Re: [wsrp][interfaces]: Portal Usage Scenario

[Thomas Schaeck <SCHAECK@de.ibm.com>]

Mike,

maybe let's consider this possible definition to figure out whether I
understood correctly:

"A portlet instance is an instance of a portlet template that may be
referenced from 0 or more locations in 0 or more local or remote pages. A
portlet instance is identified by a unique instance handle/ID and defined
by instance data and its type [i.e. the portlet template from which it was
instantiated]."

This may be equivalent to your definition if you use "portlet instance" as
the reference from a particular location on a particluar page to a "portlet
instance" as defined above and the term "personalization data" synonymously
to the term "instance data" in the definition above. Is this the case ?

This would mean "portlet instances" are entities that could be created by
the portal's customizer and be referenced from a local page, or created as
a result of a WSRP createInstance or copyInstance call and be referenced
from a WSRP consumer. Theoretically, in this case you could even imagine
publishing complete page topologies together with all referenced "portlet
instances" for remote use. (This is just a possibility opened up by this
concept, not something that would affect and add complexity to the WSRP
standard - it is the just simple concept of portlet instances as
first-class entities that enables such more sophisticated distributed
scenarios)

Best regards,

Thomas



Michael Freedman <Michael.Freedman@oracle.com> on 04/10/2002 11:23:42 PM

Please respond to Michael Freedman <Michael.Freedman@oracle.com>

To:    Gil Tayar <Gil.Tayar@webcollage.com>
cc:    wsrp@lists.oasis-open.org
Subject:    Re: [wsrp][interfaces]: Portal Usage Scenario



I believe that is how we have defined things:
    portlet instance: a portlet on a page; or more generically a portlet in
the portal layout structure.  From a portal's perspective, the portlet
instance is the  realization of the portlet in the runtime layout
structure.  A portlet instance is derived from a portlet template.  e.g.
when adding a portlet to a page, the  user chooses a portlet template (from
the toolbox).  The template is used to "type" the instance being created.

   personalization data: a set of customized data settings for a portlet
instance. There is an 1 to N relationship between personalization data and
portlet instances.  1 set of personalizations may be shared between
multiple instances.

What is/was a little confusing was Yossi statement that "the same portlet
instance appears in different places in the portal structure".  That is not
what I had indicated in my reply to him -- rather I said was
"personalization [data] can be shared between multiple portlet instances of
the same type."  I.e. portlet instances ARE your runtime manifestations on
a page.  There is a special case where two of these happen to share the
same personalization data.  This tends to come into existence via some kind
of clone operation.  WSRP/portlets care about this in the situation the
service maintains its personalization data.

I hope this helps.
     -Mike-

Gil Tayar wrote:  I second #1, as I outlined in my previous email. I submit
that what is confusing is the term "portlet instance". I would prefer
"portlet instance data" or "portlet customization data" and leave "portlet
instance" to the runtime manifestation on the page, e.g. only when the user
views it.
-----Original Message-----
From: Tamari, Yossi [mailto:yossi.tamari@sapportals.com]
Sent: Tuesday, April 09, 2002 11:28
To: wsrp@lists.oasis-open.org
Subject: RE: [wsrp][interfaces]: Portal Usage Scenario

Thanks for the answers, but I'm still not satisfied on 1 and 2...1. What
bothers me here is that the fact the same portlet instance appears in
different places in the portal structure is completely handled by the
portal. The producer does not know/care where this instance is in the
portal pages. Hence while the feature is logical in the portal framework, I
don't see its relevance to WSRP.2. I see your point, I'm just worried about
performance. We should give this some more thought. Maybe the metadata
could either give a URL\title or say that it is dynamic.    Yossi.
-----Original Message-----
From: Michael Freedman [mailto:Michael.Freedman@oracle.com]
Sent: Tuesday, April 09, 2002 12:06 AM
To: Tamari, Yossi
Cc: wsrp@lists.oasis-open.org
Subject: Re: [wsrp][interfaces]: Portal Usage Scenario

Good questions.

