Thanks all, this is a large KIP and has sparked a lot of great discussion, both on and off the dev list. I'm closing the vote with the following results:
+12 non-binding +3 binding The KIP is accepted! Thanks, Ryanne On Fri, Jan 11, 2019 at 9:48 PM Becket Qin <becket....@gmail.com> wrote: > > Hi Ryanne, > > Thanks for the KIP and patient discussion. +1 from me as well. > > Jiangjie (Becket) Qin > > On Fri, Jan 11, 2019 at 1:11 AM Jun Rao <j...@confluent.io> wrote: >> >> Hi, Ryanne, >> >> Thanks for the explanation. All make sense to me now. +1 on the KIP from me. >> >> Jun >> >> On Wed, Jan 9, 2019 at 7:16 PM Ryanne Dolan <ryannedo...@gmail.com> wrote: >> >> > Thanks Jun. >> > >> > > 103. My point was that the MirrorMakerConnector can die while the >> > Heartbeat connector is still alive. So, one can't solely rely on Heartbeat >> > for monitoring? >> > >> > Each cluster will have a heartbeat topic produced by >> > MirrorHeartbeatConnector, which doesn't have an associated "source" other >> > than time. This topic gets picked up by downstream MirrorSourceConnectors >> > and replicated like A.heartbeat. So the heartbeat topic itself isn't >> > particular useful for monitoring, but the downstream A.heartbeat shows that >> > heartbeats are being replicated successfully from A -> B. If a >> > MirrorSourceConnector fails while replicating A -> B, you'd still see >> > heartbeats in cluster B, but not A.heartbeat. >> > >> > 105. You're correct, you don't need to know "B" in order to go from A's >> > topic1 to B's A.topic1, i.e. migrating downstream. But you need to know "B" >> > to go from A's B.topic1 to B's topic1. In the latter case, you are >> > consuming a remote topic to begin with, and then migrating to the source >> > cluster, i.e. migrating upstream. N.B. you strip the "B" prefix in this >> > case, rather than add the "A" prefix. And you can't just strip all >> > prefixes, because you could be migrating from e.g. A's C.topic1 to B's >> > C.topic1, i.e. migrating "laterally", if you will. >> > >> > I suppose we could break this out into multiple methods (upstream, >> > downstream, lateral etc), but I think that would add a lot more complexity >> > and confusion to the API. By providing both A and B, the single method can >> > always figure out what to do. >> > >> > 107. done >> > >> > Thanks, >> > Ryanne >> > >> > >> > >> > >> > On Wed, Jan 9, 2019 at 6:11 PM Jun Rao <j...@confluent.io> wrote: >> > >> >> Hi, Ryanne, >> >> >> >> 103. My point was that the MirrorMakerConnector can die while the >> >> Heartbeat connector is still alive. So, one can't solely rely on Heartbeat >> >> for monitoring? >> >> >> >> 105. Hmm, maybe I don't understand how this is done. Let's say we replica >> >> topic1 from cluster A to cluster B. My understanding is that to translate >> >> the offset from A to B for a consumer group, we read A.checkpoint file in >> >> cluster B to get the timestamp of the last checkpointed offset, call >> >> consumer.offsetsForTimes() on A.topic1 in cluster B to translate the >> >> timestamp to a local offset, and return <A.topic1, translated offset>. >> >> Is that right? If so, in all steps, we don't need to know the >> >> targetClusterAlias B. We just need to know the connection string to >> >> cluster B, which targetConsumerConfig provides. >> >> >> >> 107. Thanks. Could you add that description to the KIP? >> >> >> >> Thanks, >> >> >> >> Jun >> >> >> >> On Mon, Jan 7, 2019 at 3:50 PM Ryanne Dolan <ryannedo...