Hi Till, You are right. It all depends on when the new source interface is going to be ready. Personally I think it would be there in about a month or so. But I could be too optimistic. It would also be good to hear what do Aljoscha and Stephan think as they are also involved in FLIP-27.
In general I think we should have Pulsar connector in Flink 1.10, preferably with the new source interface. We can also check it in right now with old source interface, but I suspect few users will use it before the next official release. Therefore, it seems reasonable to wait a little bit to see whether we can jump to the new source interface. As long as we make sure Flink 1.10 has it, waiting a little bit doesn't seem to hurt much. Thanks, Jiangjie (Becket) Qin On Thu, Sep 5, 2019 at 3:59 PM Till Rohrmann <trohrm...@apache.org> wrote: > Hi everyone, > > I'm wondering what the problem would be if we committed the Pulsar > connector before the new source interface is ready. If I understood it > correctly, then we need to support the old source interface anyway for the > existing connectors. By checking it in early I could see the benefit that > our users could start using the connector earlier. Moreover, it would > prevent that the Pulsar integration is being delayed in case that the > source interface should be delayed. The only downside I see is the extra > review effort and potential fixes which might be irrelevant for the new > source interface implementation. I guess it mainly depends on how certain > we are when the new source interface will be ready. > > Cheers, > Till > > On Thu, Sep 5, 2019 at 8:56 AM Becket Qin <becket....@gmail.com> wrote: > > > Hi Sijie and Yijie, > > > > Thanks for sharing your thoughts. > > > > Just want to have some update on FLIP-27. Although the FLIP wiki and > > discussion thread has been quiet for some time, a few committer / > > contributors in Flink community were actually prototyping the entire > thing. > > We have made some good progress there but want to update the FLIP wiki > > after the entire thing is verified to work in case there are some last > > minute surprise in the implementation. I don't have an exact ETA yet, > but I > > guess it is going to be within a month or so. > > > > I am happy to review the current Flink Pulsar connector and see if it > would > > fit in FLIP-27. It would be good to avoid the case that we checked in the > > Pulsar connector with some review efforts and shortly after that the new > > Source interface is ready. > > > > Thanks, > > > > Jiangjie (Becket) Qin > > > > On Thu, Sep 5, 2019 at 8:39 AM Yijie Shen <henry.yijies...@gmail.com> > > wrote: > > > > > Thanks for all the feedback and suggestions! > > > > > > As Sijie said, the goal of the connector has always been to provide > > > users with the latest features of both systems as soon as possible. We > > > propose to contribute the connector to Flink and hope to get more > > > suggestions and feedback from Flink experts to ensure the high quality > > > of the connector. > > > > > > For FLIP-27, we noticed its existence at the beginning of reworking > > > the connector implementation based on Flink 1.9; we also wanted to > > > build a connector that supports both batch and stream computing based > > > on it. > > > However, it has been inactive for some time, so we decided to provide > > > a connector with most of the new features, such as the new type system > > > and the new catalog API first. We will pay attention to the progress > > > of FLIP-27 continually and incorporate it with the connector as soon > > > as possible. > > > > > > Regarding the test status of the connector, we are following the other > > > connectors' test in Flink repository and aimed to provide throughout > > > tests as we could. We are also happy to hear suggestions and > > > supervision from the Flink community to improve the stability and > > > performance of the connector continuously. > > > > > > Best, > > > Yijie > > > > > > On Thu, Sep 5, 2019 at 5:59 AM Sijie Guo <guosi...