You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@tuscany.apache.org by Amita Vadhavkar <am...@gmail.com> on 2007/07/12 16:26:23 UTC
Re: [DAS] XQuery-DAS
Hi All,
I am just trying to get the discussion open for XQuery DAS.
In the path of building XQuery DAS implementation, it will be
helpful to have code structure which can support different XQuery
Implementations
and not stick to one.
I am trying to use DB2 Express's XQuery support as its a freeware. (XQEngine
has licensing issues, )
XQuery DAS uses Service Provider framework to invoke required service
flavour of
DAS, like XQuery/LDAP.(Thanks to Luciano, his sandbox has some api, impl
separation) Further, we can consider different XQuery implementations like
DB2 Express, Saxon,.... The Service Provider framework similar to above can
be used here too, to customize the DAS instance for a particular XQuery
Impl.
Also, we need to consider the fact that connection to data source can be -
database
connection, file system connection,....and keep the api module generic
enough to accomodate that. I am changing the das-api a bit around that.
Attaching a brief class diagram.
Please give comments, suggestions.
Regards,
Amita
On 6/21/07, ant elder <an...@apache.org> wrote:
>
> Unfortunately it looks like XQEngine is GPL so unusable, we can't even
> have
> code using it in SVN. The only alternative i can think of is Saxon, maybe
> others know of something else?
>
> ...ant
>
> On 6/21/07, Amita Vadhavkar <am...@gmail.com> wrote:
> >
> > Hi,
> > Need some help marked with #.
> >
> > In the implementation of XQuery DAS, I am trying to start simple and
> then
> > gather requirements and features on the way and keep building.
> >
> > #For the first attempt, I am trying with sourceforge's XQEngine as the
> > XQuery engine, as it has no license restrictions. Has anybody any
> comment
> > about which implementation is better/worse?
> >
> > I want to create JIRA for XQuery DAS to attach first patch on the top
> of
> > code available in
> > https://svn.apache.org/repos/asf/incubator/tuscany/sandbox/lresende/das.
> > #Help! Need somebody to create a new Component - Java DAS XQuery.
> >
> >
> https://svn.apache.org/repos/asf/incubator/tuscany/sandbox/lresende/dashas
> > a clear separation of api vs. impelmentation.
> >
> > In the first patch, I am trying to implement
> > org.apache.tuscany.dasinterfaces from tuscany-das-api into
> > tuscany-das-xquery and also using
> > ServiceProvider framework to invoke xquery implementation.
> >
> > The code is very basic and working for single directory/single xml file
> 's
> > xquery expression
> > evaluation and there is nothing done for building a very basic
> DataObject
> > (in-progress)
> > The beginning of the mail thread has many features, here the features to
> > be
> > implemented in the order or importance, please add/comments to it.
> >
> >
> ****************************************************************************************
> > In the first attempt only xml files are considered and not databases
> > supporting XQuery.
> > As the development progresses - will attach a detailed design doc
> instead
> > of
> > having large mails - for easy review.
> >
> > Features List
> > 1) support connection to FileSystem (no authentication considered, only
> > mapped drive and directory)
> > 2) support xquery expessions as Command (using XQEngine to get result)
> > 3) mapping between result of xquery Command to DataObject (XQEngine can
> > emit
> > the xml , form a DataObject using XMLHelper)
> > 4) CRUD support - involves mapping from DataObject to xml document,
> change
> > summary to be added to file
> > 5) FLWOR expression as Command
> > 6) JOIN operation (use multiple files)
> >
> > Test Cases List
> > Ideally will have > 1 test case for each feature
> >
> >
> ****************************************************************************************
> > Hoping to make XQuery DAS useful to the community as an alternative to
> > other
> > DAS flavours.
> >
> > Regards,
> > Amita
> >
> >
> > On 6/15/07, Amita Vadhavkar <am...@gmail.com> wrote:
> > >
> > > Hi All,
> > > After a while on RDB DAS beta1 , I am trying to do more on XQuery DAS.
