When will a CardinalityAggregationBuilder Aggregation type be supported in Rollup?

[Paul_Ainslie]

Any idea when CardinalityAggregationBuilder will be supported in Rollups? This query doesn't work against a rolled up index.

Query:

{
  "size": 0,
  "query": {
    "bool": {
      "must": [
        {
          "range": {
            "@timestamp": {
              "gte": "2018-03-01",
              "lte": "2018-03-10T23:59:59.999Z"
            }
          }
        },
        { "term": { "account": "27937601" } }
      ]
    }
  },
  "aggs": {
    "total_bytes": { "sum": { "field": "bytes" } },
    "streams": {
      "terms": {
        "field": "stream",
        "order": { "bytes_sum": "desc" },
        "size": 20
      },
      "aggs": {
        "bytes_sum": { "sum": { "field": "bytes" } },
        "distinct_ips": { "cardinality": { "field": "clientip_n_agent" } }
      }
    }
  }
}

Error:

{
  "error": {
    "root_cause": [
      {
        "type": "illegal_argument_exception",
        "reason": "Unable to translate aggregation tree into Rollup.  Aggregation [distinct_ips] is of type [CardinalityAggregationBuilder] which is currently unsupported."
      }
    ],
    "type": "illegal_argument_exception",
    "reason": "Unable to translate aggregation tree into Rollup.  Aggregation [distinct_ips] is of type [CardinalityAggregationBuilder] which is currently unsupported."
  },
  "status": 400
}

[polyfractal (Zachary Tong)]

Unsure, there are some technical challenges which make it a longer project to support than other metrics. I'll be meaning to open a ticket to track progress on Cardinality/Percentiles... will update the thread in a little bit with a link to the issue.

We definitely want to support it (e.g. it's on the roadmap), but we're not sure when it will be implemented.

[polyfractal (Zachary Tong)]

Just made an issue to track this: https://github.com/elastic/elasticsearch/issues/33214