IsConnectionError tells whether this error should reconnect to Database.

IsUnretryableConnectionError checks whether it's an unretryable connection error or not.

LinearIncrease represents increase time wait retry policy, every retry should wait more time depends on increasing retry times.

Stable represents fixed time wait retry policy, every retry should wait a fixed time.

ParseRelayLogErrMsgs list the error messages of some un-recoverable relay log parsing error, which is used in task auto recovery.

ReplicationErrMsgs list the error message of un-recoverable replication error.

UnresumableErrCodes is a set of unresumeable err codes.

UnresumableRelayErrCodes is a set of unresumeable relay unit err codes.

UnsupportedDDLMsgs list the error messages of some unsupported DDL in TiDB.

UnsupportedDMLMsgs list the error messages of some un-recoverable DML, which is used in task auto recovery.

FiniteRetryer wraps params.

FiniteRetryStrategy will retry `RetryCount` times when failed to operate DB.

Params define parameters for Apply it's a parameters union set of all implements which implement Apply.

Retryer retries operateFn until success or reaches retry limit todo: merge with Strategy when refactor.

Strategy define different kind of retry strategy.

OperateFunc the function we can retry return: (result of operation, error of operation).