can't match digits in haystack elastic search - elasticsearch

Question

I have some products that I'm indexing that go something like "99% chocolate". If I search for chocolate, it matches this particular item, but if I search for "99", it doesn't match. I came across this Using django haystack autocomplete with elasticsearch to search for digits/numbers? which had the same issue, but nobody has answered his question. Can someone please help?
Edit2: I'm sorry I neglected to include an important detail. The numeric search itself works, but the autocomplete doesn't work. I'm including the relevant lines:
#the relevant line in my index
name_auto = indexes.EdgeNgramField(model_attr='name')
#the relevant line in my view
prodSqs = SearchQuerySet().models(Product).autocomplete(name_auto=request.GET.get('q', ''))
Edit: following are the results of running the analyser:
curl -XGET 'localhost:9200/haystack/_analyze?analyzer=standard&pretty' -d '99% chocolate'
{
"tokens" : [ {
"token" : "99",
"start_offset" : 0,
"end_offset" : 2,
"type" : "<NUM>",
"position" : 1
}, {
"token" : "chocolate",
"start_offset" : 4,
"end_offset" : 13,
"type" : "<ALPHANUM>",
"position" : 2
} ]
}

Answer 1

finally found the answer here: ElasticSearch: EdgeNgrams and Numbers
Add the following classes and change the Engine under Haystack_connections in settings file to use CustomElasticsearchSearchEngine below instead of default haystack one:
class CustomElasticsearchBackend(ElasticsearchSearchBackend):
"""
The default ElasticsearchSearchBackend settings don't tokenize strings of digits the same way as words, so they
get lost: the lowercase tokenizer is the culprit. Switching to the standard tokenizer and doing the case-
insensitivity in the filter seems to do the job.
"""
def __init__(self, connection_alias, **connection_options):
# see https://stackoverflow.com/questions/13636419/elasticsearch-edgengrams-and-numbers
self.DEFAULT_SETTINGS['settings']['analysis']['analyzer']['edgengram_analyzer']['tokenizer'] = 'standard'
self.DEFAULT_SETTINGS['settings']['analysis']['analyzer']['edgengram_analyzer']['filter'].append('lowercase')
super(CustomElasticsearchBackend, self).__init__(connection_alias, **connection_options)
class CustomElasticsearchSearchEngine(ElasticsearchSearchEngine):
backend = CustomElasticsearchBackend

Answer 2

Running you string 99% chocolate through the standard analyser gives the right results (99 is a term on its own), so if you're not using it currently, you should switch to it.
curl -XGET 'localhost:9200/myindex/_analyze?analyzer=standard&pretty' -d '99% chocolate'
{
"tokens" : [ {
"token" : "99",
"start_offset" : 0,
"end_offset" : 2,
"type" : "<NUM>",
"position" : 1
}, {
"token" : "chocolate",
"start_offset" : 4,
"end_offset" : 13,
"type" : "<ALPHANUM>",
"position" : 2
} ]
}