@gmail.com> >> >> wrote: >> >> >> >>> Thanks Jun, I've updated the KIP as requested. Brief notes below: >> >>> >> >>> 100. added "...out-of-the-box (without custom handlers)..." >> >>> >> >>> 101. done. Good idea to include a MessageFormatter. >> >>> >> >>> 102. done. >> >>> >> >>> > 103. [...] why is Heartbeat a separate connector? >> >>> >> >>> Heartbeats themselves are replicated via MirrorSource/SinkConnector, so >> >>> if replication stops, you'll stop seeing heartbeats in downstream >> >>> clusters. >> >>> I've updated the KIP to make this clearer and have added a bullet to >> >>> Rejected Alternatives. >> >>> >> >>> 104. added "heartbeat.retention.ms", "checkpoint.retention.ms", thanks. >> >>> The heartbeat topic doesn't need to be compacted. >> >>> >> >>> > 105. [...] I am not sure why targetClusterAlias is useful >> >>> >> >>> In order to map A's B.topic1 to B's topic1, we need to know B. >> >>> >> >>> > 106. [...] should the following properties be prefixed with "consumer." >> >>> >> >>> No, they are part of Connect's worker config. >> >>> >> >>> > 107. So, essentially it's running multiple logical connect clusters on >> >>> the same shared worker nodes? >> >>> >> >>> Correct. Rather than configure each Connector and Worker and Herder >> >>> individually, a single top-level configuration file is used. And instead >> >>> of >> >>> running a bunch of separate worker processes on each node, a single >> >>> process >> >>> runs multiple workers. This is implemented using a separate driver based >> >>> on >> >>> ConnectDistributed, but which runs multiple DistributedHerders. Each >> >>> DistributedHerder uses a different Kafka cluster for coordination -- they >> >>> are completely separate apart from running in the same process. >> >>> >> >>> Thanks for helping improve the doc! >> >>> Ryanne >> >>> >> >>> On Fri, Jan 4, 2019 at 10:33 AM Jun Rao <j...@confluent.io> wrote: >> >>> >> >>>> Hi, Ryanne, >> >>>> >> >>>> Thanks for KIP. Still have a few more comments below. >> >>>> >> >>>> 100. "This is not possible with MirrorMaker today -- records would be >> >>>> replicated back and forth indefinitely, and the topics in either cluster >> >>>> would be merged inconsistently between clusters. " This is not 100% true >> >>>> since MM can do the topic renaming through MirrorMakerMessageHandler. >> >>>> >> >>>> 101. For both Heartbeat and checkpoint, could you define the full >> >>>> schema, >> >>>> including the field type? Also how are they serialized into the Kafka >> >>>> topic? Is it JSON or sth else? For convenience, it would be useful to >> >>>> provide a built-in MessageFormatter so that one can read each topic's >> >>>> data >> >>>> using tools like ConsoleConsumer. >> >>>> >> >>>> 102. For the public Heartbeat and Checkpoint class, could you list the >> >>>> public methods in each class? >> >>>> >> >>>> 103. I am wondering why is Heartbeat a separate connector? A MirrorMaker >> >>>> connector can die independent of the Heartbeat connector, which seems to >> >>>> defeat the purpose of heartbeat. >> >>>> >> >>>> 104. Is the Heartbeat topic also a compacted topic? If not, how long is >> >>>> it >> >>>> retained for? >> >>>> >> >>>> 105. For the following, I am not sure why targetClusterAlias is useful? >> >>>> The >> >>>> checkpoint file seems to only include sourceClusterAlias. >> >>>> >> >>>> Map<TopicPartition, Long> translateOffsets(Map<?, ?> >> >>>> targetConsumerConfig, >> >>>> String sourceClusterAlias, String targetClusterAlias, String >> >>>> remoteGroupId) >> >>>> >> >>>> 106. In the configuration example, should the following properties be >> >>>> prefixed with "consumer."? >> >>>> key.converter >> >>>> <https://cwiki.apache.org/confluence/display/KAFKA/key.converter> = >> >>>> org.apache.kafka.connect.converters.ByteArrayConverter >> >>>> < >> >>>> https://cwiki.apache.org/confluence/display/KAFKA/org.apache.kafka.connect.converters.ByteArrayConverter >> >>>> > >> >>>> value.converter >> >>>> <https://cwiki.apache.org/confluence/display/KAFKA/value.converter> = >> >>>> org.apache.kafka.connect.converters.ByteArrayConverter >> >>>> < >> >>>> https://cwiki.apache.org/confluence/display/KAFKA/org.apache.kafka.connect.converters.ByteArrayConverter >> >>>> > >> >>>> >> >>>> 107. Could you add a bit more description on how >> >>>> connect-mirror-maker.sh is >> >>>> implemented? My understanding is that it will start as many as >> >>>> separate DistributedHerder as the Kafka clusters? So, essentially it's >> >>>> running multiple logical connect clusters on the same shared worker >> >>>> nodes? >> >>>> >> >>>> Thanks, >> >>>> >> >>>> Jun >> >>>> >> >>>> >> >>>> On Thu, Dec 20, 2018 at 5:23 PM Srinivas Reddy < >> >>>> srinivas96all...