On 8. des. 2009, at 00.29, Grant Ingersoll wrote: > On Dec 7, 2009, at 3:51 PM, Chris Hostetter wrote: >> ASs someone with very little knowledge of Solr Cell and/or Tika, I find >> myself wondering if ExtractingRequestHandler would make more sense as an >> extractingUpdateProcessor -- where it could be configured to take take >> either binary fields (or string fields containing URLs) out of the >> Documents, parse them with tika, and add the various XPath matching hunks of >> text back into the document as new fields. >> >> Then ExtractingRequestHandler just becomes a handler that slurps up it's >> ContentStreams and adds them as binary data fields and adds the other >> literal params as fields. >> >> Wouldn't that make things like SOLR-1358, and using Tika with URLs/filepaths >> in XML and CSV based updates fairly trivial? > > It probably could, but am not sure how it works in a processor chain. > However, I'm not sure I understand how they work all that much either. I > also plan on adding, BTW, a SolrJ client for Tika that does the extraction on > the client. In many cases, the ExtrReqHandler is really only designed for > lighter weight extraction cases, as one would simply not want to send that > much rich content over the wire.
Good match. UpdateProcessors is the way to go for functionality which modifiy documents prior to indexing. With this, we can mix and match any type of content source with other processing needs. I think it can be neneficial to have the choice to do extration on the SolrJ side. But you don't always have that choice, if your source is a crawler without built-in Tika, some base64 encoded field in an XML or some other random source, you want to do the extraction at an arbitrary place in the chain. Examples: Crawler (httpheaders, binarybody) -> TikaUpdateProcessor (+title, +text, +meta...) -> index XML (title, pdfurl) -> GetUrlProcessor (+pdfbin) -> TikaUpdateProcessor (+text, +meta) -> index DIH (city, street, lat, lon) -> LatLon2GeoHashProcessor (+geohash) -> index I propose to model the document processor chain more after FAST ESP's flexible processing chain, which must be seen as an industry best practice. I'm thinking of starting a Wiki page to model what direction we should go. -- Jan Høydahl - search architect Cominvent AS - www.cominvent.com