> > >
> > > Tried to check different XQuery implementations available, below is
> > > summary:
> > >
> > > http://www.axyana.com///products.html Quizx/open - open source
> > > Quizx/db(XQuest) - not open source
> > >
> > > http://www.gnu.org/software/qexo/ - license? - kawa
> > > it compiles XQuery expressions and programs to Java bytecodes , this
> > does
> > > not have
> > > API to be used, so not of much use
> > >
> > > http://www.oracle.com/technology/sample_code/tech/xml/xmldb/jxqi.html-
> > > license will be a problem
> > >
> > > ***http://dsd.lbl.gov/nux/api/index.html -
> > > http://dsd.lbl.gov/nux/license.html
> > > has good set of APIs. I am not sure if the license poses some
> > restrictions
> > > on use.
> > > Looks like this will be a good choice to give first attempt for XQuery
> > > DAS.
> > > Any advise?
> > >
> > > http://saxon.sourceforge.net/ - only SAXON-B is fee and SAXON-SA is
> > > commercial,So may not be a good choice
> > >
> > > I am trying to start based on
> > >
> https://svn.apache.org/repos/asf/incubator/tuscany/sandbox/lresende/das/
> > > This uses Service Provider API to separate different DAS
> > implementations.
> > > There is
> > >
> http://www.mail-archive.com/tuscany-dev@ws.apache.org/msg14428.htmlthread
> > > to discuss the high level approach to provide this. Please add your
> > comments
> > > there for refactoring approach.
> > >
> > > We can use the current mail thread for XQuery DAS specific comments.
> > Also,
> > > I will use
> > > a new page on
> > http://cwiki.apache.org/confluence/display/TUSCANYWIKI/Home
> > >
> > > to track detailed status for XQuery DAS. I will make sure not to link
> > this
> > > page
> > > to any other page, so as not to mess up with ongoing release.
> > >
> > > Regards,
> > > Amita
> > >
> > >
> > > On 4/4/07, Luciano Resende <lu...@gmail.com> wrote:
> > > >
> > > > Hi Amita
> > > >
> > > > Related to the features, I think it's fine to start simple and get
> > > > improvements gradatively as we progress...
> > > >
> > > > Some issues that you have identified:
> > > > - Config model more flexible to accommodate differences between
> > > > multiple implementation
> > > > - Factory issues, and the ability to get different implementations
> > > > Are already available in my sandbox [1] as part of the work I did to
> > > > accommodate multiple DAS implementations [2]
> > > >
> > > > It's probably good idea to keep a XQuery DAS page on the Wiki and
> keep
> > > > updating it with requirements, discussions and design we are
> taking...
> > > >
> > > > [1] -
> > > >
> > https://svn.apache.org/repos/asf/incubator/tuscany/sandbox/lresende/das/
> > > > [2] -
> > > > http://www.mail-archive.com/tuscany-dev@ws.apache.org/msg14428.html
> > > >
> > > > On 3/26/07, Amita Vadhavkar <am...@gmail.com> wrote:
> > > > >
> > > > > Hi All,
> > > > > I am trying to create a prototype for supporting XQuery-DAS. Below
> > are
> > > > > some points I have gathered so far.
> > > > > Please give your comments, add to the points.
> > > > >
> > > > > 1) Basic Features that can be supported:-
> > > > > >>Need to support associating path expression to xml data source.
> > > > >
> > > > > >>Parameter passing in path expression
> > > > >
> > > > > >>Support for FLWOR expressions - use of parameters, data source
> > name
> > > > >
> > > > > >>JOIN operation will involve multiple data sources and multiple
> > > > > expressions
> > > > > - need to support association
> > > > > for same.
> > > > >
> > > > > >>Support for XQuery update facility
> > > > >
> > > > > 2) Places where current das config/code needs to be modified:-
> > > > > >>Provide flexibility in config to support RDB/XQUery/xyz...Can
> have
> > > > > expansion to
> > > > > current config.xsd to support multiple connections of multiple
> > types?
> > > > like
> > > > > RDB/XQuery...
> > > > >
> > > > > >>Command - needs to take care of associating multiple data
> sources
> > > > with
> > > > > multiple expressions
> > > > > say, in RDB - its select from t1, t2...
> > > > > in XQuery - the FLWOR - we can say books.xml <-> expr1, stores.xml
> <->
> > > > > expr2
> > > > > and have a JOIN.
> > > > >
> > > > > >>Getting connection to data store - should be in Interface-Impl ,
> > not
> > > > > directly in impl- like
> > > > > it is currently there in DASImpl not in DAS, to keep it generic.
> > > > >
> > > > > >>graph building related classes should also have separation of
> > > > interface
> > > > > and implementation.
