For this to work will require some significant changes. The main one being to combine JPA's support for schema generation along with SchemaManagementTool. The reason being simply that I will need to encapsulate the interpretation of all these settings behind the SchemaManagementTool facade in order for things to properly replace SchemaManagementTool as Gunnar suggests.
I am starting this work now on top of the work Gunnar has already done on the PR he sent[1]. But that work is just the tip of the iceberg. So if you have input to this, speak soon. [1] https://github.com/hibernate/hibernate-orm/pull/1231 On Wed, Jan 20, 2016 at 6:13 AM Gunnar Morling <gun...@hibernate.org> wrote: > I went for the proposed intermediary step to avoid breaking the API of > SchemaManagementTool and its delegates. If you have a way for not > breaking the API or think breaking it is alright, then +1 for doing > the ProperSolution™ in 5.1. > > What would it comprise, changing the delegate methods such as > doCreate() to expect a single parameter object providing all the > required info? Target could be a part of this, just an enum probably, > based on wich delegates would do their thing. If it's that, I can try > and help out with it. > > Regarding the release schedule, I'd personally be fine with pushing it > a bit back, but then I don't know whether there are any other hard > timelines to be met. > > > 2016-01-19 16:25 GMT+01:00 Steve Ebersole <st...@hibernate.org>: > > I'd like to get this work into 5.1. But, as much as possible, I'd like > to > > get the ProperSolution in place rather than just a > StepInTheRightDirection. > > If we need to push this date 2-4 weeks I am ok with that. That would > help > > us coordinate with Infinispan 8.2 schedule (iiuc) for > hibernate-infinispan, > > not to mention I still have to review the work Vlad has done on the docs > > again as well as polish the load-by-multi-id API[1]. > > > > [1] Sanne still waiting on your feedback to the open question of internal > > routing of those calls. > > > > On Tue, Jan 19, 2016 at 8:41 AM Gunnar Morling <gun...@hibernate.org> > wrote: > >> > >> Hi Steve, > >> > >> As discussed on IRC, I tried plugging in my own SchemaManagementTool > >> and delegates and letting them do the initialization work required for > >> OGM. > >> > >> I am hitting a wall though when it comes to the usage in the > >> SchemaExport controller: As it's invoking doCreate() and doDrop() > >> right in the constructor with a "fake" target for delegating the SQL > >> statements, I am bitten by the fact that SchemaExport is instantiated > >> twice in SessionFactoryImpl (once for create, once for drop at > >> shutdown), so I see to invocations to doCreate() and doDrop(). Also I > >> am lacking the knowledge of what's passed as Target for the controller > >> invocation. > >> > >> So I went ahead and changed SchemaExport to invoke SchemaCreator and > >> -Dropper only in execute(), passing them actual Target implementations > >> as it's done in SchemaUpdate, too. It's not yet what you described as > >> the ultimate goal (not looping back to Target), but IMO it's a step > >> into the right direction, not the least making things consistent > >> between SchemaExport and SchemaUpdate and also leaving APIs largely > >> unchanged for the time being. With that I should be able to do it on > >> the OGM side as you suggested, essentially ignoring the > >> Target/Exporter stuff. > >> > >> I've filed ORM PR https://github.com/hibernate/hibernate-orm/pull/1231 > >> for the change. Let me know what you think. > >> > >> Cheers, > >> > >> --Gunnar > >> > >> > >> 2016-01-14 15:51 GMT+01:00 Steve Ebersole <st...@hibernate.org>: > >> > I am not sure I am a big fan of The String->Object change > specifically. > >> > In > >> > theory it sounds great. But there is a major premise in schema > tooling > >> > around the idea of the actions being reduce-able to Strings. That's > >> > important not just for SQL, but for the idea of writing to a file as > >> > well. > >> > It also affects the whole concept of Exporter/Exportable. > >> > > >> > The ultimate design goal here is to unify schema creation and dropping > >> > across native and JPA requirements. I just simply have not had the > time > >> > to > >> > work on that. This would all happen "behind" SchemaManagementTool and > >> > friends. SchemaExport, etc are actually just controllers