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4. See error

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Plugins
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Steps to reproduce:

1. Create a report definition
2. On time range field, use relative ranges eg. "from 7 days ago (round)" and "to now".
3. Save the report definition
4. Reopen it a minute later

Note that since internally the KibanaReports plugin converts the range field from elasticsearch DateMath to ISO duration, it is not able to do some things, for example the "round" option won't work properly.

Since I'm working on a lot of issues that I found on this plugin, reading the code I noticed that it don't use DateMath to store the time range of the report. This makes no sense because ISO duration will not be able to represent the same range selected on the default EuiSuperDatePicker.

I really see no reason for not using DateMath to store the range:

{
  from: "now/d-7d",
  to: "now"
}

This issue was originally submitted by @iget-master
opendistro-for-elasticsearch/kibana-reports#353