1. What I meant when I said that personalization data can be shared between
multiple instances is that the personalization can be shared between
multiple portlet instances of the same type.  For example I can have two
instances of a Stock portlet that share the same personalization data.  In
this case both instances display the same result.  When either is
customized, the changes are reflected in both as the personalization data
is shared.  This generalization allows a consumer to expose the same
portlet (result) from different levels in its structure.  Remember, a
portlet instance is defined as a particular reference in the structure
(portlet on a page).  If you want the same content in two locations in the
structure you need the function defined here.  One use of this is in a
portal that supports access from multiple devices.  One can envision the
need to allow portal designers/users to maintain different portal
structures between the device (types).  However, in such a world the end
user still wants access to the same content.  Cloning is an operation that
can be used create a second portlet instance with the characteristics that
its personalization data is shared.  So a cloned instance is one that has
the characteristics described above.

2.   Yes, requesting a portlet instance to render a link reference to
itself does mean you ask the portlet to render an URL that returns its
content as markup.  I agree that this operation can often be defined by
meta-data.  However it may not always be static.  In both this case and the
case we need to render a title bar for the portlet we must allow a way for
the portal (consumer) to acquire the portlet's (producers) title.  This is
because the title is commonly personalizable -- hence dynamic.  Further
discussions will resolve whether this occurs during a render operation (get
"Link") or is merely a getTitle API that returns a string.  Done in the
former the portlet gets an opportunity to define/override the standard
getContent URL -- hence I included it in the list.

3.  Whether changes to a portlet template's settings should affect existing
instances is a good question.  We should discuss this in the next phase.  I
will add it to the questions list in this area.  I will also remove the
statement from the document (so it can be added once answered).  I agree
there are basic configuration settings that should be propagated.  An
example would be a news feed portlet that requires the URL of the source be
entered to wire the portlet to a particular news feed.  If this URL changes
there needs to be a way for the update to alter existing instances.  On the
flip side, one can also envision some template settings being the initial
personalization for an end user.  Its not as clear if these values should
be propogated particularly if there is support for > 1 level of
personalization in the instance.

Hope this helps.
    -Mike-

"Tamari, Yossi" wrote: Hi Mike,I need some clarifications:1.
personalization data - What does it mean that it can be shared between
multiple instances? do you mean instances of the same portlet? if so, why
is that a different instances, i.e. why should the consumer request the
exact same data twice? And how is that different from a cloned instance?2.
"You can request a portlet instance render a link reference to itself" -
Does that mean you ask the portlet for a URL that returns its content as
markup? I think this should be part of the meta-data, as it does not need
to be truly dynamic.3. Why should changes to the portlet template's
settings not affect existing instances? If the name of my company was
change, I want the new name rendered in ALL the instances.    Yossi.
-----Original Message-----
From: Michael Freedman [mailto:Michael.Freedman@oracle.com]
Sent: Saturday, April 06, 2002 9:53 PM
To: WSRP
Subject: [wsrp][interfaces]: Portal Usage Scenario
I have attached a short document describing a portal's possible usage
pattern for portlets using the terms we discussed last week.  Please
comment/annotate with new operations or suggested operations to remove.
Please don't annotate with questions intended to clarify the behavior of
the operation, send these separately. The goal for this Thursday's meeting
is to see if we can agree on a preliminary usage pattern and collection of
operations. Hopefully we can then move into enumerating the questions we
need to answer.  In our discussion on Thursday, I expect we will need to
classify at least the operational aspects of the usage scenario along two
axes:

Axis 1:  Is this a valid Portal operation?

   Yes, we all agree this a valid operation
   No, we all agree this is not a valid operation
   Maybe, there is debate whether this is a valid operation.
   Don't know, we need more information and discussion to understand the
   operation before classifying it.


Axis 2: Should this operation be covered/enabled by our spec?

   Yes, we all agree.
   Yes, but it should be addressed in a later revision.
   No, we all agree.
   Maybe, there is debate whether we should address this.
   Don't know, we need more information to decide.

It might be useful if each of you did your own classification (assuming of
course the usage scenario isn't grossly controversial).

    -Mike-