Drupal Search Behavior

Question

I looked into the DP 6 search API and did not see a hook that would let me alter the search keys before they are passed into the search module to execute the search. I want to do keyword expansion on the string that the user entered. For instance, if the user entered 'foo', I want to execute a search for 'foo' and 'bar'. There should ultimately be a UI for these mappings, but for a quick prototype I can hardcode the strings.

Where would you start putting code that does this? Did I miss a hook in the search API?

Answer 1

The Synonyms module does this for taxonomy terms. I still may need to do this for full-text search terms. Any suggestions?

Answer 2

I haven't tried this, but after reading the docs I think that you can implement hook__search() in your module, do the keword expansion there and then do a do__search() with the expanded keys.

By the looks of it you would also have to do hook__update__index() too.

Answer 3

The hook to use in this case is hook_search_preprocess. It allows you to edit the keys a user enters before a search is done. Beneficially, it also does this for text being indexed so you get the advantage of expansions on those words for the text being indexed as well.