> > > > >
> > > > >
> > > > > 3) What can be kept for in-future and what is MUST for the first
> > cut:-
> > > > > Need comments from you all.
> > > > >
> > > > > 4) Questions:-
> > > > > >>In RDB-DAS we do not support connection to multiple databases.
> > Even
> > > > > JIRA-952 talks
> > > > > only about multiple schemas. Is there any requirement for this/
> > > > constraint
> > > > > due to which
> > > > > we need to stick to single database?
> > > > >
> > > > > >>Also, in future, there can be mix of data stores, RDB, XQuery,
> > ....
> > > > What
> > > > > are the pros/cons
> > > > > for supporting connection to multiple different types of
> datastores
> > > > > (like one RDB compliant, one XQuery compliant)
> > > > >
> > > > > 5) Link from ML - [DAS] Refactoring DAS to allow multiple
> > > > implementatons
> > > > >
> http://www.mail-archive.com/tuscany-dev@ws.apache.org/msg14428.html
> > > > > During the attempt to separate APIs from Impl, we can now decide
> on
> > > > the
> > > > > approach and structure the design.
> > > > >
> > > > > Regards,
> > > > > Amita
> > > > >
> > > >
> > > >
> > > >
> > > > --
> > > > Luciano Resende
> > > > http://people.apache.org/~lresende
> > > >
> > >
> > >
> >
>
Re: [DAS] XQuery-DAS
Posted by Luciano Resende <lu...@gmail.com>.
Comments inline
On 7/18/07, Amita Vadhavkar <am...@gmail.com> wrote:
> Hi ,
> I am trying to summarize some updates on progress in XQuery DAS -
> extended the Service Provider framework to support invocation of
> different XQuery Implementations.
>
> Open Issues:-
> I am considering 2 alternative XQuery Implementations
>
> 1) DB2 Express
> - here my main concern is, is it possible to get any db2 jars under maven
> repo?
> - based on license, will there be any problems in getting this under maven
> repo?
> anybody any clue?
When connecting to DB2, what are the jars going to be used for ? I'd
imagine this scenario would be simmilar to regular RDB DAS connecting
to MySQL, where we give people the proper instructions to configure
their environment (e.g download JDBC driver) so DAS could work with.
>
> 2) Saxon
> Some plus points here are
> - it is following XQJ compliance (not completely)
> - there is a claim that Flat File as well as Database back end is supported.
>
> (I have come across problems when checking the database support in saxon-b,
> getting exception when I try to pass JDBC Connection in SaxonXQDataSource()
> constructor , looks like - not yet implemented - in Saxon)
>
> Some open issues are
> - 2 Saxon jars are required at minimal to use XQJ compliance - saxon8 and
> saxon8-xqj.
> (which are part of version 8.9), but the highest version I could see in
> maven repos
> was 8.7 and so 3 jars (including xqj) are missing too.
> > - So, either, we need to leave XQJ ((:), and use whatever is available in
> 8.7 or otherwise
> have a way to get the latest saxon version in maven repos. It will be great
> if latest 8.9
> saxon can appear in maven repo.
If we decide to use this libraries, we could contact the Saxon
community at sourceforge and check if they would upload the required
to maven. I'm not sure if we could directly try to work with maven
team to post these libraries to some maven repo.
>
> Regards,
> Amita
> On 7/15/07, Amita Vadhavkar <am...@gmail.com> wrote:
> >
> > Hi,
> > Yes, Saxon was suggested by Ant also before and it has saxon-b as
> > freeware.
> > Anybody please any comment on any licensing restrictions? Also I was just
> > giving a try to DB2 Express XQuery support. There are a couple of others
> > listed in June
> > 15 mail, in this same thread. Saxon will be a good choice from XQJ
> > compliance point too.
> > (I will be able to upload a patch in 1-2 days time on the top of what
> > is there in https://svn.apache.org/repos/asf/incubator/tuscany/sandbox/lresende/das/
> >
> > with some documentation to continue design discussion)
> >
> > Regards,
> > Amita
> >
> > On 7/13/07, Doug Tidwell < dtidwell@us.ibm.com> wrote:
> > >
> > > Gang, how is XPath support implemented today? I've looked at the code
> > > briefly in the past, but couldn't make sense of it. I was hoping that
> > > XPath support came from the Xalan jar files. If that were true, it
> > > would
> > > be a SMOP to replace the Xalan XPath libraries with the Saxon libraries.
