[GitHub] [kafka] C0urante commented on a diff in pull request #14005: KAFKA-15177: Implement KIP-875 SourceConnector::alterOffset API in MirrorMaker 2 connectors
C0urante commented on code in PR #14005:
URL: https://github.com/apache/kafka/pull/14005#discussion_r1269901272
##
connect/runtime/src/test/java/org/apache/kafka/connect/util/clusters/EmbeddedKafkaCluster.java:
##
@@ -597,7 +596,9 @@ private Set listPartitions(
Admin admin,
Collection topics
) throws TimeoutException, InterruptedException, ExecutionException {
-assertFalse("collection of topics may not be empty", topics.isEmpty());
Review Comment:
Did the same in `assertConnectorAndExactlyNumTasksAreRunning`.
##
connect/mirror/src/main/java/org/apache/kafka/connect/mirror/MirrorUtils.java:
##
@@ -65,27 +72,170 @@ static String encodeTopicPartition(TopicPartition
topicPartition) {
static Map wrapPartition(TopicPartition topicPartition,
String sourceClusterAlias) {
Map wrapped = new HashMap<>();
-wrapped.put("topic", topicPartition.topic());
-wrapped.put("partition", topicPartition.partition());
-wrapped.put("cluster", sourceClusterAlias);
+wrapped.put(TOPIC_KEY, topicPartition.topic());
+wrapped.put(PARTITION_KEY, topicPartition.partition());
+wrapped.put(SOURCE_CLUSTER_KEY, sourceClusterAlias);
return wrapped;
}
-static Map wrapOffset(long offset) {
-return Collections.singletonMap("offset", offset);
+public static Map wrapOffset(long offset) {
+return Collections.singletonMap(OFFSET_KEY, offset);
}
-static TopicPartition unwrapPartition(Map wrapped) {
-String topic = (String) wrapped.get("topic");
-int partition = (Integer) wrapped.get("partition");
+public static TopicPartition unwrapPartition(Map wrapped) {
+String topic = (String) wrapped.get(TOPIC_KEY);
+int partition = (Integer) wrapped.get(PARTITION_KEY);
return new TopicPartition(topic, partition);
}
static Long unwrapOffset(Map wrapped) {
-if (wrapped == null || wrapped.get("offset") == null) {
+if (wrapped == null || wrapped.get(OFFSET_KEY) == null) {
return -1L;
}
-return (Long) wrapped.get("offset");
+return (Long) wrapped.get(OFFSET_KEY);
+}
+
+
+/**
+ * Validate a specific key in a source partition that may be written to
the offsets topic for one of the MM2 connectors.
+ * This method ensures that the key is present in the source partition map
and that its value is a string.
+ *
+ * @see org.apache.kafka.connect.source.SourceConnector#alterOffsets(Map,
Map)
+ * @see SourceRecord#sourcePartition()
+ *
+ * @param sourcePartition the to-be-validated source partition; may not be
null
+ * @param key the key to check for in the source partition; may be null
+ *
+ * @throws ConnectException if the offset is invalid
+ */
+static void validateSourcePartitionString(Map sourcePartition,
String key) {
+Objects.requireNonNull(sourcePartition, "Source partition may not be
null");
+
+if (!sourcePartition.containsKey(key))
+throw new ConnectException(String.format(
+"Source partition %s is missing the '%s' key, which is
required",
+sourcePartition,
+key
+));
+
+Object value = sourcePartition.get(key);
+if (!(value instanceof String)) {
+throw new ConnectException(String.format(
+"Source partition %s has an invalid value %s for the '%s'
key, which must be a string",
+sourcePartition,
+value,
+key
+));
+}
+}
+
+/**
+ * Validate the {@link #PARTITION_KEY partition key} in a source partition
that may be written to the offsets topic
+ * for one of the MM2 connectors.
+ * This method ensures that the key is present in the source partition map
and that its value is a non-negative integer.
