Parameter to round date histograms up instead of rounding down, to support a right-aligned histogram

[wylieconlon]

I couldn't find any previous issues in Elasticsearch, but it's been a long-standing open issue in Kibana to allow "align to now" instead of "align to round intervals". I appreciate that we documented the rounding last year.

The requirement is that instead of rounding based on the Epoch time, we should allow the user to provide a fixed time to round from. For example:

POST /sales/_search?size=0
{
  "aggs": {
    "sales_over_time": {
      "date_histogram": {
        "field": "@timestamp",
        "fixed_interval": "1h",
        "rounding": {
          "mode": "down",
          "from": "now"
        }
      }
    }
  }
}

So instead of generating buckets at the beginning of each hour, it would generate buckets that align with the time of the request.

[elasticmachine]

Pinging @elastic/es-analytics-geo (Team:Analytics)

[jimczi]

That looks like something that you could implement client-side with the offset parameter of the date_histogram:
https://www.elastic.co/guide/en/elasticsearch/reference/current/search-aggregations-bucket-datehistogram-aggregation.html#search-aggregations-bucket-datehistogram-offset ?

[imotov]

@wylieconlon does this work for you? Should we close this issue or you want to continue?

[wylieconlon]

@imotov Yes, I think this workaround works now that Kibana does datemath conversion in the browser.