Hello Almog, I left a comment in the PR before I got to read the newest updates from this thread. My 2c:
1. I liked the idea of delaying the instantiation of StoreBuiler from suppliers after the Topology is created. It has been a bit annoying for many other features we were trying back then. The only thing is, we need to check when we call Topology.describe() which gets a TopologyDescription, does that reveal anything about the source of truth store impl types already; if it does not, then we are good to go. 2. I originally thought (and commented in the PR) that maybe we can just add this new func "resolveDslStoreSuppliers" into StreamsConfig directly and mark it as EVOLVING, because I was not clear that we are trying to do 1) above. Now I'm leaning more towards what you proposed. But I still have a question in mind: even after we've done https://github.com/apache/kafka/pull/14548 later, don't we still need some interface that user's can call to get the actual instantiated store supplier for cases where some external custom logic, like an external controller / scheduler which is developed by a different group of people rather than the Streams app developers themselves, that can only turn on certain features after learning the actual store impl suppliers used? Guozhang On Sat, Nov 18, 2023 at 2:46 PM Almog Gavra <almog.ga...@gmail.com> wrote: > > Hello Everyone - one more minor change to the KIP that came up during > implementation (reflected in the KIP itself). I will be adding the method > below to TopologyConfig. This allows us to determine whether or not the > DslStoreSuppliers was explicitly passed in via either > DSL_STORE_SUPPLIERS_CLASS_CONFIG or DEFAULT_DSL_STORE_CONFIG (if it was not > explicitly passed in, we will use the one that is configured in > StreamsConfig, or the default value of RocksDBDslStoreSuppliers). > > See the discussion on the PR ( > https://github.com/apache/kafka/pull/14648#discussion_r1394939779) for more > context. Ideally this would be an internal utility method but there's no > clean way to get that done now, so the goal was to minimize the surface > area of what's being exposed (as opposed to exposing a generic method like > isOverridden(String config). > > /** > * @return the DslStoreSuppliers if the value was explicitly configured > (either by > * {@link StreamsConfig#DEFAULT_DSL_STORE} or {@link > StreamsConfig#DSL_STORE_SUPPLIERS_CLASS_CONFIG}) > */ > public Optional<DslStoreSuppliers> resolveDslStoreSuppliers(); > > On Fri, Nov 3, 2023 at 10:48 AM Matthias J. Sax <mj...@apache.org> wrote: > > > Thanks. Will take a look into the PR. > > > > I don't have any objection to the goal; contrary! It's very annoying > > what we have right now, and if we can improve it, I am totally in favor > > of it. > > > > > > -Matthias > > > > On 11/3/23 8:47 AM, Almog Gavra wrote: > > > Good question :) I have a PR for it already here: > > > https://github.com/apache/kafka/pull/14659. The concept is to wrap the > > > suppliers with an interface that allows for delayed creation of the > > > StoreBuilder instead of creating the StoreBuilder from the suppliers > > right > > > away. Happy to get on a quick call to outline the implementation strategy > > > if you'd like, but hopefully you have no objections to the goal! > > > > > > On Thu, Nov 2, 2023 at 8:44 PM Matthias J. Sax <mj...