I'm not saying pre-bundle some jars will make this problem go away, and you're right that only hides the problem for some users. But what if this solution can hide the problem for 90% users? Would't that be good enough for us to try?
Regarding to would users following instructions really be such a big problem? I'm afraid yes. Otherwise I won't answer such questions for at least a dozen times and I won't see such questions coming up from time to time. During some periods, I even saw such questions every day. Best, Kurt On Thu, Apr 16, 2020 at 11:21 PM Chesnay Schepler <ches...@apache.org> wrote: > The problem with having a distribution with "popular" stuff is that it > doesn't really *solve* a problem, it just hides it for users who fall > into these particular use-cases. > Move out of it and you once again run into exact same problems out-lined. > > This is exactly why I like the tooling approach; you have to deal with it > from the start and transitioning to a custom use-case is easier. > > Would users following instructions really be such a big problem? > I would expect that users generally know *what *they need, just not > necessarily how it is assembled correctly (where do get which jar, which > directory to put it in). > It seems like these are exactly the problem this would solve? > I just don't see how moving a jar corresponding to some feature from opt > to some directory (lib/plugins) is less error-prone than just selecting the > feature and having the tool handle the rest. > > As for re-distributions, it depends on the form that the tool would take. > It could be an application that runs locally and works against maven > central (note: not necessarily *using* maven); this should would work in > China, no? > > A web tool would of course be fancy, but I don't know how feasible this is > with the ASF infrastructure. > You wouldn't be able to mirror the distribution, so the load can't be > distributed. I doubt INFRA would like this. > > Note that third-parties could also start distributing use-case oriented > distributions, which would be perfectly fine as far as I'm concerned. > > On 16/04/2020 16:57, Kurt Young wrote: > > I'm not so sure about the web tool solution though. The concern I have for > this approach is the final generated > distribution is kind of non-deterministic. We might generate too many > different combinations when user trying to > package different types of connector, format, and even maybe hadoop > releases. As far as I can tell, most open > source projects and apache projects will only release some > pre-defined distributions, which most users are already > familiar with, thus hard to change IMO. And I also have went through in > some cases, users will try to re-distribute > the release package, because of the unstable network of apache website from > China. In web tool solution, I don't > think this kind of re-distribution would be possible anymore. > > In the meantime, I also have a concern that we will fall back into our trap > again if we try to offer this smart & flexible > solution. Because it needs users to cooperate with such mechanism. It's > exactly the situation what we currently fell > into: > 1. We offered a smart solution. > 2. We hope users will follow the correct instructions. > 3. Everything will work as expected if users followed the right > instructions. > > In reality, I suspect not all users will do the second step correctly. And > for new users who only trying to have a quick > experience with Flink, I would bet most users will do it wrong. > > So, my proposal would be one of the following 2 options: > 1. Provide a slim distribution for advanced product users and provide a > distribution which will have some popular builtin jars. > 2. Only provide a distribution which will have some popular builtin jars. > > If we are trying to reduce the distributions we released, I would prefer 2 > > 1. > > Best, > Kurt > > > On Thu, Apr 16, 2020 at 9:33 PM Till Rohrmann <trohrm...@apache.org> > <trohrm...@apache.org> wrote: > > > I think what Chesnay and Dawid proposed would be the ideal solution. > Ideally, we would also have a nice web tool for the website which generates > the corresponding distribution for download. > > To get things started we could start with only supporting to > download/creating the "fat" version with the script. The fat version would > then consist of the slim distribution and whatever we deem important for > new users to get started. > > Cheers, > Till > > On Thu, Apr 16, 2020 at 11:33 AM Dawid Wysakowicz <dwysakow...