Re: [wildfly-dev] Favour jboss-persistence.xml if present

On 1/29/14, 3:20 PM, Scott Marlow wrote: > On 01/29/2014 03:17 PM, Jason Greene wrote: >> >> On Jan 29, 2014, at 2:11 PM, Scott Marlow <smarlow(a)redhat.com&gt; wrote: >> >>> On 01/29/2014 02:44 PM, David M. Lloyd wrote: >>>> On 01/29/2014 01:39 PM, Klein, Christopher wrote: >>>>> Hey guys, >>>>> I already filled out a feature request in JIRA (https://issues.jboss.org/browse/WFLY-2816). >>>>> >>>>> We have the situation that our development environment (currently JBoss AS 7.1.1) differs from the production instance (WebSphere 8.5). Our persistence.xml has to be adjusted for production environment: different jta-data-source, different properties. The dirty solution for this problem would be to generate separate build artifacts for both environments. As you can imagine I don't like the idea of having two binaries just because of a few different settings. Other options (WildFly or WebSphere specific JPA properties; extending Hibernate persistence provider) do not work. >>>>> >>>>> A much nicer solution would be: WildFly checks on deployment process for the existence of a jboss-persistence.xml. If it does, the jboss-persistence.xml is used for configuring the JPA subsystem. Otherwise it falls back to the standard persistence.xml. The jboss-persistence.xml would use the XML schema from persistence.xml. >>>>> >>>>> I lookup into the WildFly sources and this change should be an easy patch which I would provide. >>>>> >>>>> So here are my questsions: >>>>> 1. Are you generally interested in accepting such a pull request or is it a feature you don't want? >>>>> 2. Does another solution exists to my problem apart from generating different artifacts which makes this pull request needless? >>>> >>>> It sounds like a reasonable idea that actually applies generally. If I >>>> recall correctly, we have something of a mix today of descriptors which >>>> override versus supplementing existing configuration. But overall the >>>> unofficial policy for new descriptors has been to add them in to >>>> jboss-all.xml as subdescriptors, FWIW. >>>> >>> >>> I'm not sure that jboss-all.xml would be a good place for the >>> persistence unit definitions. >> >> I would agree that this is probably impractical. >> >>> >>> I think that the proposed jboss-persistence.xml (or >>> wildfly-persistence.xml) could be helpful for anyone that wants to only >>> develop on WildFly but deploy on other application servers. I suppose >>> this could help someone that wants to migrate off of WildFly as well (to >>> prepare for a switch to something else). Is that what you mean by the >>> proposed solution applying generally? >> >> It does sound a lot like a vendor specific alt-dd feature. We have some other solutions as well that might be relevant: >> >> 1) Deployment overlay feature - This allows you to override the descriptors in a deployment without modifying the deployment. These are added in a separate management op with a match pattern, and preserved outside the lifecycle of the deployment. Available in WildFly 8 and EAP 6.2 (can’t recall if it made EAP 6.1). > > I was just reading > https://docs.jboss.org/author/display/WFLY8/Deployment+Overlays but I'm > not sure that would help with this use case. Since the deployment will > fail due to the persistence.xml targeting WebSphere (persistence unit > property "hibernate.transaction.manager_lookup_class" is set to > "org.hibernate.transaction.WebSphereExtendedJTATransactionLookup"). > The persistence.xml that is the deployment overlay would not include those settings. The deployment overlay feature hides the original persistence.xml in the deployment archive from the deployment processors; they only see the overlay.

> What might help is if we could ignore (or auto-magically remove during > deployment) certain persistence unit property settings that we know will > cause the deployment to fail. > >> >> 2) Property Substituion - There is a flag you can optionally enable in standalone/domain.xml that allows descriptors to contain property expressions. However, this only works for this use case if all venders are using the same expression language (unlikely). I just thought I would mention it. >> >> >>> >>> >>> >>> >>> _______________________________________________ >>> wildfly-dev mailing list >>> wildfly-dev(a)lists.jboss.org >>> https://lists.jboss.org/mailman/listinfo/wildfly-dev >> >> -- >> Jason T. Greene >> WildFly Lead / JBoss EAP Platform Architect >> JBoss, a division of Red Hat >> > > _______________________________________________ > wildfly-dev mailing list > wildfly-dev(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/wildfly-dev >