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Motivation

Currently, IQ throws InvalidStateStoreException for any types of error, that means a user cannot handle different types of error.

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The main change is to introduce new exceptions that extend from InvalidStateStoreException. InvalidStateStoreException is not thrown at all anymore, but only new sub-classes.

# Throw to user exception
public class StateStoreMigratedException extends InvalidStateStoreException
public class StateStoreRetryableException extends InvalidStateStoreException
public class StateStoreFailException extends InvalidStateStoreException

 
# Internal exception
public class StateStoreClosedException extends InvalidStateStoreException
public class StateStoreEmptyException extends InvalidStateStoreException
public class StreamThreadNotRunningException extends InvalidStateStoreException

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Three categories exception throw to the user:

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During user call one of above methods, we should check KafkaStreams state by the following rule when InvalidStateStoreException is thrown:

• If state is RUNNING or REBALANCING:
  • StateStoreClosedException: should be wrapped to StateStoreRetryableException
  • StreamThreadNotRunningException: should be wrapped to StateStoreRetryableException
  • StateStoreEmptyException: should be wrapped to StateStoreMigratedException
• if state is PENDING_SHUTDOWN or ERROR or NOT_RUNNING:
  • wrap InvalidStateStoreException(include sub classes) to StateStoreFailException

Call Trace

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