Embedded BaseX
Tuesday, 11 July 2017 · 5 messages · last reply 14 Jul 2017
GS
George Sofianos11 Jul 2017 11:36 #
Hello,
I'm building a web service that along with some other things (XML Validation, Saxon XQuery, etc) includes a BaseX processor for running XQuery scripts. I'm wondering what is the best way to use an embedded BaseX processor. Can some objects be shared (e.g Context,
QueryProcessor), or are they very lightweight and there is no need to share / reuse ?
Can I get the number of the jobs running and the job status like in the client / server mode? My intention is to make sure I can limit the amount of the jobs running in parallel, and have more control over the execution (maybe cancel jobs if necessary)
Thanks,
George
CG
Christian Grün11 Jul 2017 14:02 #
Hi George,
It’s recommendable indeed to only create one instance of the Context class. Context instances are lightweight, but operations like transactions are centrally controlled by this class. QueryProcessor are usually created anew for each query evaluation.
Number of jobs… Just start in the Context class and follow the JobPool reference. Via the
PARALLEL option [1], you can set a maximum limit of parallel database transactions. If you want to enforce that there are never more than transactions running, you can set FAIRLOCK [2] to true.
I’ve just updated the description of the PARALLEL option to indicate what has changed since the introduction of the FAIRLOCK option.
Hope this helps,
Christian
[1] http://docs.basex.org/wiki/Options#PARALLEL
[2] http://docs.basex.org/wiki/Options#FAIRLOCKQuoted text · George Sofianos · 17 lines
On Tue, Jul 11, 2017 at 11:36 AM, George Sofianos <gsf.greece at gmail.com> wrote: > Hello, > > I'm building a web service that along with some other things (XML > Validation, Saxon XQuery, etc) includes a BaseX processor for running XQuery > scripts. I'm wondering what is the best way to use an embedded BaseX > processor. Can some objects be shared (e.g Context, QueryProcessor), or are > they very lightweight and there is no need to share / reuse ? > Can I get the number of the jobs running and the job status like in the > client / server mode? My intention is to make sure I can limit the amount of > the jobs running in parallel, and have more control over the execution > (maybe cancel jobs if necessary) > > Thanks, > > George >
GS
George Sofianos11 Jul 2017 14:08 #
This is exactly what I was looking for, thanks!
George
Quoted text · Christian Grün · 42 lines
On 07/11/2017 03:02 PM, Christian Grün wrote: > Hi George, > > It’s recommendable indeed to only create one instance of the Context > class. Context instances are lightweight, but operations like > transactions are centrally controlled by this class. QueryProcessor > are usually created anew for each query evaluation. > > Number of jobs… Just start in the Context class and follow the JobPool > reference. Via the PARALLEL option [1], you can set a maximum limit of > parallel database transactions. If you want to enforce that there are > never more than transactions running, you can set FAIRLOCK [2] to > true. > > I’ve just updated the description of the PARALLEL option to indicate > what has changed since the introduction of the FAIRLOCK option. > > Hope this helps, > Christian > > [1] http://docs.basex.org/wiki/Options#PARALLEL > [2] http://docs.basex.org/wiki/Options#FAIRLOCK > > > > On Tue, Jul 11, 2017 at 11:36 AM, George Sofianos <gsf.greece at gmail.com> wrote: >> Hello, >> >> I'm building a web service that along with some other things (XML >> Validation, Saxon XQuery, etc) includes a BaseX processor for running XQuery >> scripts. I'm wondering what is the best way to use an embedded BaseX >> processor. Can some objects be shared (e.g Context, QueryProcessor), or are >> they very lightweight and there is no need to share / reuse ? >> Can I get the number of the jobs running and the job status like in the >> client / server mode? My intention is to make sure I can limit the amount of >> the jobs running in parallel, and have more control over the execution >> (maybe cancel jobs if necessary) >> >> Thanks, >> >> George >>
BC
I am using BaseX in a multithreaded environment, which is highly transactional. I ended up using a singleton class as the controller and all other threads execute queries against this singleton class. I have successfully implemented an ELR (Electronic Laboratory Reporting) messaging system which is in production. This system runs under JBoss so you should not have any issues using something like Wildfly as an application server.
