[Vis Default editor] Fix issue with Rollup

[maryia-lapata]

Summary

1. There is an issue with Rollup Index pattern. When Date Histogram agg is selected, the code is broken and Buckets group disappeared:

2. I found one more issue. Rollup Index pattern -> Date Histogram -> interval control should be set in 1m (default value from Editor Config of Rollup), but it's set in auto (due to the hook is launched before editorConfig is changed)

What was done:

• Reverted fieldsFetcher.fetch to fieldsFetcher.fetchForWildcard for displaying correct Time Filter field name during Rollup Index Pattern creation (instead of timestamp.date_histogram.timestamp):

  

• Added a condition for the effect which sets default params from editor config (it resolves 2).

• When getInterval is invoked with undefined value (e.g. when a user cleans the interval field), for Rollup Index Pattern esInterval is calculated based on original value (undefined) rather than default value (auto) as for simple Index pattern. It causes an exeption in parseEsInterval. That's why now makeLabel is called safety.

With the changes:

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[elasticmachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request

[elasticmachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request

[maryia-lapata]

After some debugging I found out that the root cause is deeper.
What we see: The method makeLabel breaks with the error 'field' is required.
The reason: The field should be set to a default value when the agg type is changed. It occurs in agg_config.js. The default value for Date Histogram field is agg.getIndexPattern().timeFieldName (for Rollup index pattern it equals timestamp.date_histogram.timestamp). And then in deserialize method of Field param it tries to get a field object by field name (timestamp.date_histogram.timestamp), but the index pattern doesn't have a field with such name, it has just timestamp field name.

This undefined field causes throwing an error. A default value for field params as well as for other params were not set, which in turn produces the error during getting agg description via makeLabel() call.

Since Rollup index pattern has composite timeFieldName it seems that it should be a different way for getting a field object by timeFieldName for Rollup index pattern.

@jen-huang if you know could you please explain how timeFieldName is formed and why it differs from simple index pattern?

[elasticmachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request

[jen-huang]

@maryia-lapata Rollup documents are special in that they are not "real" documents, the field that you are seeing (timestamp.date_histogram.timestamp) will eventually be mapped to the original time field when the rollup indices are queried by rollup search.

I am seeing an issue when it comes to creating rollup index pattern:

The fields here should already be timestamp, not timestamp.date_histogram.timestamp, I think something got lost with typescript conversion. This might be why you are seeing the same field in visualizations. I'm investigating further..

[jen-huang]

This is the culprit for the rollup index pattern:
ba8a453#diff-d1e2b5c0839b8d02c31d0270350e9387R92

@ppisljar Do you recall why this line was changed from fieldsFetcher.fetchForWildcard to fieldsFetcher.fetch? Is it possible to change this back?

@maryia-lapata I tested replacing that line with:

indexPattern.fieldsFetcher.fetchForWildcard(pattern, getFetchForWildcardOptions())

and the time field is now displaying correctly in visualizations and displaying results:

Could you try adding that change to this fix and see if that unblocks you?

[maryia-lapata]

@jen-huang thank you so much!

I added the fix for Time Filter field name and updated the PR description.

@ppisljar @timroes @jen-huang I'd very appreciate it if you review these changes.

[elasticmachine]

Pinging @elastic/kibana-app

[ppisljar]

i think this was changed by mistake from fetchForWildcard to fetch, while updating the method (before it existed on index pattern service and now its on index pattern and index pattern does not need to be passed in)

[elasticmachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request

[timroes]

Tested on Chrome Linux. Seems to fix all described issues and Code LGTM

[jen-huang]

Tested locally with a rollup pattern with a time field, and one without a time field selected. LGTM!