An example of a Haystack search index

from haystack import indexes
from exhibition.models import Exhibition


class ExhibitionIndex(indexes.SearchIndex, indexes.Indexable):
    text = indexes.EdgeNgramField(document=True, use_template=True)
    home_text = indexes.EdgeNgramField(use_template=True)
    name = indexes.CharField(model_attr='name')
    venue_pk = indexes.IntegerField(model_attr='venue__pk')
    city_pk = indexes.IntegerField(model_attr='venue__city__pk', null=True)
    url_slug = indexes.CharField()
    approved = indexes.CharField()
    country_pk = indexes.CharField()
    continent_pk = indexes.CharField()
    industry_pks = indexes.MultiValueField()
    organization_pks = indexes.MultiValueField()
    tag_names = indexes.MultiValueField()
    start_date = indexes.DateField(model_attr='start_date', null=True)
    end_date = indexes.DateField(model_attr='end_date', null=True)

    def prepare_url_slug(self, exhibition):
        return exhibition.url_slug

    def prepare_approved(self, exhibition):
        # had to use string instead of booleans due to a elasticsearch gotcha
        # http://stackoverflow.com/questions/24659326/ngramfield-not-working-if-booleanfield-is-present-haystack-elasticsearch-wi
        return 'True' if exhibition.approved else 'False'

    def prepare_tag_names(self, exhibition):
        return [t.name for t in exhibition.tags.all()]

    def prepare_industry_pks(self, exhibition):
        return [i.pk for i in exhibition.industries.all()]

    def prepare_organization_pks(self, exhibition):
        return [o.pk for o in exhibition.organizations.all()]

    def prepare_country_pk(self, exhibition):
        # Due to a elasticsearch strange behavior, queries containing the word
        # "IT", which is the primary key of the Country "Italy" were failing,
        # so I had to add some underscodes
        if exhibition.venue and exhibition.venue.city:
            return "_%s_" % exhibition.venue.city.country_id
        else:
            return None

    def prepare_continent_pk(self, exhibition):
        # Due to a elasticsearch strange behavior, queries containing the word
        # "AS", which is the primary key of the Continent "Asia" were failing,
        # so I had to add some underscodes
        if exhibition.venue and exhibition.venue.city:
            return "_%s_" % exhibition.venue.city.country.continent.pk
        else:
            return None

    def get_model(self):
        return Exhibition