> > > Saxon supports XSLT 2.0, XPath 2.0 and XQuery.
> > >
> > > That's a straightforward approach to leveraging someone else's excellent
> > > work, although I don't know if Saxon's license would be compatible.
> > >
> > > Anyway, if somebody knows how XPath is implemented now, that would be a
> > > start towards figuring out how to plug in an XQuery engine.
> > >
> > > Cheers,
> > > -Doug
> >
> >
> >
>
--
Luciano Resende
Apache Tuscany Committer
http://people.apache.org/~lresende
http://lresende.blogspot.com/
---------------------------------------------------------------------
To unsubscribe, e-mail: tuscany-dev-unsubscribe@ws.apache.org
For additional commands, e-mail: tuscany-dev-help@ws.apache.org
Re: [DAS] XQuery-DAS
Posted by Amita Vadhavkar <am...@gmail.com>.
Hi ,
I am trying to summarize some updates on progress in XQuery DAS -
extended the Service Provider framework to support invocation of
different XQuery Implementations.
Open Issues:-
I am considering 2 alternative XQuery Implementations
1) DB2 Express
- here my main concern is, is it possible to get any db2 jars under maven
repo?
- based on license, will there be any problems in getting this under maven
repo?
anybody any clue?
2) Saxon
Some plus points here are
- it is following XQJ compliance (not completely)
- there is a claim that Flat File as well as Database back end is supported.
(I have come across problems when checking the database support in saxon-b,
getting exception when I try to pass JDBC Connection in SaxonXQDataSource()
constructor , looks like - not yet implemented - in Saxon)
Some open issues are
- 2 Saxon jars are required at minimal to use XQJ compliance - saxon8 and
saxon8-xqj.
(which are part of version 8.9), but the highest version I could see in
maven repos
was 8.7 and so 3 jars (including xqj) are missing too.
- So, either, we need to leave XQJ ((:), and use whatever is available in
8.7 or otherwise
have a way to get the latest saxon version in maven repos. It will be great
if latest 8.9
saxon can appear in maven repo.
Regards,
Amita
On 7/15/07, Amita Vadhavkar <am...@gmail.com> wrote:
>
> Hi,
> Yes, Saxon was suggested by Ant also before and it has saxon-b as
> freeware.
> Anybody please any comment on any licensing restrictions? Also I was just
> giving a try to DB2 Express XQuery support. There are a couple of others
> listed in June
> 15 mail, in this same thread. Saxon will be a good choice from XQJ
> compliance point too.
> (I will be able to upload a patch in 1-2 days time on the top of what
> is there in https://svn.apache.org/repos/asf/incubator/tuscany/sandbox/lresende/das/
>
> with some documentation to continue design discussion)
>
> Regards,
> Amita
>
> On 7/13/07, Doug Tidwell < dtidwell@us.ibm.com> wrote:
> >
> > Gang, how is XPath support implemented today? I've looked at the code
> > briefly in the past, but couldn't make sense of it. I was hoping that
> > XPath support came from the Xalan jar files. If that were true, it
> > would
> > be a SMOP to replace the Xalan XPath libraries with the Saxon libraries.
> > Saxon supports XSLT 2.0, XPath 2.0 and XQuery.
> >
> > That's a straightforward approach to leveraging someone else's excellent
> > work, although I don't know if Saxon's license would be compatible.
> >
> > Anyway, if somebody knows how XPath is implemented now, that would be a
> > start towards figuring out how to plug in an XQuery engine.
> >
> > Cheers,
> > -Doug
>
>
>
Re: [DAS] XQuery-DAS
Posted by Amita Vadhavkar <am...@gmail.com>.
Hi ,
I am trying to summarize some updates on progress in XQuery DAS -
extended the Service Provider framework to support invocation of
different XQuery Implementations.
Open Issues:-
I am considering 2 alternative XQuery Implementations
1) DB2 Express
- here my main concern is, is it possible to get any db2 jars under maven
repo?
- based on license, will there be any problems in getting this under maven
repo?
anybody any clue?
2) Saxon
Some plus points here are
- it is following XQJ compliance (not completely)
- there is a claim that Flat File as well as Database back end is supported.
(I have come across problems when checking the database support in saxon-b,
getting exception when I try to pass JDBC Connection in SaxonXQDataSource()
constructor , looks like - not yet implemented - in Saxon)
Some open issues are
- 2 Saxon jars are required at minimal to use XQJ compliance - saxon8 and
saxon8-xqj.
