Rollup searches based on "obsolete" timezones fail

[cjcenizal]

This originated from https://discuss.elastic.co/t/visualizing-rollup-index-with-timezone-result-in-error/159064/2. CC @polyfractal

To reproduce, follow these steps to create data, a rollup job, and a search on the rolled-up data:

PUT test_index

PUT test_index/_doc/1
{
  "utc_time" : "2018-12-02T16:02:19.851Z"
}

PUT _xpack/rollup/job/test_job
{
    "index_pattern": "test_index",
    "rollup_index": "test_index_rollup",
    "cron": "0 * * * * ?",
    "groups": {
      "date_histogram": {
        "interval": "24h",
        "field": "utc_time",
        "time_zone": "Canada/Mountain"
      }
    },
    "metrics": [],
    "page_size": 1000
}

POST _xpack/rollup/job/test_job/_start

GET test_index_rollup/_rollup_search
{  
   "size":0,
   "aggregations":{  
      "2":{  
         "date_histogram":{  
            "field":"order_date",
            "interval":"24h",
            "time_zone":"Canada/Mountain",
            "min_doc_count":1
         }
      }
   }
}

The search will fail with this error:

{
  "error": {
    "root_cause": [
      {
        "type": "illegal_argument_exception",
        "reason": "There is not a rollup job that has a [date_histogram] agg on field [order_date] which also satisfies all requirements of query."
      }
    ],
    "type": "illegal_argument_exception",
    "reason": "There is not a rollup job that has a [date_histogram] agg on field [order_date] which also satisfies all requirements of query."
  },
  "status": 400
}

[elasticmachine]

Pinging @elastic/es-analytics-geo

[polyfractal]

Right, I see the issue. The timezone in use here (Canada/Mountain) and in the discuss issue (Japan) are "obsolete" timezones and have been replaced by America/Edmonton / Asia/Tokyo respectively.

What's happening is that internally the date_histogram is converting the TZ on the fly to the "new" timezone, but rollup is comparing it against the original. So it's seeing America/Edmonton != Canada/Mountain and failing to run the query because the timezones don't match.

I think this is fixable in a bwc manner, will work on a PR.