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From "Mattmann, Chris A (388J)" <chris.a.mattm...@jpl.nasa.gov>
Subject Re: Query-Servlet-XML-RPC
Date Fri, 13 Jan 2012 16:52:49 GMT
Hi BW,

On Jan 12, 2012, at 10:37 PM, BW wrote:

> Ok Thx. I looked at that.  I'm trying to get a 30k view of the whole picture.

Ok, cool.

> Isn't the query server component part of the substrate where the query handler gets attached?

The QueryServer used to be a component that was seeded with a set of initial Profile Server

endpoints, and then used those Profile Server end points to crawl a directed graph of resources,
either automatically or interactively. As it consumed the resources, it looked for:

* Other Profile Servers -- to add more nodes to crawl (pointed at other resources)
* Product Servers -- to download and package products from
* raw URLs -- to download and package products from

> Suppose, I want to deploy on 3 nodes; Query Handler to 1st for Query Server, Profile
Handler to 2nd for Profile Server and Query Handler to 3rd for Product Server?

If you want to deploy on 3 nodes, the typical model now:

* web grid on each node, running on a Java app server (e.g., Tomcat)
* deploy Profile Handler on 2nd node web grid
* deploy Product Handler on 3rd node web grid
* (optionally) deploy handlers on 1st node
* contact 2nd and 3rd node prof/prod server directly via 
Prof/Prod client or via cURL/wget, etc.

Cheers,
Chris

> 
> On Jan 12, 2012, at 8:55 PM, "Mattmann, Chris A (388J)" <chris.a.mattmann@jpl.nasa.gov>
wrote:
> 
>> Hi BW:
>> 
>> In the current model, it's not done at all. The QueryServlet doesn't really exist
>> since the advent of Web-Grid for the information integration components:
>> 
>> http://oodt.apache.org/components/maven/grid/
>> 
>> Check out the slides from Sean Kelly on that site, that describes web grid.
>> Basically instead of the query server/servlet, we opted for a more REST
>> service oriented style where users consume profile and product server
>> end points via the Web Grid substrate.
>> 
>> Does that help?
>> 
>> Cheers,
>> Chris
>> 
>> On Jan 12, 2012, at 8:50 PM, B W wrote:
>> 
>>> Correct me if I'm wrong, an initial query is posted via a user agent
>>> browser to a servlet for the Query Service then:
>>> The messaging layer broadcasts the query to registered Profile Services
>>> that are running?
>>> Is this done via XML-RPC or posting to the servlets on the Profile Servers?
>>> 
>>> 
>>> I'm trying to figure out the whole thread.
>>> 
>>> Thx.
>>> 
>>> On Thu, Jan 12, 2012 at 8:22 PM, Mattmann, Chris A (388J) <
>>> chris.a.mattmann@jpl.nasa.gov> wrote:
>>> 
>>>> Hey Sean,
>>>> 
>>>>> 
>>>>> The ebXML model is one of the least egregious for a registry that I've
>>>> seen, and believe me, I've seen some nasty ones. But what makes JPL's
>>>> implementation so compelling is its JSON-esque and ReST-ful based API,
>>>> which, as far as I can tell, is totally original within the ebXML & OASIS
>>>> worlds.
>>>>> 
>>>>> Normally I turn my nose up to heavy-handed models with entrenched APIs,
>>>> but the singular achievement of JPL is to make the ebXML model, which
>>>> conceptually isn't byzantine, actually usable, approachable, and extendable.
>>>> 
>>>> Super +1.
>>>> 
>>>>> 
>>>>> Is there any hope we can get JPL, Caltech, and NASA to give it up to
>>>> become part of OODT? Or its own Incubator project?
>>>> 
>>>> I think Hardman is working on it, he can feel free to comment (or not)
>>>> here ^_^
>>>> 
>>>> Cheers,
>>>> Chris
>>>> 
>>>> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>>>> Chris Mattmann, Ph.D.
>>>> Senior Computer Scientist
>>>> NASA Jet Propulsion Laboratory Pasadena, CA 91109 USA
>>>> Office: 171-266B, Mailstop: 171-246
>>>> Email: chris.a.mattmann@nasa.gov
>>>> WWW:   http://sunset.usc.edu/~mattmann/
>>>> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>>>> Adjunct Assistant Professor, Computer Science Department
>>>> University of Southern California, Los Angeles, CA 90089 USA
>>>> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>>>> 
>>>> 
>> 
>> 
>> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>> Chris Mattmann, Ph.D.
>> Senior Computer Scientist
>> NASA Jet Propulsion Laboratory Pasadena, CA 91109 USA
>> Office: 171-266B, Mailstop: 171-246
>> Email: chris.a.mattmann@nasa.gov
>> WWW:   http://sunset.usc.edu/~mattmann/
>> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>> Adjunct Assistant Professor, Computer Science Department
>> University of Southern California, Los Angeles, CA 90089 USA
>> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>> 


++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Chris Mattmann, Ph.D.
Senior Computer Scientist
NASA Jet Propulsion Laboratory Pasadena, CA 91109 USA
Office: 171-266B, Mailstop: 171-246
Email: chris.a.mattmann@nasa.gov
WWW:   http://sunset.usc.edu/~mattmann/
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Adjunct Assistant Professor, Computer Science Department
University of Southern California, Los Angeles, CA 90089 USA
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++


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