+ *
+ * Note that the partition key most likely refers to a partition in a
Kafka topic, whereas the term "source partition" refers
+ * to a {@link SourceRecord#sourcePartition() source partition} that is
stored in a Kafka Connect worker's internal offsets
+ * topic (or, if running in standalone mode, offsets file).
+ *
+ * @see org.apache.kafka.connect.source.SourceConnector#alterOffsets(Map,
Map)
+ * @see SourceRecord#sourcePartition()
+ *
+ * @param sourcePartition the to-be-validated source partition; may not be
null
+ *
+ * @throws ConnectException if the offset is invalid
+ */
+static void validateSourcePartitionPartition(Map
sourcePartition) {
+Objects.requireNonNull(sourcePartition, "Source partition may not be
null");
+
+if (!sourcePartition.containsKey(PARTITION_KEY))
+throw new ConnectException(String.format(
+"Source partition %s is missing the '%s'
[GitHub] [kafka] C0urante commented on a diff in pull request #14005: KAFKA-15177: Implement KIP-875 SourceConnector::alterOffset API in MirrorMaker 2 connectors
C0urante commented on code in PR #14005:
URL: https://github.com/apache/kafka/pull/14005#discussion_r1266848313
##
connect/mirror/src/test/java/org/apache/kafka/connect/mirror/integration/MirrorConnectorsIntegrationExactlyOnceTest.java:
##
@@ -46,4 +51,49 @@ public void startClusters() throws Exception {
super.startClusters();
}
+@Override
+@Test
+public void testReplication() throws Exception {
+super.testReplication();
+
+// Augment the base replication test case with some extra testing of
the offset management
+// API introduced in KIP-875
+// We do this only when exactly-once support is enabled in order to
avoid having to worry about
+// zombie tasks producing duplicate records and/or writing stale
offsets to the offsets topic
+
+String backupTopic1 = remoteTopicName("test-topic-1",
PRIMARY_CLUSTER_ALIAS);
+String backupTopic2 = remoteTopicName("test-topic-2",
PRIMARY_CLUSTER_ALIAS);
+
+// Explicitly move back to offset 0
+// Note that the connector treats the offset as the last-consumed
offset,
+// so it will start reading the topic partition from offset 1 when it
resumes
+alterMirrorMakerSourceConnectorOffsets(backup, n -> 0L,
"test-topic-1");
+// Reset the offsets for test-topic-2
+resetSomeMirrorMakerSourceConnectorOffsets(backup, "test-topic-2");
+resumeMirrorMakerConnectors(backup, MirrorSourceConnector.class);
+
+int expectedRecordsTopic1 = NUM_RECORDS_PRODUCED +
((NUM_RECORDS_PER_PARTITION - 1) * NUM_PARTITIONS);
+assertEquals(expectedRecordsTopic1,
backup.kafka().consume(expectedRecordsTopic1, RECORD_TRANSFER_DURATION_MS,
backupTopic1).count(),
+"Records were not re-replicated to backup cluster after
altering offsets.");
+int expectedRecordsTopic2 = NUM_RECORDS_PER_PARTITION * 2;
+assertEquals(expectedRecordsTopic2,
backup.kafka().consume(expectedRecordsTopic2, RECORD_TRANSFER_DURATION_MS,
backupTopic2).count(),
+"New topic was not re-replicated to backup cluster after
altering offsets.");
+
+@SuppressWarnings({"unchecked", "rawtypes"})
+Class[] connectorsToReset =
CONNECTOR_LIST.toArray(new Class[0]);
+// Resetting the offsets for the heartbeat and checkpoint connectors
doesn't have any effect
+// on their behavior, but users may want to wipe offsets from them to
prevent the offsets topic
+// from growing infinitely. So, we include them in the list of
connectors to reset as a sanity check
Review Comment:
Thanks Yash. I've pushed a change that allows arbitrary source partitions
to be used with null source offsets; LMKWYT.
I'll leave this conversation unresolved in case the next reviewer wants to
weigh in; your points are definitely worth considering!
