Sanitize readings from database history topic

2017-08-24 20:48:39,129] ERROR Failed to start the connector (see other exception), but got this error while cleaning up (io.debezium.connector.mysql.MySqlConnectorTask:183)
java.lang.NullPointerException
at io.debezium.connector.mysql.MySqlConnectorTask.stop(MySqlConnectorTask.java:220)
at io.debezium.connector.mysql.MySqlConnectorTask.start(MySqlConnectorTask.java:180)
at org.apache.kafka.connect.runtime.WorkerSourceTask.execute(WorkerSourceTask.java:137)
at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:140)
at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:175)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
[2017-08-24 20:48:39,140] ERROR Task mysql-connector-0 threw an uncaught and unrecoverable exception (org.apache.kafka.connect.runtime.WorkerTask:142)
org.apache.kafka.connect.errors.ConnectException: java.lang.NullPointerException
at io.debezium.connector.mysql.MySqlConnectorTask.start(MySqlConnectorTask.java:192)
at org.apache.kafka.connect.runtime.WorkerSourceTask.execute(WorkerSourceTask.java:137)
at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:140)
at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:175)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
at io.debezium.relational.history.HistoryRecordComparator.isSameSource(HistoryRecordComparator.java:60)
at io.debezium.relational.history.HistoryRecordComparator.isAtOrBefore(HistoryRecordComparator.java:52)
at io.debezium.relational.history.AbstractDatabaseHistory.lambda$recover$0(AbstractDatabaseHistory.java:53)
at io.debezium.relational.history.AbstractDatabaseHistory$$Lambda$104/1659651213.accept(Unknown Source)
at io.debezium.relational.history.KafkaDatabaseHistory.recoverRecords(KafkaDatabaseHistory.java:202)
at io.debezium.relational.history.AbstractDatabaseHistory.recover(AbstractDatabaseHistory.java:52)
at io.debezium.connector.mysql.MySqlSchema.loadHistory(MySqlSchema.java:312)
at io.debezium.connector.mysql.MySqlTaskContext.loadHistory(MySqlTaskContext.java:116)
at io.debezium.connector.mysql.MySqlConnectorTask.start(MySqlConnectorTask.java:80)
... 8 more
[2017-08-24 20:48:39,142] ERROR Task is being killed and will not recover until manually restarted (org.apache.kafka.connect.runtime.WorkerTask:143)