@apache.org> > <dwysakow...@apache.org> > wrote: > > > Hi all, > > Few points from my side: > > 1. I like the idea of simplifying the experience for first time users. > As for production use cases I share Jark's opinion that in this case I > would expect users to combine their distribution manually. I think in > such scenarios it is important to understand interconnections. > Personally I'd expect the slimmest possible distribution that I can > extend further with what I need in my production scenario. > > 2. I think there is also the problem that the matrix of possible > combinations that can be useful is already big. Do we want to have a > distribution for: > > SQL users: which connectors should we include? should we include > hive? which other catalog? > > DataStream users: which connectors should we include? > > For both of the above should we include yarn/kubernetes? > > I would opt for providing only the "slim" distribution as a release > artifact. > > 3. However, as I said I think its worth investigating how we can improve > users experience. What do you think of providing a tool, could be e.g. a > shell script that constructs a distribution based on users choice. I > think that was also what Chesnay mentioned as "tooling to > assemble custom distributions" In the end how I see the difference > between a slim and fat distribution is which jars do we put into the > lib, right? It could have a few "screens". > > 1. Which API are you interested in: > a. SQL API > b. DataStream API > > > 2. [SQL] Which connectors do you want to use? [multichoice]: > a. Kafka > b. Elasticsearch > ... > > 3. [SQL] Which catalog you want to use? > > ... > > Such a tool would download all the dependencies from maven and put them > into the correct folder. In the future we can extend it with additional > rules e.g. kafka-0.9 cannot be chosen at the same time with > kafka-universal etc. > > The benefit of it would be that the distribution that we release could > remain "slim" or we could even make it slimmer. I might be missing > something here though. > > Best, > > Dawdi > > On 16/04/2020 11:02, Aljoscha Krettek wrote: > > I want to reinforce my opinion from earlier: This is about improving > the situation both for first-time users and for experienced users that > want to use a Flink dist in production. The current Flink dist is too > "thin" for first-time SQL users and it is too "fat" for production > users, that is where serving no-one properly with the current > middle-ground. That's why I think introducing those specialized > "spins" of Flink dist would be good. > > By the way, at some point in the future production users might not > even need to get a Flink dist anymore. They should be able to have > Flink as a dependency of their project (including the runtime) and > then build an image from this for Kubernetes or a fat jar for YARN. > > Aljoscha > > On 15.04.20 18:14, wenlong.lwl wrote: > > Hi all, > > Regarding slim and fat distributions, I think different kinds of jobs > may > prefer different type of distribution: > > For DataStream job, I think we may not like fat distribution > > containing > > connectors because user would always need to depend on the connector > > in > > user code, it is easy to include the connector jar in the user lib. > > Less > > jar in lib means less class conflicts and problems. > > For SQL job, I think we are trying to encourage user to user pure > sql(DDL + > DML) to construct their job, In order to improve user experience, It > may be > important for flink, not only providing as many connector jar in > distribution as possible especially the connector and format we have > well > documented, but also providing an mechanism to load connectors > according > to the DDLs, > > So I think it could be good to place connector/format jars in some > dir like > opt/connector which would not affect jobs by default, and introduce a > mechanism of dynamic discovery for SQL. > > Best, > Wenlong > > On Wed, 15 Apr 2020 at 22:46, Jingsong Li <jingsongl...@gmail.com> > <jingsongl...