Interesting conversation. So if hypothetically Solr's FileFloatSource / ExternalFileField didn't yet exist and we were instead talking about how to implement such a thing on the latest 4.x code, then how basically might it work? I can see how to implement a Solr CodecFactory ( a SchemaAware one) , then a DocValuesProducer. The CodecFactory implements NamedInitializedPlugin and can thus get its config info that way. That's one approach. But it's not clear to me where one would wrap AtomicReader with FilterAtomicReader to use that approach.
~ David Robert Muir wrote > On Sat, Mar 23, 2013 at 7:25 AM, Alan Woodward < > alan@.co > > wrote: >>> I think instead FieldCache should actually be completely package >>> private and hidden behind a UninvertingFilterReader and accessible via >>> the existing AtomicReader docValues methods. >> >> Aha, right, because SegmentCoreReaders already caches XXXDocValues >> instances (without using WeakReferences or anything like that). >> >> I should explain my motivation here. I want to store various scoring >> factors externally to Lucene, but make them available via a ValueSource >> to CustomScoreQueries - essentially a generalisation of FileFloatSource >> to any external data source. FFS already has a bunch of code copied from >> FieldCache, which was why my first thought was to open it up a bit and >> extend it, rather than copy and paste again. >> >> But it sounds as though a nicer way of doing this would be to create a >> new DocValuesProducer that talks to the external data source, and then >> access it through the AR docValues methods. Does that sound plausible? >> Is SPI going to make it difficult to pass parameters to a custom >> DVProducer (data location, host/port, other DV fields to use as primary >> key lookups, etc)? >> > > its not involved if you implement via FilterAtomicReader. its only > involved for reading things that are actually written into the index. > > --------------------------------------------------------------------- > To unsubscribe, e-mail: > dev-unsubscribe@.apache > For additional commands, e-mail: > dev-help@.apache ----- Author: http://www.packtpub.com/apache-solr-3-enterprise-search-server/book -- View this message in context: http://lucene.472066.n3.nabble.com/Opening-up-FieldCacheImpl-tp4050537p4051217.html Sent from the Lucene - Java Developer mailing list archive at Nabble.com. --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org