@gmail.com> wrote: > > > > > > > > Thanks everyone for the comments and feedback. > > > > > > > > It seems to me that the main question here is about - "how can the > > Flink > > > > community maintain the connector?". > > > > > > > > Here are two thoughts from myself. > > > > > > > > 1) I think how and where to host this integration is kind of less > > > important > > > > here. I believe there can be many ways to achieve it. > > > > As part of the contribution, what we are looking for here is how > these > > > two > > > > communities can build the collaboration relationship on developing > > > > the integration between Pulsar and Flink. Even we can try our best to > > > catch > > > > up all the updates in Flink community. We are still > > > > facing the fact that we have less experiences in Flink than folks in > > > Flink > > > > community. In order to make sure we maintain and deliver > > > > a high-quality pulsar-flink integration to the users who use both > > > > technologies, we need some help from the experts from Flink > community. > > > > > > > > 2) We have been following FLIP-27 for a while. Originally we were > > > thinking > > > > of contributing the connectors back after integrating with the > > > > new API introduced in FLIP-27. But we decided to initiate the > > > conversation > > > > as early as possible. Because we believe there are more benefits > doing > > > > it now rather than later. As part of contribution, it can help Flink > > > > community understand more about Pulsar and the potential integration > > > points. > > > > Also we can also help Flink community verify the new connector API as > > > well > > > > as other new API (e.g. catalog API). > > > > > > > > Thanks, > > > > Sijie > > > > > > > > On Wed, Sep 4, 2019 at 5:24 AM Becket Qin <becket....@gmail.com> > > wrote: > > > > > > > > > Hi Yijie, > > > > > > > > > > Thanks for the interest in contributing the Pulsar connector. > > > > > > > > > > In general, I think having Pulsar connector with strong support is > a > > > > > valuable addition to Flink. So I am happy the shepherd this effort. > > > > > Meanwhile, I would also like to provide some context and recent > > > efforts on > > > > > the Flink connectors ecosystem. > > > > > > > > > > The current way Flink maintains its connector has hit the > scalability > > > bar. > > > > > With more and more connectors coming into Flink repo, we are > facing a > > > few > > > > > problems such as long build and testing time. To address this > > problem, > > > we > > > > > have attempted to do the following: > > > > > 1. Split out the connectors into a separate repository. This is > > > temporarily > > > > > on hold due to potential solution to shorten the build time. > > > > > 2. Encourage the connectors to stay as ecosystem project while > Flink > > > tries > > > > > to provide good support for functionality and compatibility tests. > > > Robert > > > > > has driven to create a Flink Ecosystem project website and it is > > going > > > > > through some final approval process. > > > > > > > > > > Given the above efforts, it would be great to first see if we can > > have > > > > > Pulsar connector as an ecosystem project with great support. It > would > > > be > > > > > good to hear how the Flink Pulsar connector is tested currently to > > see > > > if > > > > > we can learn something to maintain it as an ecosystem project with > > good > > > > > quality and test coverage. If the quality as an ecosystem project > is > > > hard > > > > > to guarantee, we may as well adopt it into the main repo. > > > > > > > > > > BTW, another ongoing effort is FLIP-27 where we are making changes > to > > > the > > > > > Flink source connector architecture and interface. This change will > > > likely > > > > > land in 1.10. Therefore timing wise, if we are going to have the > > Pulsar > > > > > connector in main repo, I am wondering if we should hold a little > bit > > > and > > > > > let the Pulsar connector adapt to the new interface to avoid > shortly > > > > > deprecated work? > > > > > > > > > > Thanks, > > > > > > > > > > Jiangjie (Becket) Qin > > > > > > > > > > On Wed, Sep 4, 2019 at 4:32 PM Chesnay Schepler < > ches...@apache.org> > > > > > wrote: > > > > > > > > > > > I'm quite worried that we may end up repeating history. > > > > > > > > > > > > There were already 2 attempts at contributing a pulsar connector, > > > both > > > > > > of which failed because no committer was getting involved, > despite > > > the > > > > > > contributor opening a dedicated discussion thread about the > > > contribution > > > > > > beforehand and getting several +1's from committers. > > > > > > > > > > > > We should really make sure that if we welcome/approve such a > > > > > > contribution it will actually get the attention it deserves. > > > > > > > > > > > > As such, I'm inclined to recommend maintaining the connector > > outside > > > of > > > > > > Flink. We could link to it from the documentation to give it more > > > > > exposure. > > > > > > With the upcoming page for sharing artifacts among the community > > > (what's > > > > > > the state of that anyway?), this may be a better option. > > > > > > > > > > > > On 04/09/2019 10:16, Till Rohrmann wrote: > > > > > > > Hi everyone, > > > > > > > > > > > > > > thanks a lot for starting this discussion Yijie. I think the > > Pulsar > > > > > > > connector would be a very valuable addition since Pulsar > becomes > > > more > > > > > and > > > > > > > more popular and it would further expand Flink's > > interoperability. > > > Also > > > > > > > from a project perspective it makes sense for me to place the > > > connector > > > > > > in > > > > > > > the downstream project. > > > > > > > > > > > > > > My main concern/question is how can the Flink community > maintain > > > the > > > > > > > connector? We have seen in the past that connectors are some of > > the > > > > > most > > > > > > > actively developed components because they need to be kept in > > sync > > > with > > > > > > the > > > > > > > external system and with Flink. Given that the Pulsar community > > is > > > > > > willing > > > > > > > to help with maintaining, improving and evolving the connector, > > I'm > > > > > > > optimistic that we can achieve this. Hence, +1 for contributing > > it > > > back > > > > > > to > > > > > > > Flink. > > > > > > > > > > > > > > Cheers, > > > > > > > Till > > > > > > > > > > > > > > > > > > > > > > > > > > > > On Wed, Sep 4, 2019 at 2:03 AM Sijie Guo <guosi...@gmail.com> > > > wrote: > > > > > > > > > > > > > >> Hi Yun, > > > > > > >> > > > > > > >> Since I was the main driver behind FLINK-9641 and FLINK-9168, > > let > > > me > > > > > > try to > > > > > > >> add more context on this. > > > > > > >> > > > > > > >> FLINK-9641 and FLINK-9168 was created for bringing Pulsar as > > > source > > > > > and > > > > > > >> sink for Flink. The integration was done with Flink 1.6.0. We > > > sent out > > > > > > pull > > > > > > >> requests about a year ago and we ended up maintaining those > > > connectors > > > > > > in > > > > > > >> Pulsar for Pulsar users to use Flink to process event streams > in > > > > > Pulsar. > > > > > > >> (See > https://github.com/apache/pulsar/tree/master/pulsar-flink > > ). > > > The > > > > > > Flink > > > > > > >> 1.6 integration is pretty simple and there is no schema > > > > > considerations. > > > > > > >> > > > > > > >> In the past year, we have made a lot of changes in Pulsar and > > > brought > > > > > > >> Pulsar schema as the first-class citizen in Pulsar. We also > > > integrated > > > > > > with > > > > > > >> other computing engines for processing Pulsar event streams > with > > > > > Pulsar > > > > > > >> schema. > > > > > > >> > > > > > > >> It led us to rethink how to integrate with Flink in the best > > way. > > > Then > > > > > > we > > > > > > >> reimplement the pulsar-flink connectors from the ground up > with > > > schema > > > > > > and > > > > > > >> bring table API and catalog API as the first-class citizen in > > the > > > > > > >> integration. With that being said, in the new pulsar-flink > > > > > > implementation, > > > > > > >> you can register pulsar as a flink catalog and query / process > > the > > > > > event > > > > > > >> streams using Flink SQL. > > > > > > >> > > > > > > >> This is an example about how to use Pulsar as a Flink catalog: > > > > > > >> > > > > > > >> > > > > > > > > > > > > > > > > > https://github.com/streamnative/pulsar-flink/blob/3eeddec5625fc7dddc3f8a3ec69f72e1614ca9c9/README.md#use-pulsar-catalog > > > > > > >> > > > > > > >> Yijie has also written a blog post explaining why we > > re-implement > > > the > > > > > > flink > > > > > > >> connector with Flink 1.9 and what are the changes we made in > the > > > new > > > > > > >> connector: > > > > > > >> > > > > > > >> > > > > > > > > > > > > > > > > > https://medium.com/streamnative/use-apache-pulsar-as-streaming-table-with-8-lines-of-code-39033a93947f > > > > > > >> > > > > > > >> We believe Pulsar is not just a simple data sink or source for > > > Flink. > > > > > It > > > > > > >> actually can be a fully integrated streaming data storage for > > > Flink in > > > > > > many > > > > > > >> areas (sink, source, schema/catalog and state). The > combination > > of > > > > > Flink > > > > > > >> and Pulsar can create a great streaming warehouse architecture > > for > > > > > > >> streaming-first, unified data processing. Since we are talking > > to > > > > > > >> contribute Pulsar integration to Flink here, we are also > > > dedicated to > > > > > > >> maintain, improve and evolve the integration with Flink to > help > > > the > > > > > > users > > > > > > >> who use both Flink and Pulsar. > > > > > > >> > > > > > > >> Hope this give you a bit more background about the pulsar > flink > > > > > > >> integration. Let me know what are your thoughts. > > > > > > >> > > > > > > >> Thanks, > > > > > > >> Sijie > > > > > > >> > > > > > > >> > > > > > > >> On Tue, Sep 3, 2019 at 11:54 AM Yun Tang <myas...