protected List<SourceRecord> poll() throws InterruptedException {
        try {
            return task.poll();
        } catch (RetriableException | org.apache.kafka.common.errors.RetriableException e) {
            log.warn("{} failed to poll records from SourceTask. Will retry operation.", this, e);
            // Do nothing. Let the framework poll whenever it's ready.
            return null;
        }
    }
Try to send a batch of records. If a send fails and is retriable, this saves the remainder of the batch so it can
be retried after backing off. If a send fails and is not retriable, this will throw a ConnectException.
@return true if all messages were sent, false if some need to be retried
connect/runtime/src/main/java/org/apache/kafka/connect/runtime/AbstractWorkerSourceTask.java