Native ElasticSearch suggestion fields using Haystack

search_indexes.py

from haystack import indexes
from haystack.fields import SearchField
from haystack.backends import elasticsearch_backend


class CompletionField(SearchField):
    field_type = 'completion'
    
# As suggested at https://www.elastic.co/guide/en/elasticsearch/reference/current/search-suggesters-completion.html
elasticsearch_backend.FIELD_MAPPINGS['completion'] = {
    "type" : "completion",
    "index_analyzer" : "simple",
    "search_analyzer" : "simple",
    "payloads" : True
}

class MyIndex(indexes.SearchIndex, indexes.Indexable):
    text = indexes.EdgeNgramField(document=True, use_template=True)

    suggest = CompletionField()
    
    def prepare_suggest(self, obj):
        return self.prepared_data['text'].split()