(which are part of version 8.9), but the highest version I could see in
maven repos
was 8.7 and so 3 jars (including xqj) are missing too.
- So, either, we need to leave XQJ ((:), and use whatever is available in
8.7 or otherwise
have a way to get the latest saxon version in maven repos. It will be great
if latest 8.9
saxon can appear in maven repo.
Regards,
Amita
On 7/15/07, Amita Vadhavkar <am...@gmail.com> wrote:
>
> Hi,
> Yes, Saxon was suggested by Ant also before and it has saxon-b as
> freeware.
> Anybody please any comment on any licensing restrictions? Also I was just
> giving a try to DB2 Express XQuery support. There are a couple of others
> listed in June
> 15 mail, in this same thread. Saxon will be a good choice from XQJ
> compliance point too.
> (I will be able to upload a patch in 1-2 days time on the top of what
> is there in https://svn.apache.org/repos/asf/incubator/tuscany/sandbox/lresende/das/
>
> with some documentation to continue design discussion)
>
> Regards,
> Amita
>
> On 7/13/07, Doug Tidwell < dtidwell@us.ibm.com> wrote:
> >
> > Gang, how is XPath support implemented today? I've looked at the code
> > briefly in the past, but couldn't make sense of it. I was hoping that
> > XPath support came from the Xalan jar files. If that were true, it
> > would
> > be a SMOP to replace the Xalan XPath libraries with the Saxon libraries.
> > Saxon supports XSLT 2.0, XPath 2.0 and XQuery.
> >
> > That's a straightforward approach to leveraging someone else's excellent
> > work, although I don't know if Saxon's license would be compatible.
> >
> > Anyway, if somebody knows how XPath is implemented now, that would be a
> > start towards figuring out how to plug in an XQuery engine.
> >
> > Cheers,
> > -Doug
>
>
>
Re: [DAS] XQuery-DAS
Posted by Amita Vadhavkar <am...@gmail.com>.
Hi,
Yes, Saxon was suggested by Ant also before and it has saxon-b as freeware.
Anybody please any comment on any licensing restrictions? Also I was just
giving a try to DB2 Express XQuery support. There are a couple of others
listed in June
15 mail, in this same thread. Saxon will be a good choice from XQJ
compliance point too.
(I will be able to upload a patch in 1-2 days time on the top of what
is there in
https://svn.apache.org/repos/asf/incubator/tuscany/sandbox/lresende/das/
with some documentation to continue design discussion)
Regards,
Amita
On 7/13/07, Doug Tidwell <dt...@us.ibm.com> wrote:
>
> Gang, how is XPath support implemented today? I've looked at the code
> briefly in the past, but couldn't make sense of it. I was hoping that
> XPath support came from the Xalan jar files. If that were true, it would
> be a SMOP to replace the Xalan XPath libraries with the Saxon libraries.
> Saxon supports XSLT 2.0, XPath 2.0 and XQuery.
>
> That's a straightforward approach to leveraging someone else's excellent
> work, although I don't know if Saxon's license would be compatible.
>
> Anyway, if somebody knows how XPath is implemented now, that would be a
> start towards figuring out how to plug in an XQuery engine.
>
> Cheers,
> -Doug
Re: [DAS] XQuery-DAS
Posted by Amita Vadhavkar <am...@gmail.com>.
Hi,
Yes, Saxon was suggested by Ant also before and it has saxon-b as freeware.
Anybody please any comment on any licensing restrictions? Also I was just
giving a try to DB2 Express XQuery support. There are a couple of others
listed in June
15 mail, in this same thread. Saxon will be a good choice from XQJ
compliance point too.
(I will be able to upload a patch in 1-2 days time on the top of what
is there in
https://svn.apache.org/repos/asf/incubator/tuscany/sandbox/lresende/das/
with some documentation to continue design discussion)
Regards,
Amita
On 7/13/07, Doug Tidwell <dt...@us.ibm.com> wrote:
>
> Gang, how is XPath support implemented today? I've looked at the code
> briefly in the past, but couldn't make sense of it. I was hoping that
> XPath support came from the Xalan jar files. If that were true, it would
> be a SMOP to replace the Xalan XPath libraries with the Saxon libraries.
