Aggregations: always include item (even if zero results)

[LEDfan]

Hi

I'm building a Faceted search using ElasticSearch and python (http://elasticsearch-dsl.readthedocs.io/en/latest/). I'm using aggregations for this. Everything is working fine, except one issue: if the user selects an option, this option must stay selected, even if it's filtered out because there are options with a higher count.

I didn't found a way to do this, so I added an extra aggregation which only fetches the selected option:

POST question/question/_search
{
   "aggs": {
      "_selected_filter_status": {
         "aggs": {
            "status": {
               "terms": {
                  "field": "status.keyword",
                  "min_doc_count": 0,
                  "include": [
                     "9",
                     "11"
                  ]
               }
            }
         },
         "filter": {
            "terms": {
               "nonprofit.name.keyword": [
                  "xxxxx"
               ]
            }
         }
      }
   },
   "query": {
      "match_all": {}
   }
}

The result is:

 "aggregations": {
      "_selected_filter_status": {
         "doc_count": 1,
         "status": {
            "doc_count_error_upper_bound": 0,
            "sum_other_doc_count": 0,
            "buckets": [
               {
                  "key": "9",
                  "doc_count": 1
               }
            ]
         }
      }
   }

So as you see there is no bucket for status "11". Any idea why elastic does this, or how I can solve this?

Thanks in advance