[fix][txn] Fix append txn message is lower than lowWaterMark decrease PendingWriteOps

[congbobo184]

Motivation

when send txn message is lower than low watermark, tb will throwNotAllowedException, but now we don't decrease PendingWriteOps, if PendingWriteOps != 0 and managed ledger in WriteFailed state, we can't roll over the ledger and create a new ledger.

pulsar/pulsar-broker/src/main/java/org/apache/pulsar/broker/service/persistent/PersistentTopic.java

Lines 492 to 507 in 336fcb0

	private void decrementPendingWriteOpsAndCheck() {
	long pending = pendingWriteOps.decrementAndGet();
	if (pending == 0 && isFenced && !isClosingOrDeleting) {
	synchronized (this) {
	if (isFenced && !isClosingOrDeleting) {
	messageDeduplication.resetHighestSequenceIdPushed();
	log.info("[{}] Un-fencing topic...", topic);
	// signal to managed ledger that we are ready to resume by creating a new ledger
	ledger.readyToCreateNewLedger();
	unfence();
	}
	}
	}
	}

Modifications

when tb throw NotAllowedException, we should do decrementPendingWriteOpsAndCheck

Verifying this change

add the check for pendingWriteOps

Does this pull request potentially affect one of the following parts:

If yes was chosen, please highlight the changes

• Dependencies (does it add or upgrade a dependency): (no)
• The public API: (no)
• The schema: (no)
• The default values of configurations: (no)
• The wire protocol: (no)
• The rest endpoints: (no)
• The admin cli options: (no)
• Anything that affects deployment: (no)

Documentation

• Does this pull request introduces a new feature? (yes)

• If yes, how is the feature documented? (not applicable / docs / JavaDocs / not documented)

• If a feature is not applicable for documentation, explain why?

• If a feature is not documented yet in this PR, please create a follow-up issue for adding the documentation

• doc-not-needed

[nicoloboschi]

Good catch!