Bucket_script aggregation on filters aggregation not showing results

[Anton_Pirker]

Hello!

I have "event" (like clicks on websites) documents in a index. Now I want to to calculate the ratio between events with name=x and events with name=y. I use a bucket_script aggregation for that, but the result of it is not shown in the output...

Here is my query:

    GET /_search 
    {
      "query": { ... },
      "aggs": {
        "all_my_documents": {
          "filters": {
            "filters": {
              "all": { "match_all": {} }
            }
          }, 
          "aggs": {

            "bucket-aggregation-for-clicks-per-conversation": {
              "filters": {
                "filters": {
                  "presentation-clicks": { "term" : { "name" : "presentation-anchor-click" }},
                  "conversation-starts": { "term" : { "name" : "conversation-start" }}
                }
              }
            }, 
            "how-many-clicks-per-conversation": {
              "bucket_script": {
                  "buckets_path": {
                      "my_clicks": "bucket-aggregation-for-clicks-per-conversation['presentation-clicks']>_count", 
                      "my_starts": "bucket-aggregation-for-clicks-per-conversation['conversation-starts']>_count"
                  },
                  "script": "params.my_clicks / params.my_starts"
              }
            }

          }
        }
        
      }
    }

The query runs and as a result I get my two buckets but the "how-many-clicks-per-conversation" script does not seem to be run at all, because the value is missing from the output:

    ...
    "aggregations" : {
      "all_my_documents" : {
        "buckets" : {
          "all" : {
            "doc_count" : 5,
            "bucket-aggregation-for-clicks-per-conversation" : {
              "buckets" : {
                "conversation-starts" : {
                  "doc_count" : 4
                },
                "presentation-clicks" : {
                  "doc_count" : 1
                }
              }
            }
          }
        }
      }
    }

So, why is my bucket_script not showing up in the output? Every help is greatly appreciated!

Thanks in advance
Anton