NIFI-16069 - PutIcebergRecord fails with ClassCastException when writing complex types (arrays, maps, nested records)

[maltesander]

Summary

NIFI-16069 - PutIcebergRecord fails with ClassCastException when writing complex types (arrays, maps, nested records)

PutIcebergRecord fails to write FlowFiles whose schema contains complex/nested types like Iceberg list, map, or struct columns. RecordConverter only translates top-level scalar values (java.sql timestamp/date/time -> java.time) and passes complex values through unchanged.
As a result, values reach Iceberg's Parquet writer in NiFi's native representation, which is incompatible with what Iceberg expects:

• Nested records arrive as org.apache.nifi.serialization.record.MapRecord but Iceberg requires org.apache.iceberg.StructLike.
• Array fields arrive as Object[] but Iceberg's writer requires a java.util.Collection.
• Maps and elements/values nested inside these types are likewise not converted (e.g. a date inside an array or map value).

Because conversion is gated on scalar field types only, records consisting solely of complex fields skip conversion entirely.

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  • JDK 21
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