An incompatibility between the .NET and Java flight implementations was raised
with https://issues.apache.org/jira/browse/ARROW-10939. From the issue:
From investigation the java client requires the protobuf tags to be
sent in the message even though it is empty. Java code can be seen here:
https://github.com/apache/arrow/blob/master/java/flight/flight-core/src/main/java/org/apache/arrow/flight/ArrowMessage.java
Line 257-301 (the error is that it wont accept a null body for a record
batch)
Normal functionality of gRPC is to exclude the entire tag if an object
is empty, example code from generated csharp:
if (DataBody.Length != 0)
{ output.WriteRawTag(194, 62); output.WriteBytes(DataBody); }
The .NET code is generated by the gRPC generator
(https://github.com/grpc/grpc/tree/master/src/csharp/Grpc.Tools), so it applies
to all .NET gRPC code, not just Arrow Flight.
Does anyone have any thoughts/opinions on whether this should be fixed in the
Java code or the .NET code? Which way aligns with the spec?
Thanks
Eric Erhardt