##
connect/mirror/src/test/java/org/apache/kafka/connect/mirror/integration/MirrorConnectorsIntegrationExactlyOnceTest.java:
##
@@ -46,4 +51,49 @@ public void startClusters() throws Exception {
super.startClusters();
}
+@Override
+@Test
+public void testReplication() throws Exception {
+super.testReplication();
+
+// Augment the base replication test case with some extra testing of
the offset management
+// API introduced in KIP-875
+// We do this only when exactly-once support is enabled in order to
avoid having to worry about
+// zombie tasks producing duplicate records and/or writing stale
offsets to the offsets topic
+
+String backupTopic1 = remoteTopicName("test-topic-1",
PRIMARY_CLUSTER_ALIAS);
+String backupTopic2 = remoteTopicName("test-topic-2",
PRIMARY_CLUSTER_ALIAS);
+
+// Explicitly move back to offset 0
+// Note that the connector treats the offset as the last-consumed
offset,
+// so it will start reading the topic partition from offset 1 when it
resumes
+alterMirrorMakerSourceConnectorOffsets(backup, n -> 0L,
"test-topic-1");
+// Reset the offsets for test-topic-2
+resetSomeMirrorMakerSourceConnectorOffsets(backup, "test-topic-2");
+resumeMirrorMakerConnectors(backup, MirrorSourceConnector.class);
+
+int expectedRecordsTopic1 = NUM_RECORDS_PRODUCED +
((NUM_RECORDS_PER_PARTITION - 1) * NUM_PARTITIONS);
+assertEquals(expectedRecordsTopic1,
backup.kafka().consume(expectedRecordsTopic1, RECORD_TRANSFER_DURATION_MS,
backupTopic1).count(),
+"Records were not re-replicated to backup cluster after
altering offsets.");
+int expectedRecordsTopic2 = NUM_RECORDS_PER_PARTITION * 2;
+assertEquals(expectedRecordsTopic2,
backup.kafka().consume(expectedRecordsTopic2, RECORD_TRANSFER_DURATION_MS,
backupTopic2).count(),
+"New topic was not re-replicated to backup cluster after
altering offsets.");
+
+
[GitHub] [kafka] C0urante commented on a diff in pull request #14005: KAFKA-15177: Implement KIP-875 SourceConnector::alterOffset API in MirrorMaker 2 connectors
C0urante commented on code in PR #14005:
URL: https://github.com/apache/kafka/pull/14005#discussion_r1265649203
##
connect/mirror/src/test/java/org/apache/kafka/connect/mirror/integration/MirrorConnectorsIntegrationExactlyOnceTest.java:
##
@@ -46,4 +51,49 @@ public void startClusters() throws Exception {
super.startClusters();
}
+@Override
+@Test
+public void testReplication() throws Exception {
+super.testReplication();
+
+// Augment the base replication test case with some extra testing of
the offset management
+// API introduced in KIP-875
+// We do this only when exactly-once support is enabled in order to
avoid having to worry about
+// zombie tasks producing duplicate records and/or writing stale
offsets to the offsets topic
+
+String backupTopic1 = remoteTopicName("test-topic-1",
PRIMARY_CLUSTER_ALIAS);
+String backupTopic2 = remoteTopicName("test-topic-2",
PRIMARY_CLUSTER_ALIAS);
+
+// Explicitly move back to offset 0
+// Note that the connector treats the offset as the last-consumed
offset,
+// so it will start reading the topic partition from offset 1 when it
resumes
+alterMirrorMakerSourceConnectorOffsets(backup, n -> 0L,
"test-topic-1");
+// Reset the offsets for test-topic-2
+resetSomeMirrorMakerSourceConnectorOffsets(backup, "test-topic-2");
+resumeMirrorMakerConnectors(backup, MirrorSourceConnector.class);
+
+int expectedRecordsTopic1 = NUM_RECORDS_PRODUCED +
((NUM_RECORDS_PER_PARTITION - 1) * NUM_PARTITIONS);
+assertEquals(expectedRecordsTopic1,
backup.kafka().consume(expectedRecordsTopic1, RECORD_TRANSFER_DURATION_MS,
backupTopic1).count(),
+"Records were not re-replicated to backup cluster after
altering offsets.");
+int expectedRecordsTopic2 = NUM_RECORDS_PER_PARTITION * 2;
+assertEquals(expectedRecordsTopic2,
backup.kafka().consume(expectedRecordsTopic2, RECORD_TRANSFER_DURATION_MS,
backupTopic2).count(),
+"New topic was not re-replicated to backup cluster after
altering offsets.");
+
+@SuppressWarnings({"unchecked", "rawtypes"})
+Class[] connectorsToReset =
CONNECTOR_LIST.toArray(new Class[0]);
+// Resetting the offsets for the heartbeat and checkpoint connectors
doesn't have any effect
+// on their behavior, but users may want to wipe offsets from them to
prevent the offsets topic
+// from growing infinitely. So, we include them in the list of
connectors to reset as a sanity check
Review Comment:
> Since the set of source partitions is limited here, shouldn't log
compaction be good enough?
