Github user arunmahadevan commented on a diff in the pull request:
https://github.com/apache/storm/pull/2639#discussion_r183539214
--- Diff:
external/storm-jms/src/main/java/org/apache/storm/jms/spout/JmsSpout.java ---
@@ -339,26 +339,26 @@ public void nextTuple() {
*/
@Override
public void ack(Object msgId) {
-
Message msg = this.pendingMessages.remove(msgId);
- JmsMessageID oldest = this.toCommit.first();
- if (msgId.equals(oldest)) {
- if (msg != null) {
- try {
- LOG.debug("Committing...");
- msg.acknowledge();
- LOG.debug("JMS Message acked: " + msgId);
- this.toCommit.remove(msgId);
- } catch (JMSException e) {
- LOG.warn("Error acknowldging JMS message: " + msgId,
e);
+ if (!toCommit.isEmpty()) {
+ JmsMessageID oldest = this.toCommit.first();
+ if (msgId.equals(oldest)) {
+ if (msg != null) {
+ try {
+ LOG.debug("Committing...");
+ msg.acknowledge();
--- End diff --
I am not sure acking the oldest message in JMS is correct even for
`CLIENT_ACKNOWLEDGE`. This would ack the new messages that have been consumed
in the session (and possibly emitted) even before the spout received the ACK
for the message. I guess we should keep removing the message from `toCommit`
and invoke the JMS ack when its the last message in `toCommit`. (assuming we
dont consume any other message in the meanwhile).
---
