[KAFKA-12170] Connect Cast cannot deal with fields of type "bytes" correctly

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.7.0, 2.6.1
• Fix Version/s: 3.0.0
• Component/s: KafkaConnect
• Labels: pull-request-available
• Flags: Patch, Important
• Assignee: Sven Erik Knop
• Reporter: Sven Erik Knop
• Created: 10/Jan/21 11:02
• Updated: 03/Mar/21 22:18
• Resolved: 03/Mar/21 22:18

Description

Cast operation on a field of type bytes to a string returns the default ByteBuffer representation, not the content. For example, a field called "payload" of type bytes transformed in this way:

payload:string

Returns the result 

"payload":{"string":"java.nio.HeapByteBuffer[pos=0 lim=4 cap=4]"}

We propose instead to represent the byte array as a hex string

"payload":{"string":"FFEEDDAABB123F"}

Issue Links

• relates to: KAFKA-6684 Support casting values with bytes schema to string
• links to: GitHub Pull Request #9950