Hi all, The main issue we currently have with our full text indexers is that Lucene and Solr are not "OSGi ready", missing proper MANIFEST entries so that they cannot directly be installed in e.g. Apache Felix, don't have semantic version information, etc.
Currently oak-lucene embeds the Lucene dependencies it needs, also exporting its Lucene packages so that they can be used by oak-solr-core (as they're needed by Solr) which exposes its embedded Solr packages so that oak-solr-[embedded|remote] can use them. While this should work, there are some concerns raised in OAK-1442 [2]: - one issue is that with the current approach we have a problem if a Lucene / Solr package changes in a backward incompatible way while we don't properly upgrade the semantic version of the Oak package(s) using that, which in the end would mean that we in Oak would have to track changes in Lucene / Solr and I think I can assume we don't want to - the other issue relates more to how we package such Lucene and Solr artifacts to use them, as the suggestion is to just wrap o.a.lucene-* and o.a.solr-* in two wrapping bundles which can be installed inside an OSGi container. in OAK-1475 [1] we discussed a bit some different approaches for the deployment of Oak Lucene and Solr indexers in an OSGi environment, currently we have the following options: 1. package oak-lucene and oak-solr-* in a single bundle (e.g. called oak-fulltext), with their Lucene and Solr dependencies embedded, the Lucene indexer OSGi services would be already available, the Solr ones would need to be configured in order to start the Solr indexer. 2. package and export Lucene stuff in a oak-lucene-osgi bundle, package and export Solr stuff in oak-solr-osgi bundle, avoid oak-lucene and oak-solr-core to export Lucene and Solr packages. 3. merge oak-solr-* in a single oak-solr bundle which embeds the Solr dependencies (but doesn't export them) to be a fragment of oak-lucene (so that they share the classloader and therefore oak-solr can use Lucene stuff in oak-lucene), move the OSGi services we need for Solr in Oak into oak-solr-osgi (as a fragment cannot run OSGi components/services) Not yet discussed options: 4. remove the exported contents from oak-lucene and oak-solr, merge oak-solr-* together and duplicate the Lucene dependencies to be embedded in oak-solr. Options 1 and 4 are the simplest ones, the only disadvantage is packaging is heavy (in 4 we have duplicated embedded dependencies for Lucene in oak-lucene and oak-solr) Option 2 is the most OSGi oriented, even if has the unlikely, but yet possible, issue with semantic versioning. Option 3 is the smartest and trickiest one, no duplication of dependencies, full OSGi, but a bit more complicated as it uses OSGi fragments. My preferences go to 3 and 4. As this should be fixed for 0.19 please share your comments, Regards, Tommaso [1] : https://issues.apache.org/jira/browse/OAK-1475 [2] : https://issues.apache.org/jira/browse/OAK-1442?focusedCommentId=13908472&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-13908472
