Can't insert blob as map value

[nivekuil]

For some reason a byte array can't be serialized if it's in a map. I added a failing test to show this nivekuil@3b49737 which throws an exception Caused by: com.datastax.oss.driver.api.core.type.codec.CodecNotFoundException: Codec not found for requested operation: [BLOB <-> [B]

[nivekuil]

same for vector/List, looking into it I found some leads:

apache/cassandra-java-driver#1555
apache/cassandra-spark-connector#1334

[nivekuil]

From the first link, I figured out a workaround

If you are looking for a BLOB codec, the right call is CachingCodecRegistry.codecFor(DataType.BLOB, ByteBuffer.class). Indeed, there is a default BLOB codec registered in the driver that converts BLOB columns to ByteBuffer objects.

But, as explained in the docs, this method does not accept covariant classes. So if you try, say, CachingCodecRegistry.codecFor(DataType.BLOB, HeapByteBuffer.class) – then the method will throw CodecNotFoundException – even if HeapByteBuffer is a subtype of ByteBuffer.

This is probably not the right way to fix it, but this unblocks me for now df69e50