Carl R Bondeson
IT Analyst 3
Information Technology
Connecticut Department of Public Health
410 Capitol Ave
Hartford, CT 06134
Phone: 860-509-7434
carl.bondeson at ct.gov
Quoted text · Christian Grün · 31 lines
-----Original Message----- From: basex-talk-bounces at mailman.uni-konstanz.de [mailto:basex-talk-bounces at mailman.uni-konstanz.de] On Behalf Of Christian Grün Sent: Tuesday, July 11, 2017 8:02 AM To: George Sofianos <gsf.greece at gmail.com> Cc: basex-talk at mailman.uni-konstanz.de Subject: Re: [basex-talk] Embedded BaseX Hi George, It’s recommendable indeed to only create one instance of the Context class. Context instances are lightweight, but operations like transactions are centrally controlled by this class. QueryProcessor are usually created anew for each query evaluation. Number of jobs… Just start in the Context class and follow the JobPool reference. Via the PARALLEL option [1], you can set a maximum limit of parallel database transactions. If you want to enforce that there are never more than transactions running, you can set FAIRLOCK [2] to true. I’ve just updated the description of the PARALLEL option to indicate what has changed since the introduction of the FAIRLOCK option. Hope this helps, Christian [1] http://docs.basex.org/wiki/Options#PARALLEL [2] http://docs.basex.org/wiki/Options#FAIRLOCK On Tue, Jul 11, 2017 at 11:36 AM, George Sofianos <gsf.greece at gmail.com> wrote: > Hello, > > I'm building a web service that along with some other things (XML > Validation, Saxon XQuery, etc) includes a BaseX processor for running > XQuery scripts. I'm wondering what is the best way to use an embedded > BaseX processor. Can some objects be shared (e.g Context, > QueryProcessor), or are they very lightweight and there is no need to share / reuse ? > Can I get the number of the jobs running and the job status like in > the client / server mode? My intention is to make sure I can limit the > amount of the jobs running in parallel, and have more control over the > execution (maybe cancel jobs if necessary) > > Thanks, > > George >
GS
George Sofianos14 Jul 2017 10:46 #
Hi Carl,
Sorry I forgot to answer, it's always nice to see more opinions and ideas. We already have a system working on a monolithic application deployed in an application server, but I was creating a new context each time just to be sure, and now that I'm moving this on a separate service It was the perfect time to investigate how to make it better :)
I've also worked with the client / server approach and the dockerized version of BaseX, and while both are easy to work with, they don't cover all our needs. I'm hoping to implement an error resilient messaging queue or use reactive streams and make sure network issues won't affect the XQuery scripts execution.
George
Quoted text · Carl · 54 lines
On 07/11/2017 03:11 PM, Bondeson, Carl wrote: > I am using BaseX in a multithreaded environment, which is highly transactional. I ended up using a singleton class as the controller and all other threads execute queries against this singleton class. I have successfully implemented an ELR (Electronic Laboratory Reporting) messaging system which is in production. This system runs under JBoss so you should not have any issues using something like Wildfly as an application server. > > Carl R Bondeson > IT Analyst 3 > Information Technology > Connecticut Department of Public Health > 410 Capitol Ave > Hartford, CT 06134 > Phone: 860-509-7434 > carl.bondeson at ct.gov > > > > -----Original Message----- > From: basex-talk-bounces at mailman.uni-konstanz.de [mailto:basex-talk-bounces at mailman.uni-konstanz.de] On Behalf Of Christian Grün > Sent: Tuesday, July 11, 2017 8:02 AM > To: George Sofianos <gsf.greece at gmail.com> > Cc: basex-talk at mailman.uni-konstanz.de > Subject: Re: [basex-talk] Embedded BaseX > > Hi George, > > It’s recommendable indeed to only create one instance of the Context class. Context instances are lightweight, but operations like transactions are centrally controlled by this class. QueryProcessor are usually created anew for each query evaluation. > > Number of jobs… Just start in the Context class and follow the JobPool reference. Via the PARALLEL option [1], you can set a maximum limit of parallel database transactions. If you want to enforce that there are never more than transactions running, you can set FAIRLOCK [2] to true. > > I’ve just updated the description of the PARALLEL option to indicate what has changed since the introduction of the FAIRLOCK option. > > Hope this helps, > Christian > > [1] http://docs.basex.org/wiki/Options#PARALLEL > [2] http://docs.basex.org/wiki/Options#FAIRLOCK > > > > On Tue, Jul 11, 2017 at 11:36 AM, George Sofianos <gsf.greece at gmail.com> wrote: >> Hello, >> >> I'm building a web service that along with some other things (XML >> Validation, Saxon XQuery, etc) includes a BaseX processor for running >> XQuery scripts. I'm wondering what is the best way to use an embedded >> BaseX processor. Can some objects be shared (e.g Context, >> QueryProcessor), or are they very lightweight and there is no need to share / reuse ? >> Can I get the number of the jobs running and the job status like in >> the client / server mode? My intention is to make sure I can limit the >> amount of the jobs running in parallel, and have more control over the >> execution (maybe cancel jobs if necessary) >> >> Thanks, >> >> George >>
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