@apache.org> wrote: > > > > > >> Almog, > > >> > > >> can you explain how you intent to implement this change? It's not clear > > >> to me, how we could do this? > > >> > > >> When we call `StreasmBuilder.build()` it will give us a already fully > > >> wired `Topology`, including all store suppliers needed. I don't see a > > >> clean way how we could change the store supplier after the fact? > > >> > > >> > > >> -Matthias > > >> > > >> On 11/2/23 5:11 PM, Almog Gavra wrote: > > >>> Hello everyone - I updated the KIP to also include the following > > >>> modification: > > >>> > > >>> Both the new dsl.store.suppliers.class and the old default.dsl.store > > >> will > > >>> now respect the configurations when passed in via > > >> KafkaStreams#new(Topology, > > >>> StreamsConfig) (and other related constructors) instead of only being > > >>> respected when passed in to the initial > > StoreBuilder#new(TopologyConfig) > > >>> (though it will be respected if passed in via the original path as > > well). > > >>> > > >>> I was honestly a bit shocked this wasn't the case with the original KIP > > >>> that introduced default.dsl.store! > > >>> > > >>> On Fri, Jul 28, 2023 at 4:55 PM Almog Gavra <almog.ga...@gmail.com> > > >> wrote: > > >>> > > >>>> OK! I think I got everything, but I'll give the KIP another read with > > >>>> fresh eyes later. Just a reminder that the voting is open, so go out > > and > > >>>> exercise your civic duty! ;) > > >>>> > > >>>> - Almog > > >>>> > > >>>> On Fri, Jul 28, 2023 at 10:38 AM Almog Gavra <almog.ga...@gmail.com> > > >>>> wrote: > > >>>> > > >>>>> Thanks Guozhang & Sophie: > > >>>>> > > >>>>> A2. Will clarify in the KIP > > >>>>> A3. Will change back to the deprecated version! > > >>>>> A5. Seems like I'm outnumbered... DslStoreSuppliers it is. > > >>>>> > > >>>>> Will update the KIP today. > > >>>>> > > >>>>> - Almog > > >>>>> > > >>>>> On Thu, Jul 27, 2023 at 12:42 PM Guozhang Wang < > > >>>>> guozhang.wang...@gmail.com> wrote: > > >>>>> > > >>>>>> Yes, that sounds right to me. Thanks Sophie. > > >>>>>> > > >>>>>> On Thu, Jul 27, 2023 at 12:35 PM Sophie Blee-Goldman > > >>>>>> <ableegold...@gmail.com> wrote: > > >>>>>>> > > >>>>>>> A2: Guozhang, just to close the book on the ListValue store thing, > > I > > >>>>>> fully > > >>>>>>> agree it seems like overreach > > >>>>>>> to expose/force this on users, especially if it's fully internal > > >>>>>> today. But > > >>>>>>> just to make sure we're on the same > > >>>>>>> page here, you're still ok with this KIP fixing the API gap that > > >> exists > > >>>>>>> today, in which these stores cannot be > > >>>>>>> customized by the user at all? > > >>>>>>> > > >>>>>>> In other words, after this KIP, the new behavior for the ListValue > > >>>>>> store in > > >>>>>>> a stream join will be: > > >>>>>>> > > >>>>>>> S1: First, check if the user passed in a `DSLStoreSuppliers` (or > > >>>>>> whatever > > >>>>>>> the name will be) to the > > >>>>>>> StreamJoined config object, and use that to obtain the > > >>>>>>> KVStoreSupplier for this ListValue store > > >>>>>>> > > >>>>>>> S2: If none was provided, check if the user has set a default > > >>>>>>> DSLStoreSuppliers via the new config, > > >>>>>>> and use that to get the KVStoreSupplier if so > > >>>>>>> > > >>>>>>> S3: If neither is set, fall back to the original logic as it is > > >> today, > > >>>>>>> which is to pass in a KVStoreSupplier > > >>>>>>> that is hard-coded to be either RocksDB or InMemory, > > based on > > >>>>>> what > > >>>>>>> is returned for the #persistent > > >>>>>>> API by the StreamJoined's WindowStoreSupplier > > >>>>>>> > > >>>>>>> Does that sound right? We can clarify this further in the KIP if > > need > > >>>>>> be > > >>>>>>> > > >>>>>>> On Thu, Jul 27, 2023 at 10:48 AM Guozhang Wang < > > >>>>>> guozhang.wang...