Term Boost¶
Warning
BIG FAT WARNING
As far as I can see, the term boost functionality is implemented by the specs in the Haystack documentation, however it does not really work as it should!
When applying term boost, results are discarded from the search result, and not re-ordered by boost weight as they should. These are known problems and there exists open issues for them:
Please do not use this unless you really know what you are doing!
(And please let me know if you know how to fix it!)
Term boost is achieved on the SearchQuerySet level by calling SearchQuerySet().boost(). It is
implemented as a drf_haystack.filters.HaystackBoostFilter filter backend.
The HaystackBoostFilter does not perform any filtering by itself, and should therefore be combined with
some other filter that does, for example the drf_haystack.filters.HaystackFilter.
from drf_haystack.filters import HaystackBoostFilter
class SearchViewSet(HaystackViewSet):
...
filter_backends = [HaystackFilter, HaystackBoostFilter]
The filter expects the query string to contain a boost parameter, which is a comma separated string
of the term to boost and the boost value. The boost value must be either an integer or float value.
Example query
/api/v1/search/?firstname=robin&boost=hood,1.1
The query above will first filter on firstname=robin and next apply a slight boost on any document containing
the word hood.
Note
Term boost are only applied on terms existing in the document field.