Low Search

Creating your own Low Search Filter

Creating your own filter is easy. From version 3.2.0 and up, Low Search boasts a simple custom filter API that you can use to create custom filters for your searching needs. These filters can be stand-alone, or you can add them to your own add-ons. Low Search uses this API itself for its native filters.

All filters are executed one after another and each filter passes its search results — consisting of Entry IDs — on to the next. As soon as a filter ends up with an empty set, No Results is triggered, skipping all next filters.

File structure

Filters live in a filters folder inside your add-on package. So, say you’ve created a filter called foo, Low Search will be looking for /my_addon/filters/foo/lsf.foo.php. That name should be unique, so be aware of already existing filters. You can have multiple custom filters in your filters folder.

Naming convention

Inside the lsf.foo.php file should be a class called Low_search_filter_foo which extends Low_search_filter:

class Low_search_filter_foo extends Low_search_filter {}