@gmail.com> > > >>>>>>> wrote: > > >>>>>>> > > >>>>>>>> Hi all, > > >>>>>>>> > > >>>>>>>> Like Almog's secretary as well! Just following up on that index: > > >>>>>>>> > > >>>>>>>> A2: I'm also happy without introducing versioned KV in this KIP > > as I > > >>>>>>>> would envision it to be introduced as new params into the > > >>>>>>>> KeyValuePluginParams in the future. And just to clarify on > > Sophie's > > >>>>>>>> previous comment, I think ListStore should not be exposed in this > > >> API > > >>>>>>>> until we see it as a common usage and hence would want to (again, > > we > > >>>>>>>> need to think very carefully since it would potentially ask all > > >>>>>>>> implementers to adopt) move it from the internal category to the > > >>>>>>>> public interface category. As for now, I think only having kv / > > >>>>>> window > > >>>>>>>> / session as public store types is fine. > > >>>>>>>> > > >>>>>>>> A3: Seems I was not making myself very clear at the beginning :P > > The > > >>>>>>>> major thing that I'd actually like to avoid having two configs > > >>>>>>>> co-exist for the same function since it will be a confusing > > learning > > >>>>>>>> curve for users, and hence what I was proposing is to just have > > the > > >>>>>>>> newly introduced interface but not introducing a new config, and I > > >>>>>>>> realized now that it is actually more aligned with the CUSTOM idea > > >>>>>>>> where the ordering would be looking at config first, and then the > > >>>>>>>> interface. I blushed as I read Almog likes it.. After thinking > > about > > >>>>>>>> it twice, I'm now a bit leaning towards just deprecating the old > > >>>>>>>> config with the new API+config as well. > > >>>>>>>> > > >>>>>>>> A5: Among the names we have been discussed so far: > > >>>>>>>> > > >>>>>>>> DslStorePlugin > > >>>>>>>> StoreTypeSpec > > >>>>>>>> StoreImplSpec > > >>>>>>>> DslStoreSuppliers > > >>>>>>>> > > >>>>>>>> I am in favor of DslStoreSuppliers as well as a restrictiveness on > > >>>>>> its > > >>>>>>>> scope, just to echo Bruno's comments above. > > >>>>>>>> > > >>>>>>>> > > >>>>>>>> > > >>>>>>>> Guozhang > > >>>>>>>> > > >>>>>>>> On Thu, Jul 27, 2023 at 4:15 AM Bruno Cadonna <cado...@apache.org > > > > > >>>>>> wrote: > > >>>>>>>>> > > >>>>>>>>> Hi, > > >>>>>>>>> > > >>>>>>>>> A5. I have to admit that > > >>>>>>>>> "If we envision extending this beyond just StoreSupplier types, > > it > > >>>>>> could > > >>>>>>>>> be a good option." > > >>>>>>>>> is scaring me a bit. > > >>>>>>>>> I am wondering what would be an example for such an extension? > > >>>>>>>>> In general, I would propose to limit the scope of a config. In > > >>>>>> this case > > >>>>>>>>> the config should provide suppliers for state stores for the DSL. > > >>>>>>>>> > > >>>>>>>>> BTW, maybe it is a good idea to let DslStorePlugin extend > > >>>>>> Configurable. > > >>>>>>>>> > > >>>>>>>>> Best, > > >>>>>>>>> Bruno > > >>>>>>>>> > > >>>>>>>>> On 7/27/23 2:15 AM, Sophie Blee-Goldman wrote: > > >>>>>>>>>> Thanks for the feedback Bruno -- sounds like we're getting close > > >>>>>> to a > > >>>>>>>> final > > >>>>>>>>>> consensus here. > > >>>>>>>>>> It sounds like the two main (only?) semi-unresolved questions > > >>>>>> that > > >>>>>>>> still > > >>>>>>>>>> have differing > > >>>>>>>>>> opinions floating around are whether to deprecate the old > > >>>>>> config, and > > >>>>>>>> what > > >>>>>>>>>> to name the new config > > >>>>>>>>>> + interface. > > >>>>>>>>>> > > >>>>>>>>>> Although I won't personally push back on any of the options > > >>>>>> listed > > >>>>>>>> above, > > >>>>>>>>>> here's my final two cents: > > >>>>>>>>>> > > >>>>>>>>>> A3. I'm still a firm believer in deprecating the old config, and > > >>>>>> agree > > >>>>>>>>>> wholeheartedly with what Bruno said. > > >>>>>>>>>> > > >>>>>>>>>> A5. I also wasn't crazy about "Plugin" at first, but I will > > >>>>>> admit it's > > >>>>>>>>>> grown on me. I think it rubbed me the wrong > > >>>>>>>>>> way at first because it's just not part of the standard > > >>>>>> vocabulary in > > >>>>>>>>>> Streams so far. If we envision extending > > >>>>>>>>>> this beyond just StoreSupplier types, it could be a good option. > > >>>>>>>>>> DSLStoreSuppliers does make a lot of sense, > > >>>>>>>>>> though. > > >>>>>>>>>> > > >>>>>>>>>> To throw out a few more ideas in case any of them stick, what > > >>>>>> about > > >>>>>>>>>> something like DSLStoreFormat or > > >>>>>>>>>> DSLStorageType, or even DSLStorageEngine? Or even > > >>>>>> DSLStoreFactory -- > > >>>>>>>> the > > >>>>>>>>>> Stores class is described as > > >>>>>>>>>> a "factory" (though not named so) and, to me, is actually quite > > >>>>>>>> comparable > > >>>>>>>>>> -- both are providers not of the > > >>>>>>>>>> stores themselves, but of the basic building blocks of Stores > > (eg > > >>>>>>>>>> StoreSuppliers) > > >>>>>>>>>> > > >>>>>>>>>> Ultimately fine with anything though. We should try not to drag > > >>>>>> out > > >>>>>>>> the KIP > > >>>>>>>>>> discussion too long once it's down > > >>>>>>>>>> to just nits :P > > >>>>>>>>>> > > >>>>>>>>>> Cheers, > > >>>>>>>>>> Sophie > > >>>>>>>>>> > > >>>>>>>>>> > > >>>>>>>>>> > > >>>>>>>>>> On Wed, Jul 26, 2023 at 8:04 AM Almog Gavra < > > >>>>>> almog.ga...@gmail.com> > > >>>>>>>> wrote: > > >>>>>>>>>> > > >>>>>>>>>>> Thanks for the comments Bruno! > > >>>>>>>>>>> > > >>>>>>>>>>> A3. Oops... I think I didn't do a great job updating the KIP to > > >>>>>>>> reflect > > >>>>>>>>>>> Guozhang's suggestion. This seems like the last point of > > >>>>>> contention, > > >>>>>>>> where > > >>>>>>>>>>> we have two options: > > >>>>>>>>>>> > > >>>>>>>>>>> 1. Deprecate the config entirely and replace IN_MEMORY/ROCKSDB > > >>>>>> with > > >>>>>>>>>>> implementations of the DslStorePlugin > > >>>>>>>>>>> 2. (What's currently in the KIP) Introduce a new config which > > >>>>>>>> defaults to > > >>>>>>>>>>> DefaultDslStorePlugin and only the DefaultDslStorePlugin will > > >>>>>> respect > > >>>>>>>> the > > >>>>>>>>>>> old default.store.type config > > >>>>>>>>>>> > > >>>>>>>>>>> I'm happy with either, I'll keep the KIP with (2) for now as > > >>>>>> that > > >>>>>>>> seemed > > >>>>>>>>>>> like the result of the previous discussion but I have no > > problem > > >>>>>>>> changing > > >>>>>>>>>>> it back to (1) which was the original proposal. > > >>>>>>>>>>> > > >>>>>>>>>>> A5. I like "DslStorePlugin" because it leaves room for > > >>>>>> configuring > > >>>>>>>>>>> implementations beyond just supplying stores (e.g. we could > > >>>>>> introduce > > >>>>>>>> a > > >>>>>>>>>>> `configure()` method etc...). I'll keep it as is for now (and > > >>>>>> change > > >>>>>>>>>>> Materialized/Stores API sections - thanks for catching that)! I > > >>>>>> don't > > >>>>>>>> feel > > >>>>>>>>>>> too strongly and wouldn't dig my heels in if most people > > >>>>>> preferred > > >>>>>>>>>>> "DslStoreSuppliers" (I don't love DslStores as it resembles the > > >>>>>> Stores > > >>>>>>>>>>> class to closely in name and they're a little different). > > >>>>>>>>>>> > > >>>>>>>>>>> A6. Yup, that's the suggestion. > > >>>>>>>>>>> > > >>>>>>>>>>> - Almog > > >>>>>>>>>>> > > >>>>>>>>>>> On Wed, Jul 26, 2023 at 6:38 AM Bruno Cadonna < > > >>>>>> cado...