> Saxon supports XSLT 2.0, XPath 2.0 and XQuery.
>
> That's a straightforward approach to leveraging someone else's excellent
> work, although I don't know if Saxon's license would be compatible.
>
> Anyway, if somebody knows how XPath is implemented now, that would be a
> start towards figuring out how to plug in an XQuery engine.
>
> Cheers,
> -Doug
Re: [DAS] XQuery-DAS
Posted by Doug Tidwell <dt...@us.ibm.com>.
Gang, how is XPath support implemented today? I've looked at the code
briefly in the past, but couldn't make sense of it. I was hoping that
XPath support came from the Xalan jar files. If that were true, it would
be a SMOP to replace the Xalan XPath libraries with the Saxon libraries.
Saxon supports XSLT 2.0, XPath 2.0 and XQuery.
That's a straightforward approach to leveraging someone else's excellent
work, although I don't know if Saxon's license would be compatible.
Anyway, if somebody knows how XPath is implemented now, that would be a
start towards figuring out how to plug in an XQuery engine.
Cheers,
-Doug
Re: [DAS] XQuery-DAS
Posted by Luciano Resende <lu...@gmail.com>.
Some comments inline...
BTW, if you have started anything, feel free to start submitting
patches and I can apply those to my sandbox. This way others, and
myself, can give better comments.
On 7/12/07, Amita Vadhavkar <am...@gmail.com> wrote:
> Hi All,
> I am just trying to get the discussion open for XQuery DAS.
>
Good, it would be great to get some more community involvement here, I
remember Ron had expressed some requirements on similar area[1], he
might have some requirements, or he might be able to help on the
discussions.
[1] http://www.mail-archive.com/tuscany-user@ws.apache.org/msg00714.html
> In the path of building XQuery DAS implementation, it will be
> helpful to have code structure which can support different XQuery
> Implementations
> and not stick to one.
>
+1
> I am trying to use DB2 Express's XQuery support as its a freeware.
> (XQEngine has licensing issues, )
>
So, what you are saying here is that the XQuery execution is being
done on the DBMS side, and we are not using any third party libraries,
is this correct ? I think this gives us the simplest scenario to work.
> XQuery DAS uses Service Provider framework to invoke required service
> flavour of
> DAS, like XQuery/LDAP.(Thanks to Luciano, his sandbox has some api, impl
> separation) Further, we can consider different XQuery implementations like
> DB2 Express, Saxon,.... The Service Provider framework similar to above can
> be used here too, to customize the DAS instance for a particular XQuery
> Impl.
+1
>
> Also, we need to consider the fact that connection to data source can be -
> database
> connection, file system connection,....and keep the api module generic
> enough to accomodate that. I am changing the das-api a bit around that.
> Attaching a brief class diagram.
>
Got me confused here, if you are using the design in my sandbox, each
DAS implementation would define it's own config model, so you don't
really need to change das api, but I don't know all the details
here... so I'm not sure..
> Please give comments, suggestions.
>
> Regards,
> Amita
>
>
> On 6/21/07, ant elder <an...@apache.org> wrote:
> > Unfortunately it looks like XQEngine is GPL so unusable, we can't even
> have
> > code using it in SVN. The only alternative i can think of is Saxon, maybe
> > others know of something else?
> >
> > ...ant
> >
> > On 6/21/07, Amita Vadhavkar < amita.vadhavkar@gmail.com> wrote:
> > >
> > > Hi,
> > > Need some help marked with #.
> > >
> > > In the implementation of XQuery DAS, I am trying to start simple and
> then
> > > gather requirements and features on the way and keep building.
> > >
> > > #For the first attempt, I am trying with sourceforge's XQEngine as the
> > > XQuery engine, as it has no license restrictions. Has anybody any
> comment
> > > about which implementation is better/worse?
> > >
> > > I want to create JIRA for XQuery DAS to attach first patch on the top
> of
> > > code available in
> > >
> https://svn.apache.org/repos/asf/incubator/tuscany/sandbox/lresende/das.
> > > #Help! Need somebody to create a new Component - Java DAS XQuery.
> > >
> > >
> https://svn.apache.org/repos/asf/incubator/tuscany/sandbox/lresende/dashas
> > > a clear separation of api vs. impelmentation.
> > >
> > > In the first patch, I am trying to implement
> > > org.apache.tuscany.dasinterfaces from tuscany-das-api
> into
> > > tuscany-das-xquery and also using
> > > ServiceProvider framework to invoke xquery implementation.