@gmail.com> > wrote: > > > Hi, > > I am thinking both "improve first experience" and "improve production > experience". > > I'm thinking about what's the common mode of Flink? > Streaming job use Kafka? Batch job use Hive? > > Hive 1.2.1 dependencies can be compatible with most of Hive server > versions. So Spark and Presto have built-in Hive 1.2.1 dependency. > Flink is currently mainly used for streaming, so let's not talk > about hive. > > For streaming jobs, first of all, the jobs in my mind is (related to > connectors): > - ETL jobs: Kafka -> Kafka > - Join jobs: Kafka -> DimJDBC -> Kafka > - Aggregation jobs: Kafka -> JDBCSink > So Kafka and JDBC are probably the most commonly used. Of course, > > also > > includes CSV, JSON's formats. > So when we provide such a fat distribution: > - With CSV, JSON. > - With flink-kafka-universal and kafka dependencies. > - With flink-jdbc. > Using this fat distribution, most users can run their jobs well. > > (jdbc > > driver jar required, but this is very natural to do) > Can these dependencies lead to kinds of conflicts? Only Kafka may > > have > > conflicts, but if our goal is to use kafka-universal to support all > Kafka > versions, it is hopeful to target the vast majority of users. > > We don't want to plug all jars into the fat distribution. Only need > less > conflict and common. of course, it is a matter of consideration to > > put > > which jar into fat distribution. > We have the opportunity to facilitate the majority of users, but > also left > opportunities for customization. > > Best, > Jingsong Lee > > On Wed, Apr 15, 2020 at 10:09 PM Jark Wu <imj...@gmail.com> > <imj...@gmail.com> wrote: > > > Hi, > > I think we should first reach an consensus on "what problem do we > want to > solve?" > (1) improve first experience? or (2) improve production experience? > > As far as I can see, with the above discussion, I think what we > want to > solve is the "first experience". > And I think the slim jar is still the best distribution for > production, > because it's easier to assembling jars > than excluding jars and can avoid potential class conflicts. > > If we want to improve "first experience", I think it make sense to > have a > fat distribution to give users a more smooth first experience. > But I would like to call it "playground distribution" or something > like > that to explicitly differ from the "slim production-purpose > > distribution". > > The "playground distribution" can contains some widely used jars, > > like > > universal-kafka-sql-connector, elasticsearch7-sql-connector, avro, > json, > csv, etc.. > Even we can provide a playground docker which may contain the fat > distribution, python3, and hive. > > Best, > Jark > > > On Wed, 15 Apr 2020 at 21:47, Chesnay Schepler <ches...@apache.org> > <ches...@apache.org> > > wrote: > > I don't see a lot of value in having multiple distributions. > > The simple reality is that no fat distribution we could provide > > would > > satisfy all use-cases, so why even try. > If users commonly run into issues for certain jars, then maybe > > those > > should be added to the current distribution. > > Personally though I still believe we should only distribute a slim > version. I'd rather have users always add required jars to the > distribution than only when they go outside our "expected" > > use-cases. > > Then we might finally address this issue properly, i.e., tooling to > assemble custom distributions and/or better error messages if > Flink-provided extensions cannot be found. > > On 15/04/2020 15:23, Kurt Young wrote: > > Regarding to the specific solution, I'm not sure about the "fat" > > and > > "slim" > > solution though. I get the idea > that we can make the slim one even more lightweight than current > distribution, but what about the "fat" > one? Do you mean that we would package all connectors and formats > > into > > this? I'm not sure if this is > feasible. For example, we can't put all versions of kafka and hive > connector jars into lib directory, and > we also might need hadoop jars when using filesystem connector to > > access > > data from HDFS. > > So my guess would be we might hand-pick some of the most > > frequently > > used > > connectors and formats > into our "lib" directory, like kafka, csv, json metioned above, > > and > > still > > leave some other connectors out of it. > If this is the case, then why not we just provide this > > distribution > > to > > user? I'm not sure i get the benefit of > providing another super "slim" jar (we have to pay some costs to > > provide > > another suit of distribution). > > What do you think? > > Best, > Kurt > > > On Wed, Apr 15, 2020 at 7:08 PM Jingsong Li < > > jingsongl...