@apache.org> > > >>>>>>>> wrote: > > >>>>>>>>>>> > > >>>>>>>>>>>> Hi, > > >>>>>>>>>>>> > > >>>>>>>>>>>> Sorry for being late to the party! > > >>>>>>>>>>>> > > >>>>>>>>>>>> A1: I agree with Sophie, Guozhang, and Almog not to block the > > >>>>>> KIP on > > >>>>>>>>>>>> gaps in the implementation. > > >>>>>>>>>>>> > > >>>>>>>>>>>> A2: I am happy with not considering anything special w.r.t. > > >>>>>> versioned > > >>>>>>>>>>>> state stores in this KIP. > > >>>>>>>>>>>> > > >>>>>>>>>>>> A3: Here I agree with Sophie to deprecate the old config. I > > >>>>>> would > > >>>>>>>> also > > >>>>>>>>>>>> not use config value CUSTOM. Having two configs that sometimes > > >>>>>>>> depend on > > >>>>>>>>>>>> each other to configure one single concept seems confusing to > > >>>>>> me. I > > >>>>>>>> see > > >>>>>>>>>>>> future me looking at default.dsl.store = IN_MEMORY and > > >>>>>> wondering why > > >>>>>>>>>>>> something is written to disk because I did not check config > > >>>>>>>>>>>> dsl.store.plugin.class? > > >>>>>>>>>>>> BTW, the KIP in its current version is not clear about whether > > >>>>>>>>>>>> default.dsl.store will be deprecated or not. In > > "Compatibility, > > >>>>>>>>>>>> Deprecation, and Migration Plan" it says default.dsl.store > > >>>>>> will be > > >>>>>>>>>>>> deprecated but in "Configuration" default.dsl.store seems to > > >>>>>> be an > > >>>>>>>>>>>> essential part of the configuration. > > >>>>>>>>>>>> > > >>>>>>>>>>>> A4: I agree > > >>>>>>>>>>>> > > >>>>>>>>>>>> A5: I do not completely like the name "DslStorePlugin". What > > >>>>>> about > > >>>>>>>>>>>> naming it simply "DslStores" or "DslStoreSuppliers"? If we > > >>>>>> decide to > > >>>>>>>>>>>> rename we should also rename dsl.store.plugin.class to > > >>>>>>>>>>>> dsl.store.suppliers.class or similar. > > >>>>>>>>>>>> BTW, I think you missed to rename some occurrences in section > > >>>>>>>>>>>> "Materialized API" especially in the code section > > >>>>>> "Stores.java". > > >>>>>>>>>>>> > > >>>>>>>>>>>> A6: Actually I am not sure if I completely follow here. Is > > >>>>>> this about > > >>>>>>>>>>>> the static methods in class Stores? If yes, I agree with Almog > > >>>>>> to > > >>>>>>>> keep > > >>>>>>>>>>>> this out of the KIP. > > >>>>>>>>>>>> > > >>>>>>>>>>>> Best, > > >>>>>>>>>>>> Bruno > > >>>>>>>>>>>> > > >>>>>>>>>>>> On 7/26/23 5:20 AM, Almog Gavra wrote: > > >>>>>>>>>>>>> I have updated the KIP with the points as discussed above. > > >>>>>>>> @Guozhang, > > >>>>>>>>>>> the > > >>>>>>>>>>>>> suggested configuration makes it a little more awkward around > > >>>>>> the > > >>>>>>>>>>>>> Materialized.as and Materialized.withStoreType APIs than it > > >>>>>> was > > >>>>>>>> when we > > >>>>>>>>>>>>> were totally deprecating the old configuration. Let me know > > >>>>>> what you > > >>>>>>>>>>>> think. > > >>>>>>>>>>>>> > > >>>>>>>>>>>>> I will open the voting tomorrow! Thanks again everyone for > > the > > >>>>>>>>>>>> discussion. > > >>>>>>>>>>>>> > > >>>>>>>>>>>>> Cheers, > > >>>>>>>>>>>>> Almog > > >>>>>>>>>>>>> > > >>>>>>>>>>>>> On Tue, Jul 25, 2023 at 9:20 AM Almog Gavra < > > >>>>>> almog.ga...