> > >
> > > The code is very basic and working for single directory/single xml file
> 's
> > > xquery expression
> > > evaluation and there is nothing done for building a very basic
> DataObject
> > > (in-progress)
> > > The beginning of the mail thread has many features, here the features to
> > > be
> > > implemented in the order or importance, please add/comments to it.
> > >
> > >
> ****************************************************************************************
> > > In the first attempt only xml files are considered and not databases
> > > supporting XQuery.
> > > As the development progresses - will attach a detailed design doc
> instead
> > > of
> > > having large mails - for easy review.
> > >
> > > Features List
> > > 1) support connection to FileSystem (no authentication considered, only
> > > mapped drive and directory)
> > > 2) support xquery expessions as Command (using XQEngine to get result)
> > > 3) mapping between result of xquery Command to DataObject (XQEngine can
> > > emit
> > > the xml , form a DataObject using XMLHelper)
> > > 4) CRUD support - involves mapping from DataObject to xml document,
> change
> > > summary to be added to file
> > > 5) FLWOR expression as Command
> > > 6) JOIN operation (use multiple files)
> > >
> > > Test Cases List
> > > Ideally will have > 1 test case for each feature
> > >
> > >
> ****************************************************************************************
> > > Hoping to make XQuery DAS useful to the community as an alternative to
> > > other
> > > DAS flavours.
> > >
> > > Regards,
> > > Amita
> > >
> > >
> > > On 6/15/07, Amita Vadhavkar <am...@gmail.com> wrote:
> > > >
> > > > Hi All,
> > > > After a while on RDB DAS beta1 , I am trying to do more on XQuery DAS.
> > > >
> > > > Tried to check different XQuery implementations available, below is
> > > > summary:
> > > >
> > > > http://www.axyana.com///products.html Quizx/open -
> open source
> > > > Quizx/db(XQuest) - not open source
> > > >
> > > > http://www.gnu.org/software/qexo/ - license? - kawa
> > > > it compiles XQuery expressions and programs to Java bytecodes , this
> > > does
> > > > not have
> > > > API to be used, so not of much use
> > > >
> > > >
> http://www.oracle.com/technology/sample_code/tech/xml/xmldb/jxqi.html
> -
> > > > license will be a problem
> > > >
> > > > ***http://dsd.lbl.gov/nux/api/index.html -
> > > > http://dsd.lbl.gov/nux/license.html
> > > > has good set of APIs. I am not sure if the license poses some
> > > restrictions
> > > > on use.
> > > > Looks like this will be a good choice to give first attempt for XQuery
> > > > DAS.
> > > > Any advise?
> > > >
> > > > http://saxon.sourceforge.net/ - only SAXON-B is fee and SAXON-SA is
> > > > commercial,So may not be a good choice
> > > >
> > > > I am trying to start based on
> > > >
> https://svn.apache.org/repos/asf/incubator/tuscany/sandbox/lresende/das/
> > > > This uses Service Provider API to separate different DAS
> > > implementations.
> > > > There is
> > > >
> http://www.mail-archive.com/tuscany-dev@ws.apache.org/msg14428.htmlthread
> > > > to discuss the high level approach to provide this. Please add your
> > > comments
> > > > there for refactoring approach.
> > > >
> > > > We can use the current mail thread for XQuery DAS specific comments.
> > > Also,
> > > > I will use
> > > > a new page on
> > >
> http://cwiki.apache.org/confluence/display/TUSCANYWIKI/Home
> > > >
> > > > to track detailed status for XQuery DAS. I will make sure not to link
> > > this
> > > > page
> > > > to any other page, so as not to mess up with ongoing release.
> > > >
> > > > Regards,
> > > > Amita
> > > >
> > > >
> > > > On 4/4/07, Luciano Resende <lu...@gmail.com> wrote:
> > > > >
> > > > > Hi Amita
> > > > >
> > > > > Related to the features, I think it's fine to start simple and get
> > > > > improvements gradatively as we progress...
> > > > >
> > > > > Some issues that you have identified:
> > > > > - Config model more flexible to accommodate differences between
> > > > > multiple implementation
> > > > > - Factory issues, and the ability to get different implementations
> > > > > Are already available in my sandbox [1] as part of the work I did to
> > > > > accommodate multiple DAS implementations [2]
> > > > >
> > > > > It's probably good idea to keep a XQuery DAS page on the Wiki and
> keep
> > > > > updating it with requirements, discussions and design we are
> taking...
