Re: [hibernate-dev] HSEARCH-3000 Pick Jigsaw Automatic Module names for all published modules

2018-02-12 19:28 GMT+01:00 Sanne Grinovero <sanne(a)hibernate.org&gt;: > > On 12 February 2018 at 18:00, Gunnar Morling <gunnar(a)hibernate.org&gt; wrote: > > > > > > 2018-02-12 17:55 GMT+01:00 Sanne Grinovero <sanne(a)hibernate.org&gt;: > >> > >> Picking automatic module names for Hibernate Search isn't going to be > >> straight-forward as our two main jars (hibernate-search-engine & > >> hibernate-search-orm) suffer from split package among them. > >> > >> We can't really fix the split package problem without breaking all > >> users, so if we want to consider that, we can debate it but that will > >> need to happen at another round as we're doing a minor release, so > >> let's focus on: > >> # Which names to pick > >> # Should we pick the names at all > >> # Which modules should have a name > >> > >> For a great background on the possible strategies and pitfalls I > >> recommend reading Stephen Colebourne's blog on this subject [1]. > >> He persuaded me there are good reasons to use the "reverse DNS, the > >> top level package", however since we have the split package problem we > >> can't simply go with that. > >> > >> Still, we can respect the principles he recommends with a small > >> variation. It's fair to assume that the `org.hibernate.search` prefix > >> is "ours"; since the nature of the suggestion is focused on making > >> sure there are no misunderstandings in the community about which names > >> you can choose - as there is no central authority making sure module > >> names aren't clashing - we should be fine within Hibernate projects > >> with any `org.hibernate.X` prefix, as long as we coordinate and reach > >> an agreement on this list. > >> > >> So, I propose we use: > >> > >> Engine module: > >> - org.hibernate.search.engine > >> > >> ORM integration module: > >> - org.hibernate.search.orm > >> > > Those names sound good to me. > > > >> > >> JGroups, JMS backends: > >> [ no automatic module name ? Excepting some "guidelines" in the JMS > >> module, these are not public API so nobody would benefit from it - > >> also we think we might want to phase out the name "backend" in the > >> future ] > >> > >> Elasticsearch integration module [hibernate-search-elasticsearch.jar]: > >> - org.hibernate.search.elasticsearch > >> > >> Elasticsearch / AWS security integration: > >> [ no automatic module name: no public API ] > >> > >> Serialization / Avro > >> [ no automatic module name: no public API ] > >> > >> WDYT? > > > > > > The user may still need to reference those modules when launching a > > modularized application. Also if they don't directly declare say the JMS > > backend as a dependence of their own module, they'd still have to > > specify it > > via --add-modules, so to resolve these additional modules and add them > > to > > the module graph. Hence I'd declare automatic module names for these, > > too. > > Good point, I had not thought that our modules wouldn't be able to > load other extensions from classpath. > > >> We could also pick names for the ones which I've listed as "no public > >> API" but I see no point: as we're only assigning an "Automatic Module > >> Name" we won't be able to explicitly state that the other modules > >> depend on these. So nobody will use them, and things are a bit in flux > >> anyway in this area because of Hibernate Search 6 plans. > > > > > > I don't fully understand this paragraph. > > You mostly invalidated it with the previous comment, but what I meant > is that we can't have the `org.hibernate.search.engine` declare a > dependency on any implementation module, as we're not adding a > module-info definition. > > >> Another optional altogether: since we have split packages which we'll > >> have to resolve before we can actually transform these into fully > >> fledged modules, I think an acceptable position is also to say we > >> won't be publishing any automatic module name yet. Personally I'm > >> inclined to go with the names suggested above, at least some others > >> can start making baby steps, even if it's not all there. > > > > > > IMO automatic module names should only be declared after at least some > > basic > > vetting that these modules will actually work when used as modules. If > > that's not the case, I wouldn't add these headers, as users rightfully > > may > > consider their presence as endorsement of using them as modules. > > > > That said, I can't seem to find split packages between engine and orm. > > In > > fact I can launch an application with both of them on the module path > > just > > fine. So there may be no problem actually? > > Interesting, I'm pretty sure we had some. We had several issues > resolved over time to resolve them, I never realized we might have > completed them all. The "line" defining what belongs where is still > blurry though, we should make sure this won't have future regressions. Where I had problems with split packages was when exploring HSearch @ Java 9 modules last year was Lucene. In the version used back then (not sure whether it's still an issue today), there was a split package between Lucene's core and the util module (the one with the uninverting reader). You might take my example project I had created for running ORM as modules (https://github.com/gunnarmorling/hibernate-orm-on-java9-modules/compare/o...) if you're interested in doing the same for HSearch. IIRC, the Lucene split package made me give up back then, it's surely worth taking another look with the current versions in use. > > > I'll see if we can produce fully fledged module-info descriptors then :) > > > > >> > >> # What I don't like: > >> For one, that the typical application will need to import both > >> `org.hibernate.search.engine` and `org.hibernate.search.orm`, and > >> likely more as well (e.g. Elasticsearch API, Lucene API module is > >> coming, ..). > > > > > > I'm not exactly sure what you mean by "import" here. But if it's about > > the > > user having to declare dependences in their module descriptor to > > o.h.s.engine and o.h.s.orm modules, you may consider to make the former > > a > > transitive dependence of the latter once you add actual module > > descriptors: > > > > module org.hibernate.search.orm { > > requires transitive org.hibernate.search.engine; > > ... > > } > > > > That way the user just has to add declare the dependence to o.h.s.orm. > > That's definitely suitable if APIs in o.h.s.orm use types from engine in > > their public API signatures. > > +1 that's the better option. > > My thought was about automatic module names though, but totally > irrelevant if we go for full modules. > > Thanks, > Sanne > > > > >> > >> Maybe similar to BOM's today we could publish a module which > >> statically imports multiple of these, that could be nicer to use but > >> we risk needing to publish (and document) one for each of a selection > >> of combinations. So let's not start with such things yet. > >> > >> Thanks, > >> Sanne > >> > >> [1] http://blog.joda.org/2017/05/java-se-9-jpms-automatic-modules.html > >> _______________________________________________ > >> hibernate-dev mailing list > >> hibernate-dev(a)lists.jboss.org > >> https://lists.jboss.org/mailman/listinfo/hibernate-dev > > > >