[FLINK-7997] Avro should be always in the user code

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.4.0
• Assignee: Stephan Ewen
• Reporter: Stephan Ewen
• Created: 06/Nov/17 13:40
• Updated: 07/Nov/17 13:30
• Resolved: 06/Nov/17 19:00

Description

Having Avro in the user code space makes it possible for users to use different Avro versions that the ones pulled in by an overloaded classpath (for example when having Hadoop in the classpath)

This is possible through the new child-first classloading in Flink 1.4.

Also, this should fix the problem of "X cannot be cast to X", because Avro classes will be scoped to the user code class loader, and the Avro schema cache will not be JVM-wide-