@gmail.com> >> >>>> wrote: >> >>>> >> >>>> > +1 (non binding) >> >>>> > >> >>>> > Thank you Ryan for the KIP, let me know if you need support in >> >>>> implementing >> >>>> > it. >> >>>> > >> >>>> > - >> >>>> > Srinivas >> >>>> > >> >>>> > - Typed on tiny keys. pls ignore typos.{mobile app} >> >>>> > >> >>>> > >> >>>> > On Fri, 21 Dec, 2018, 08:26 Ryanne Dolan <ryannedo...@gmail.com >> >>>> wrote: >> >>>> > >> >>>> > > Thanks for the votes so far! >> >>>> > > >> >>>> > > Due to recent discussions, I've removed the high-level REST API >> >>>> from the >> >>>> > > KIP. >> >>>> > > >> >>>> > > On Thu, Dec 20, 2018 at 12:42 PM Paul Davidson < >> >>>> pdavid...@salesforce.com >> >>>> > > >> >>>> > > wrote: >> >>>> > > >> >>>> > > > +1 >> >>>> > > > >> >>>> > > > Would be great to see the community build on the basic approach >> >>>> we took >> >>>> > > > with Mirus. Thanks Ryanne. >> >>>> > > > >> >>>> > > > On Thu, Dec 20, 2018 at 9:01 AM Andrew Psaltis < >> >>>> > psaltis.and...@gmail.com >> >>>> > > > >> >>>> > > > wrote: >> >>>> > > > >> >>>> > > > > +1 >> >>>> > > > > >> >>>> > > > > Really looking forward to this and to helping in any way I can. >> >>>> > Thanks >> >>>> > > > for >> >>>> > > > > kicking this off Ryanne. >> >>>> > > > > >> >>>> > > > > On Thu, Dec 20, 2018 at 10:18 PM Andrew Otto < >> >>>> o...@wikimedia.org> >> >>>> > > wrote: >> >>>> > > > > >> >>>> > > > > > +1 >> >>>> > > > > > >> >>>> > > > > > This looks like a huge project! Wikimedia would be very >> >>>> excited to >> >>>> > > have >> >>>> > > > > > this. Thanks! >> >>>> > > > > > >> >>>> > > > > > On Thu, Dec 20, 2018 at 9:52 AM Ryanne Dolan < >> >>>> > ryannedo...@gmail.com> >> >>>> > > > > > wrote: >> >>>> > > > > > >> >>>> > > > > > > Hey y'all, please vote to adopt KIP-382 by replying +1 to >> >>>> this >> >>>> > > > thread. >> >>>> > > > > > > >> >>>> > > > > > > For your reference, here are the highlights of the proposal: >> >>>> > > > > > > >> >>>> > > > > > > - Leverages the Kafka Connect framework and ecosystem. >> >>>> > > > > > > - Includes both source and sink connectors. >> >>>> > > > > > > - Includes a high-level driver that manages connectors in a >> >>>> > > dedicated >> >>>> > > > > > > cluster. >> >>>> > > > > > > - High-level REST API abstracts over connectors between >> >>>> multiple >> >>>> > > > Kafka >> >>>> > > > > > > clusters. >> >>>> > > > > > > - Detects new topics, partitions. >> >>>> > > > > > > - Automatically syncs topic configuration between clusters. >> >>>> > > > > > > - Manages downstream topic ACL. >> >>>> > > > > > > - Supports "active/active" cluster pairs, as well as any >> >>>> number >> >>>> > of >> >>>> > > > > active >> >>>> > > > > > > clusters. >> >>>> > > > > > > - Supports cross-data center replication, aggregation, and >> >>>> other >> >>>> > > > > complex >> >>>> > > > > > > topologies. >> >>>> > > > > > > - Provides new metrics including end-to-end replication >> >>>> latency >> >>>> > > > across >> >>>> > > > > > > multiple data centers/clusters. >> >>>> > > > > > > - Emits offsets required to migrate consumers between >> >>>> clusters. >> >>>> > > > > > > - Tooling for offset translation. >> >>>> > > > > > > - MirrorMaker-compatible legacy mode. >> >>>> > > > > > > >> >>>> > > > > > > Thanks, and happy holidays! >> >>>> > > > > > > Ryanne >> >>>> > > > > > > >> >>>> > > > > > >> >>>> > > > > >> >>>> > > > >> >>>> > > > >> >>>> > > > -- >> >>>> > > > Paul Davidson >> >>>> > > > Principal Engineer, Ajna Team >> >>>> > > > Big Data & Monitoring >> >>>> > > > >> >>>> > > >> >>>> > >> >>>> >> >>>