It's hard to define "limited" in this sense, but if you've configured MM2 to
replicate every non-internal topic from a large cluster, then you could easily
end up with hundreds of thousands of unique source offsets. And then, if some
topics are deleted from the source cluster and other topics are created, we
could go beyond even that. I think it'd be nice to allow people to do some
cleanup in cases like that.
> If these offsets are never read back and actually used, why would users
want to "undo" partial or complete resets?
I tried to touch on this with my earlier point:
> This is especially relevant since, although the offsets topic isn't public
API, its contents are now public API (via the `GET /connectors/{name}/offsets
endpoint`), and users may want to track the offsets for these connectors for
monitoring purposes
TL;DR: The contents of the offsets topic may become an additional point of
observability for the connectors for people to discover, e.g., the total set of
replicated topic partitions or consumer groups.
> Overall, I think I'm more in favor of only allowing standard use cases
with the offsets management REST APIs to reduce the potential number of
footguns for users.
I definitely agree with the general mentality here of reducing the API
surface in order to minimize the potential for users to hurt themselves. But is
there any actual risk in the specific case of publishing tombstones for
arbitrary topic partitions?
In general I'd still like it if we could provide a fairly flexible API for
these connectors, but if that's too risky, one alternative could be to only
permit tombstones with validated source partitions. This would still allow for
cleanup (with no distinction between total and partial resets), but wouldn't
support an "undo" for total/partial resets, or removal of garbage source
partitions.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: jira-unsubscr...@kafka.apache.org
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org
[GitHub] [kafka] C0urante commented on a diff in pull request #14005: KAFKA-15177: Implement KIP-875 SourceConnector::alterOffset API in MirrorMaker 2 connectors
C0urante commented on code in PR #14005:
URL: https://github.com/apache/kafka/pull/14005#discussion_r1262913499
##
connect/mirror/src/test/java/org/apache/kafka/connect/mirror/integration/MirrorConnectorsIntegrationExactlyOnceTest.java:
##
@@ -46,4 +51,49 @@ public void startClusters() throws Exception {
super.startClusters();
}
+@Override
+@Test
+public void testReplication() throws Exception {
+super.testReplication();
+
+// Augment the base replication test case with some extra testing of
the offset management
+// API introduced in KIP-875
+// We do this only when exactly-once support is enabled in order to
avoid having to worry about
+// zombie tasks producing duplicate records and/or writing stale
offsets to the offsets topic
+
+String backupTopic1 = remoteTopicName("test-topic-1",
PRIMARY_CLUSTER_ALIAS);
+String backupTopic2 = remoteTopicName("test-topic-2",
PRIMARY_CLUSTER_ALIAS);
+
+// Explicitly move back to offset 0
+// Note that the connector treats the offset as the last-consumed
offset,
+// so it will start reading the topic partition from offset 1 when it
resumes
+alterMirrorMakerSourceConnectorOffsets(backup, n -> 0L,
"test-topic-1");
+// Reset the offsets for test-topic-2
+resetSomeMirrorMakerSourceConnectorOffsets(backup, "test-topic-2");
+resumeMirrorMakerConnectors(backup, MirrorSourceConnector.class);
+
+int expectedRecordsTopic1 = NUM_RECORDS_PRODUCED +
((NUM_RECORDS_PER_PARTITION - 1) * NUM_PARTITIONS);
+assertEquals(expectedRecordsTopic1,
backup.kafka().consume(expectedRecordsTopic1, RECORD_TRANSFER_DURATION_MS,
backupTopic1).count(),
+"Records were not re-replicated to backup cluster after
