Hi Joshua,
that's a limitation of the Scala API.
Row requires to explicitly specify a TypeInformation[Row] but it is not
possible to inject custom types into a CaseClassTypeInfo, which are
automatically generated by a Scala compiler plugin.
The probably easiest solution is to use Flink's Java Tuple classes instead
of a case class.
You can import the Java Tuples with
import org.apache.flink.api.java.tuple.{Tuple2 => JTuple2}
And create a TupleTypeInfo for example with
new TupleTypeInfo(new RowTypeInfo(Types.STRING, Types.LONG), Types.DOUBLE)
Best, Fabian
2017-10-16 23:26 GMT+02:00 Joshua Griffith <jgriff...@campuslabs.com>:
> Correction: I have the row’s RowTypeInfo at runtime before the job starts.
> I don’t have RowTypeInfo at compile time.
>
> On Oct 16, 2017, at 4:15 PM, Joshua Griffith <jgriff...@campuslabs.com>
> wrote:
>
> Hello,
>
> I have a case class that wraps a Flink Row and I’d like to use fields from
> that Row in a delta iteration join condition. I only have the row’s fields
> after the job starts. I can construct RowTypeInfo for the Row but I’m not
> sure how to add that to Flink’s generated type information for the case
> class. Without it, I understandably get the following error because Flink
> doesn’t know the Row’s TypeInformation:
>
> org.apache.flink.api.common.InvalidProgramException: This type
> (GenericType<org.apache.flink.types.Row>) cannot be used as key.
>
>
> Is there a way to manually construct or annotate the type information for
> the case class to provide the Row’s type information so it can be used in a
> join? I could alternately replace the case class with a Tuple and construct
> a TupleTypeInfo but a tuple is more difficult to use than a case class.
>
> Thanks,
>
> Joshua
>
>
>