responsible > >> > for > >> > coordinating the calls into the SchemaManagementTool delegates. The > >> > main > >> > problem at the moment IMO is that Target gets passed into these > >> > SchemaManagementTool delegates. Ideally, and certainly this would fit > >> > with > >> > your case, I think we want SchemaManagementTool or its delegates to > >> > handle > >> > interpreting the "arguments". This was part of the intent of > developing > >> > the "CommandLineArgs" stuff that is used inside SchemaExport, etc now; > >> > the > >> > idea was to encapsulate the settings each tool needs to operate and > >> > isolate > >> > the process of building/interpreting those args. > >> > > >> > The next step I wanted to look at there was to morph CommandLineArgs > >> > into a > >> > more generic "parameter object" for initializing the actual > >> > SchemaManagementTool delegates. > >> > > >> > The idea is that the more we can push into SchemaManagementTool and > its > >> > delegates the more pluggable this entire process becomes. Ultimately, > >> > as I > >> > mentioned above, I just do not think it is feasible for ORM and OGM to > >> > share all of these implementation contracts. Forcing a switch from > >> > String > >> > (the DDL) arguments to some amorphic Object reinforces that in my > mind. > >> > But that would not stop OGM from completely swapping > >> > SchemaManagementTool > >> > and its delegates and simply not using Target, Exporters, etc. > >> > > >> > > >> > On Thu, Jan 14, 2016 at 7:44 AM Gunnar Morling <gun...@hibernate.org> > >> > wrote: > >> > > >> >> Hi Steve, > >> >> > >> >> One thing useful to have for OGM would be a generalization of the > >> >> hbm2ddl tooling so we can re-use it for managing NoSQL databases. Not > >> >> all of them are "schemaless", e.g. Cassandra works with a fixed > >> >> schema, and while MongoDB largely is schemaless, we still want to > >> >> create stuff like indexes in the database. > >> >> > >> >> I took a look and found that SchemaManagementTool as a pluggable > >> >> service already goes halfway into that direction. The issue with it > is > >> >> that I cannot replace the list of exporters used by SchemaExport nor > >> >> the list of tool targets used by SchemaUpdate. Having a pluggable > >> >> service allowing me to customize that with an OGM-specific > >> >> implementation should do the trick. > >> >> > >> >> As per some comments in the code, SchemaExport seems to be in some > >> >> intermediary state, where the ops are not executed directly through > >> >> the targets passed to SchemaCreator/Dropper but are read into String > >> >> arrays which are then passed on to separate exporters. I suppose part > >> >> of that work should be to consolidate this and basically follow the > >> >> same approach as used in SchemaUpdate? > >> >> > >> >> Another facet is that for some OGM grid dialects we'd need another > >> >> representation of commands than Strings, as not all the backends have > >> >> a DDL but expect API invocations for that purpose. For that it'd be > >> >> required to change Target#accept(String) into accept(Object) so we > can > >> >> pass some kind of command object. File exports would only work in a > >> >> limited fashion, but we could live with that. Schema > creation/dropping > >> >> bound to the SF lifecycle is what I am after here. > >> >> > >> >> I'd be willing to work on this once we agree on the general approach. > >> >> > >> >> Any thoughts? > >> >> > >> >> Thanks, > >> >> > >> >> --Gunnar > >> >> > >> >> > >> >> > >> >> 2016-01-13 14:10 GMT+01:00 Guillaume Smet <guillaume.s...@gmail.com > >: > >> >> > On Tue, Jan 12, 2016 at 6:40 PM, Steve Ebersole < > st...@hibernate.org> > >> >> wrote: > >> >> > > >> >> >> If you clean up the conflicts I can look for 5.1 > >> >> >> > >> >> > > >> >> > Done! > >> >> > > >> >> > -- > >> >> > Guillaume > >> >> > _______________________________________________ > >> >> > hibernate-dev mailing list > >> >> > hibernate-dev@lists.jboss.org > >> >> > https://lists.jboss.org/mailman/listinfo/hibernate-dev > >> >> > >> > _______________________________________________ > >> > hibernate-dev mailing list > >> > hibernate-dev@lists.jboss.org > >> > https://lists.jboss.org/mailman/listinfo/hibernate-dev > _______________________________________________ hibernate-dev mailing list hibernate-dev@lists.jboss.org https://lists.jboss.org/mailman/listinfo/hibernate-dev