> > > > >
> > > > > [1] -
> > > > >
> > >
> https://svn.apache.org/repos/asf/incubator/tuscany/sandbox/lresende/das/
> > > > > [2] -
> > > > >
> http://www.mail-archive.com/tuscany-dev@ws.apache.org/msg14428.html
> > > > >
> > > > > On 3/26/07, Amita Vadhavkar < amita.vadhavkar@gmail.com> wrote:
> > > > > >
> > > > > > Hi All,
> > > > > > I am trying to create a prototype for supporting XQuery-DAS. Below
> > > are
> > > > > > some points I have gathered so far.
> > > > > > Please give your comments, add to the points.
> > > > > >
> > > > > > 1) Basic Features that can be supported:-
> > > > > > >>Need to support associating path expression to xml data source.
> > > > > >
> > > > > > >>Parameter passing in path expression
> > > > > >
> > > > > > >>Support for FLWOR expressions - use of parameters, data source
> > > name
> > > > > >
> > > > > > >>JOIN operation will involve multiple data sources and multiple
> > > > > > expressions
> > > > > > - need to support association
> > > > > > for same.
> > > > > >
> > > > > > >>Support for XQuery update facility
> > > > > >
> > > > > > 2) Places where current das config/code needs to be modified:-
> > > > > > >>Provide flexibility in config to support RDB/XQUery/xyz...Can
> have
> > > > > > expansion to
> > > > > > current config.xsd to support multiple connections of multiple
> > > types?
> > > > > like
> > > > > > RDB/XQuery...
> > > > > >
> > > > > > >>Command - needs to take care of associating multiple data
> sources
> > > > > with
> > > > > > multiple expressions
> > > > > > say, in RDB - its select from t1, t2...
> > > > > > in XQuery - the FLWOR - we can say books.xml <-> expr1,
> stores.xml<->
> > > > > > expr2
> > > > > > and have a JOIN.
> > > > > >
> > > > > > >>Getting connection to data store - should be in Interface-Impl ,
> > > not
> > > > > > directly in impl- like
> > > > > > it is currently there in DASImpl not in DAS, to keep it generic.
> > > > > >
> > > > > > >>graph building related classes should also have separation of
> > > > > interface
> > > > > > and implementation.
> > > > > >
> > > > > >
> > > > > > 3) What can be kept for in-future and what is MUST for the first
> > > cut:-
> > > > > > Need comments from you all.
> > > > > >
> > > > > > 4) Questions:-
> > > > > > >>In RDB-DAS we do not support connection to multiple databases.
> > > Even
> > > > > > JIRA-952 talks
> > > > > > only about multiple schemas. Is there any requirement for this/
> > > > > constraint
> > > > > > due to which
> > > > > > we need to stick to single database?
> > > > > >
> > > > > > >>Also, in future, there can be mix of data stores, RDB, XQuery,
> > > ....
> > > > > What
> > > > > > are the pros/cons
> > > > > > for supporting connection to multiple different types of
> datastores
> > > > > > (like one RDB compliant, one XQuery compliant)
> > > > > >
> > > > > > 5) Link from ML - [DAS] Refactoring DAS to allow multiple
> > > > > implementatons
> > > > > >
> http://www.mail-archive.com/tuscany-dev@ws.apache.org/msg14428.html
> > > > > > During the attempt to separate APIs from Impl, we can now decide
> on
> > > > > the
> > > > > > approach and structure the design.
> > > > > >
> > > > > > Regards,
> > > > > > Amita
> > > > > >
> > > > >
> > > > >
> > > > >
> > > > > --
> > > > > Luciano Resende
> > > > > http://people.apache.org/~lresende
> > > > >
> > > >
> > > >
> > >
> >
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail:
> tuscany-dev-unsubscribe@ws.apache.org
> For additional commands, e-mail: tuscany-dev-help@ws.apache.org
>
--
Luciano Resende
Apache Tuscany Committer
http://people.apache.org/~lresende
http://lresende.blogspot.com/
---------------------------------------------------------------------
To unsubscribe, e-mail: tuscany-dev-unsubscribe@ws.apache.org
For additional commands, e-mail: tuscany-dev-help@ws.apache.org