Re: Configuration extension

[Fabio Martelli <fa...@gmail.com>]

Il giorno 29/ago/2012, alle ore 09.39, Fabio Martelli ha scritto:

> 
> Il giorno 28/ago/2012, alle ore 16.51, Kevin Sutter ha scritto:
> 
>> Hi Fabio,
>> It all depends on how extensible of a solution you are looking for.  Are
>> you looking to just extend a current OpenJPA implementation and then
>> migrating those necessary changes from release to release (as your needs
>> required)?  Or, are you looking to provide a pluggable configuration which
>> would make it easier to grow with the OpenJPA releases (but requires a bit
>> more work up-front)?  That's part of the analysis of the requirements that
>> you'll have to do.
> 
> Hi Kevin,
> you are right, I have to "contextualize" my requirement.
> 
> I have to extend OpenJPA in order to add support for SQLAzure [1].
> Please, take a look at [2] and [3].
> 
> As you can imagine, I need to specify some configuration parameters in order to achieve my goal.
> This is the purpose of my request (OpenJPA configuration extension).
> 
> Of course, the best would be to put our developments embedded into OpenJPA (more or less like done for slices - taken as reference for my development) and I hope it will happen sooner or later. Unfortunately, I need something working fine in a very short time so I had to search for a different (but clean) solution.
> 
> The idea is to develop a library of OpenJPA pluggable components and, after a short consolidation period, to submit a patch.
> 
> What do you think about? Am I on the right path?

Hi Kevin,
this is may simple solution to extend OpenJPA configuration.
http://blog.tirasa.net/blogs/index.php/wiseit/

Thank you for you support.
Best regards,
F.

> 
> Best regards,
> F.
> 
> [1] http://en.wikipedia.org/wiki/SQL_Azure
> [2] https://github.com/Tirasa/protojpasqlazure
> [3] https://github.com/Tirasa/OpenJPASQLAzure
> 
>> As you have probably noticed, OpenJPA itself has already extended the
>> OpenJPAConfigurationImpl with both the JDBCConfigurationImpl and the
>> XMLConfigurationImpl.  (As an aside, WebSphere has also extended this
>> implementation for their own extensions.)  So, the capability is there.
>> It's just a matter of how much effort you want to put into it.
> 
> 
>> 
>> Good luck,
>> Kevin
>> 
>> On Tue, Aug 28, 2012 at 6:17 AM, Fabio Martelli <fa...@gmail.com>wrote:
>> 
>>> 
>>> Il giorno 27/ago/2012, alle ore 18.44, Kevin Sutter ha scritto:
>>> 
>>>> Hi Fabio,
>>>> Unfortunately, OpenJPA doesn't have great documentation for extending the
>>>> configuration.  Although, in practice, it is quite easy to do.  What I
>>>> would suggest doing is "implement by example" and look at how other
>>>> configuration properties were incorporated.  For example, let's just take
>>>> openjpa.datacache as an example.  All of the configuration properties
>>> use a
>>>> "plugin configuration" [1].  Then, if you look at the
>>>> OpenJPAConfigurationImpl class, you'll see how this openjpa.datacache is
>>>> parsed and configured.  From there, these configuration values are used
>>>> through out the code (grep for "dataCachePlugin" as an example).
>>>> 
>>>> Hope this helps get you started.
>>> 
>>> Hi Kevin, thank you for your prompt replay.
>>> I sow that OpenJPA configuration is not pluggable.
>>> It seems that, the only way to replace the configuration impl (in order to
>>> add new parameters) it to specify a new BrokerFactory (maybe extending
>>> JDBCBrokerFactory) overriding the single static method newInstance(...).
>>> 
>>> Please, let me know what you think about this solution.
>>> 
>>> Thank you in advance.
>>> Best regards,
>>> F.
>>> 
>>>> Kevin
>>>> 
>>>> [1]
>>>> 
>>> http://openjpa.apache.org/builds/latest/docs/docbook/manual.html#ref_guide_conf_plugins
>>>> 
>>>> On Fri, Aug 24, 2012 at 10:32 AM, Fabio Martelli
>>>> <fa...@gmail.com>wrote:
>>>> 
>>>>> Hi All,
>>>>> I'd like to extend OpenJPA configuration in order to add some custom
>>>>> parameters into my persistence.xml.
>>>>> 
>>>>> Could you give me the best practice to do this?
>>>>> 
>>>>> Thank you in advance.
>>>>> Best regards,
>>>>> F.
>>> 
>>> 
>