Small improvements on the ES field cap endpoint

[fmassot]

• if one of the index patterns doesn’t match anything, we should return a 200: we should call check_all_index_metadata_found method in the root function (as it's done for a classic search endpoint
• return undocumented type value
• /_field_caps URL

Query Parameters

• fields
• allow_no_indices (ignored)
• expand_wildcards (ignored)
• accept ignore_unavailable query parameter and ignore it silently
• include_unmapped parameter
• types parameter
• filters parameter

[PSeitz]

add a test for the URL _field_caps?=* to catch regression on this one

What regression? _field_caps?=* is an invalid url and returns an error

[fmassot]

@PSeitz yes indeed, we need to fix this.

[PSeitz]

@PSeitz yes indeed, we need to fix this.

What needs to be fixed?

[fmassot]

It would be nice to be able to limit the number of splits we scan.

I see 2 options: limit the number of splits to 1000 by default or to a time window (last 30 days for example).

[PSeitz]

Related Issues
#3527
#4242