See parent ticket and kickoff meeting notes.
This ticket is to implement custom buckets for number variables. The user should be able to set the width of the buckets as well as the x-axis offset. For more context, see the meeting notes here: https://confluence.camunda.com/display/CO/2020-05-25+Custom+Buckets+Follow+Up
If the user sets an x-axis offset that exceeds the min. variable value (leading to an invalid range for the aggregations), we return an aggregation that starts at the min. variable value (instead of the set x-axis offset). It would be good to then also display a warning that the x-axis offset has been ignored and why.
- the report configuration includes information on how to group number Variables
- If no explicit custom bucket config is set, calculate an appropriate width and start the x-axis at the first variable value
- the following edge cases need to be covered:
- the report has no instances
- the report has only one instance
- all instances in the report share the same singular number variable value
- the bucket size leads to a bucket amount greater than the ES bucket limit
- the x-axis offset is equal or greater to the max. number variable value
- reports are only combinable when their xAxisOffset and bucket size match