@live.com> > > > wrote: > > > > > > >> > > > > > > >>> Hi Yijie > > > > > > >>> > > > > > > >>> I can see that Pulsar becomes more and more popular recently > > and > > > very > > > > > > >> glad > > > > > > >>> to see more people willing to contribute to Flink ecosystem. > > > > > > >>> > > > > > > >>> Before any further discussion, would you please give some > > > explanation > > > > > > of > > > > > > >>> the relationship between this thread to current existing > JIRAs > > of > > > > > > pulsar > > > > > > >>> source [1] and sink [2] connector? Will the contribution > > contains > > > > > part > > > > > > of > > > > > > >>> those PRs or totally different implementation? > > > > > > >>> > > > > > > >>> [1] https://issues.apache.org/jira/browse/FLINK-9641 > > > > > > >>> [2] https://issues.apache.org/jira/browse/FLINK-9168 > > > > > > >>> > > > > > > >>> Best > > > > > > >>> Yun Tang > > > > > > >>> ________________________________ > > > > > > >>> From: Yijie Shen <henry.yijies...@gmail.com> > > > > > > >>> Sent: Tuesday, September 3, 2019 13:57 > > > > > > >>> To: dev@flink.apache.org <dev@flink.apache.org> > > > > > > >>> Subject: [DISCUSS] Contribute Pulsar Flink connector back to > > > Flink > > > > > > >>> > > > > > > >>> Dear Flink Community! > > > > > > >>> > > > > > > >>> I would like to open the discussion of contributing Pulsar > > Flink > > > > > > >>> connector [0] back to Flink. > > > > > > >>> > > > > > > >>> ## A brief introduction to Apache Pulsar > > > > > > >>> > > > > > > >>> Apache Pulsar[1] is a multi-tenant, high-performance > > distributed > > > > > > >>> pub-sub messaging system. Pulsar includes multiple features > > such > > > as > > > > > > >>> native support for multiple clusters in a Pulsar instance, > with > > > > > > >>> seamless geo-replication of messages across clusters, very > low > > > > > publish > > > > > > >>> and end-to-end latency, seamless scalability to over a > million > > > > > topics, > > > > > > >>> and guaranteed message delivery with persistent message > storage > > > > > > >>> provided by Apache BookKeeper. Nowadays, Pulsar has been > > adopted > > > by > > > > > > >>> more and more companies[2]. > > > > > > >>> > > > > > > >>> ## The status of Pulsar Flink connector > > > > > > >>> > > > > > > >>> The Pulsar Flink connector we are planning to contribute is > > built > > > > > upon > > > > > > >>> Flink 1.9.0 and Pulsar 2.4.0. The main features are: > > > > > > >>> - Pulsar as a streaming source with exactly-once guarantee. > > > > > > >>> - Sink streaming results to Pulsar with at-least-once > > semantics. > > > (We > > > > > > >>> would update this to exactly-once as well when Pulsar gets > all > > > > > > >>> transaction features ready in its 2.5.0 version) > > > > > > >>> - Build upon Flink new Table API Type system (FLIP-37[3]), > and > > > can > > > > > > >>> automatically (de)serialize messages with the help of Pulsar > > > schema. > > > > > > >>> - Integrate with Flink new Catalog API (FLIP-30[4]), which > > > enables > > > > > the > > > > > > >>> use of Pulsar topics as tables in Table API as well as SQL > > > client. > > > > > > >>> > > > > > > >>> ## Reference > > > > > > >>> [0] https://github.com/streamnative/pulsar-flink > > > > > > >>> [1] https://pulsar.apache.org/ > > > > > > >>> [2] https://pulsar.apache.org/en/powered-by/ > > > > > > >>> [3] > > > > > > >>> > > > > > > >> > > > > > > > > > > > > > > > > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-37%3A+Rework+of+the+Table+API+Type+System > > > > > > >>> [4] > > > > > > >>> > > > > > > >> > > > > > > > > > > > > > > > > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-30%3A+Unified+Catalog+APIs > > > > > > >>> > > > > > > >>> Best, > > > > > > >>> Yijie Shen > > > > > > >>> > > > > > > > > > > > > > > > > > > > > > > >
