Hi Marina, We hit a similar problem with our S3 connectors. We added a level of indirection, a JSON validating microservice, before publishing to the Kafka topic. The microservice published non-JSON formatted messages to a separate Kafka topic called error-jsons and we flushed those messages using a custom consumer which handles all messages as binaries. Hope that helps.
Thanks, Dhawan On Wed, Oct 18, 2017 at 10:39 AM, Marina Popova <ppin...@protonmail.com> wrote: > Hi, > I wanted to give this question a second try.... as I feel it is very > important to understand how to control error cases with Connectors. > Any advice on how to control handling of "poison" messages in case of > connectors? > > Thanks! > Marina > > > Hi, > > I have the FileStreamSinkConnector working perfectly fine in a > distributed mode when only good messages are being sent to the input event > topic. > > > > However, if I send a message that is bad - for example, not in a correct > JSON format, and I am using the Json converter for keys/values as following: > > key.converter=org.apache.kafka.connect.json.JsonConverter > > value.converter=org.apache.kafka.connect.json.JsonConverter > > > > then the Task that handles this message fails (which is expected) and > gets into the FAILED status. (and if I have more than one task, they all > eventually get killed since they all are getting this bad message to > reprocess once the rebalance happens....) > > > > So, I tried to restart the failed task as following: > > curl -X POST localhost:8083/connectors/local-file-sink/tasks/0/restart > > and it does restart , but it immediately gets the same bad message and > kills itself again..... > > > > Looks like the offset for the bad message never gets committed and Kafka > consumer (the task) keeps reading it and killing itself forever.... > > > > Is there a way to start the Task from the LATEST offset, or somehow > instruct the FileStreamSinkConnector to skip bad messages? > > > > I found this older post that describes exactly my situation: > > https://groups.google.com/forum/#!topic/confluent-platform/hkyDslGym9g > > - and the suggestion was to add handling of these errors into the > Connector code..... however, I am using the pre-packaged file sink > connector and would rather not modify its code.... > > > > Thanks!! > > Marina > > > > Sent with [ProtonMail](https://protonmail.com) Secure Email. >