@gmail.com > > wrote: > > Big +1. > > I like "fat" and "slim". > > For csv and json, like Jark said, they are quite small and don't > > have > > other > > dependencies. They are important to kafka connector, and > > important > > to upcoming file system connector too. > So can we move them to both "fat" and "slim"? They're so > > important, > > and > > they're so lightweight. > > Best, > Jingsong Lee > > On Wed, Apr 15, 2020 at 4:53 PM godfrey he <godfre...@gmail.com> > <godfre...@gmail.com> > > wrote: > > Big +1. > This will improve user experience (special for Flink new users). > We answered so many questions about "class not found". > > Best, > Godfrey > > Dian Fu <dian0511...@gmail.com> <dian0511...@gmail.com> 于2020年4月15日周三 > 下午4:30写道： > > > +1 to this proposal. > > Missing connector jars is also a big problem for PyFlink users. > > Currently, > > after a Python user has installed PyFlink using `pip`, he has > > to > > manually > > copy the connector fat jars to the PyFlink installation > > directory > > for > > the > > connectors to be used if he wants to run jobs locally. This > > process > > is > > very > > confuse for users and affects the experience a lot. > > Regards, > Dian > > > 在 2020年4月15日，下午3:51，Jark Wu <imj...@gmail.com> <imj...@gmail.com> 写道： > > +1 to the proposal. I also found the "download additional jar" > > step > > is > > really verbose when I prepare webinars. > > At least, I think the flink-csv and flink-json should in the > > distribution, > > they are quite small and don't have other dependencies. > > Best, > Jark > > On Wed, 15 Apr 2020 at 15:44, Jeff Zhang <zjf...@gmail.com> <zjf...@gmail.com> > > wrote: > > Hi Aljoscha, > > Big +1 for the fat flink distribution, where do you plan to > > put > > these > > connectors ? opt or lib ? > > Aljoscha Krettek <aljos...@apache.org> <aljos...@apache.org> 于2020年4月15日周三 > 下午3:30写道： > > > Hi Everyone, > > I'd like to discuss about releasing a more full-featured > > Flink > > distribution. The motivation is that there is friction for > > SQL/Table > > API > > users that want to use Table connectors which are not there > > in > > the > > current Flink Distribution. For these users the workflow is > > currently > > roughly: > > - download Flink dist > - configure csv/Kafka/json connectors per configuration > - run SQL client or program > - decrypt error message and research the solution > - download additional connector jars > - program works correctly > > I realize that this can be made to work but if every SQL > > user > > has > > this > > as their first experience that doesn't seem good to me. > > My proposal is to provide two versions of the Flink > > Distribution > > in > > the > > future: "fat" and "slim" (names to be discussed): > > - slim would be even trimmer than todays distribution > - fat would contain a lot of convenience connectors (yet > > to > > be > > determined which one) > > And yes, I realize that there are already more dimensions of > > Flink > > releases (Scala version and Java version). > > For background, our current Flink dist has these in the opt > > directory: > > - flink-azure-fs-hadoop-1.10.0.jar > - flink-cep-scala_2.12-1.10.0.jar > - flink-cep_2.12-1.10.0.jar > - flink-gelly-scala_2.12-1.10.0.jar > - flink-gelly_2.12-1.10.0.jar > - flink-metrics-datadog-1.10.0.jar > - flink-metrics-graphite-1.10.0.jar > - flink-metrics-influxdb-1.10.0.jar > - flink-metrics-prometheus-1.10.0.jar > - flink-metrics-slf4j-1.10.0.jar > - flink-metrics-statsd-1.10.0.jar > - flink-oss-fs-hadoop-1.10.0.jar > - flink-python_2.12-1.10.0.jar > - flink-queryable-state-runtime_2.12-1.10.0.jar > - flink-s3-fs-hadoop-1.10.0.jar > - flink-s3-fs-presto-1.10.0.jar > - > > flink-shaded-netty-tcnative-dynamic-2.0.25.Final-9.0.jar > > - flink-sql-client_2.12-1.10.0.jar > - flink-state-processor-api_2.12-1.10.0.jar > - flink-swift-fs-hadoop-1.10.0.jar > > Current Flink dist is 267M. If we removed everything from > > opt > > we > > would > > go down to 126M. I would reccomend this, because the large > > majority > > of > > the files in opt are probably unused. > > What do you think? > > Best, > Aljoscha > > > > -- > Best Regards > > Jeff Zhang > > > -- > Best, Jingsong Lee > > > -- > Best, Jingsong Lee > > > >
