Sphinx search for Discourse

In an interesting turn of events, adding a dependency to something like lucene or sphinx is now not really a huge deal - now that we use Docker for deployment.

That said, full page results must come first, we need to continue refining pg, till we strongly believe it is just too limited for our purposes.

There is a whole unexplored vector (pg_trgm) that needs testing first. I don’t see any reason to jump off the bus before we

  1. Come to a strong understanding of the limitations of the bus
  2. Agree that the bus is too limited