
>
>1. What is the difference between transient entities and sessions,
>and is
>there enough of a distinction to warrant including both in the
>specification?
>
>
>2. There are efficiency concerns around the use of arrays in the
>method
>signatures, basically to enable batched requests for network
>efficiency.
>
>
>
>
>
>Call-in numbers:
>USA Toll Free Number: 877-718-0936
>USA Toll Number: +1-712-923-6878
>PARTICIPANT PASSCODE: 563151
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>
>
>
>
>Alan
>
>
>
>
>
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