[BUG] Missing fields in the csv report

[zhongnansu]

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I am trying to create a CSV report based on a saved search that contains fields like @timestamp, A, B, C.D, C.E, F, etc. But the generated file only contains @timestamp, A, B, F - in the report all complex fields are missing.
In fact - the fields that mapped as object in my index are missed.
Why did this happen and how can I fix it?

Kibana v 7.10.0 from docker-image "amazon/opendistro-for-elasticsearch-kibana:1.12.0"

For example:

   {
        "_index" : "my_index",
        "_type" : "_doc",
        "_id" : "789be064-0758-4245-8ca1-6570df3bb5a7",
        "_score" : 1.0,
        "_source" : {
          "status" : "alert",     -   simple field = string
          "issue_uid" : 123,   -   simple field = number
          "created_at" : "2020-09-21T05:02:48.000+03:00",    -   simple field = date
          "alerts_count" : 2,   -   simple field = number
          "labels" : {       -   complex field = object 
            "kubernetes" : "cluster.k8s",    -  part of complex field  -  will be missed from CSV-report
            "statefulset" : "sts1"  -  part of complex field  -  will be missed from CSV-report
          }
        }
    }

This issue is submitted by @uzhinskiy
opendistro-for-elasticsearch/kibana-reports#363

[joshuali925]

This issue is fixed and merged by opendistro-for-elasticsearch/kibana-reports#361. I'm able to reproduce with opendistro-1.13.2.0 but not the latest dev branch. The fix will be included in the next release

[joshuali925]

Edit: I can see the issue now by selecting specific fields that are nested instead of capturing all fields. The issue is caused by the parsing logic in code, and will be fixed when opendistro-for-elasticsearch/kibana-reports#367 gets merged