altering offsets.");
+int expectedRecordsTopic2 = NUM_RECORDS_PER_PARTITION * 2;
+assertEquals(expectedRecordsTopic2,
backup.kafka().consume(expectedRecordsTopic2, RECORD_TRANSFER_DURATION_MS,
backupTopic2).count(),
+"New topic was not re-replicated to backup cluster after
altering offsets.");
+
+@SuppressWarnings({"unchecked", "rawtypes"})
+Class[] connectorsToReset =
CONNECTOR_LIST.toArray(new Class[0]);
+// Resetting the offsets for the heartbeat and checkpoint connectors
doesn't have any effect
+// on their behavior, but users may want to wipe offsets from them to
prevent the offsets topic
+// from growing infinitely. So, we include them in the list of
connectors to reset as a sanity check
Review Comment:
Heh, I was wondering if we'd have to do a deep dive on the rationale here.
There are a few thoughts I had about what kind of offset tweaking to allow
for the checkpoint and heartbeat connectors:
- (As noted in the comment here) Users may want to tombstone offsets for
these connectors to prevent the offsets topic from growing infinitely
- We have no way of knowing if the set of offsets given to us is the total
set or not, so we can't choose to only allow total resets instead of partial
resets
- Since partial resets become possible, it seems reasonable to allow users
to "undo" a partial reset by re-submitting an offset for a given partition
- This is especially relevant since, although the offsets topic isn't public
API, its contents are now public API (via the `GET /connectors/{name}/offsets`
endpoint), and users may want to track the offsets for these connectors for
monitoring purposes
- We may make use of these offsets in future versions of these connectors,
at which point, it'll be nice to know that the only offsets that we can ever
encounter are the ones that were either emitted by the connector, or at least
match the format of ones emitted by the connector
Also, I think the `UnsupportedOperationException` case was more intended for
when offsets are managed externally, not for when it doesn't seem to make sense
to modify them (because, e.g., they're never read back by the connector or its
tasks).
So with all this in mind, I figured it'd be best to allow offsets to be
modified by users, but only if they match the format of the offsets that the
connector's tasks already emit. Thoughts?
As an aside... I'm wondering if we should abandon all kinds of validation
when the proposed partition/offset pair is a tombstone. Just in case the
offsets topic somehow ends up with garbage in it, it'd be nice to allow users
to clean it up via the REST API, and if there's no existing partition/offset
pair in the offsets topic for the given partition already, then emitting a
tombstone effectively becomes a no-op. Thoughts x2?
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: jira-unsubscr...@kafka.apache.org
For queries
[GitHub] [kafka] C0urante commented on a diff in pull request #14005: KAFKA-15177: Implement KIP-875 SourceConnector::alterOffset API in MirrorMaker 2 connectors
C0urante commented on code in PR #14005:
URL: https://github.com/apache/kafka/pull/14005#discussion_r1261630589
##
connect/runtime/src/test/java/org/apache/kafka/connect/util/clusters/EmbeddedKafkaCluster.java:
##
@@ -597,7 +596,9 @@ private Set listPartitions(
Admin admin,
Collection topics
) throws TimeoutException, InterruptedException, ExecutionException {
-assertFalse("collection of topics may not be empty", topics.isEmpty());
Review Comment:
Removed assertions from this API as it added an implicit dependency on JUnit
4, which we don't use in the `:connect:mirror` module.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: jira-unsubscr...@kafka.apache.org
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org