@gmail.com> > > >>>>>>>>>>>> wrote: > > >>>>>>>>>>>>> > > >>>>>>>>>>>>>> Glad you like my KIP-secretary skills ;) > > >>>>>>>>>>>>>> > > >>>>>>>>>>>>>> A2. I'm definitely happy to take your suggestion here and > > >>>>>> not do > > >>>>>>>>>>>> anything > > >>>>>>>>>>>>>> special w.r.t. Versioned stores, I think it makes sense > > >>>>>> especially > > >>>>>>>> if > > >>>>>>>>>>> we > > >>>>>>>>>>>>>> consider them implementation details of a specific store > > >>>>>> type. > > >>>>>>>>>>>>>> > > >>>>>>>>>>>>>> At EOD I'll update the KIP with all of these changes and if > > >>>>>> the > > >>>>>>>>>>>>>> discussion is silent I'll open a vote tomorrow morning. > > >>>>>>>>>>>>>> > > >>>>>>>>>>>>>> Cheers, > > >>>>>>>>>>>>>> Almog > > >>>>>>>>>>>>>> > > >>>>>>>>>>>>>> On Mon, Jul 24, 2023 at 2:02 PM Sophie Blee-Goldman < > > >>>>>>>>>>>>>> ableegold...@gmail.com> wrote: > > >>>>>>>>>>>>>> > > >>>>>>>>>>>>>>> Awesome summary (seriously) -- would you kindly offer your > > >>>>>>>>>>>> organizational > > >>>>>>>>>>>>>>> skills to every ongoing KIP from henceforth? We need you :P > > >>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>> A few answers/comments: > > >>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>> A2: I think there is a 3rd sub-option here, which is to > > >>>>>> leave > > >>>>>>>>>>>>>>> versioned-ness out of this KIP entirely, return only the > > >>>>>>>>>>> non-versioned > > >>>>>>>>>>>>>>> stores for now, and then switch over to the versioned > > stores > > >>>>>>>> (only) > > >>>>>>>>>>>> when > > >>>>>>>>>>>>>>> the time comes to flip the switch on making them the > > default > > >>>>>>>> across > > >>>>>>>>>>> the > > >>>>>>>>>>>>>>> DSL. This has the advantage of retaining the current > > >>>>>>>>>>> behavior/semantics > > >>>>>>>>>>>>>>> and > > >>>>>>>>>>>>>>> provides a clear way to transition smoothly in the future, > > >>>>>> since > > >>>>>>>> it > > >>>>>>>>>>>> seems > > >>>>>>>>>>>>>>> we will want to cut to all versioned state stores rather > > >>>>>> than > > >>>>>>>> offer > > >>>>>>>>>>>> users > > >>>>>>>>>>>>>>> a > > >>>>>>>>>>>>>>> choice between versioned or non-versioned stores going > > >>>>>> forward > > >>>>>>>>>>>> (similar to > > >>>>>>>>>>>>>>> how we only offer timestamped stores presently, and have > > >>>>>>>> completely > > >>>>>>>>>>>>>>> replaced non-timestamped stores in the DSL.) . In both the > > >>>>>>>>>>> timestamped > > >>>>>>>>>>>> and > > >>>>>>>>>>>>>>> versioned cases, the old stores are/will still be available > > >>>>>> or > > >>>>>>>>>>>> accessible > > >>>>>>>>>>>>>>> to users via the bare StoreSuppliers, should they somehow > > >>>>>> desire > > >>>>>>>> or > > >>>>>>>>>>>>>>> require > > >>>>>>>>>>>>>>> the old store type. Ultimately, I think either this or > > >>>>>> option (1) > > >>>>>>>>>>>> would be > > >>>>>>>>>>>>>>> preferable, though I think it should be up to Matthias or > > >>>>>> anyone > > >>>>>>>> else > > >>>>>>>>>>>>>>> involved in the versioned stores feature to decide which > > >>>>>> approach > > >>>>>>>>>>> makes > > >>>>>>>>>>>>>>> sense in the context of that feature's future plans. > > >>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>> A3: sounds reasonable to me > > >>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>> A5: Also sounds fine to me, though I'll let others chime in > > >>>>>>>> with/if > > >>>>>>>>>>>> they > > >>>>>>>>>>>>>>> have an alternative suggestion/preference. I guess the > > other > > >>>>>>>>>>> contender > > >>>>>>>>>>>>>>> would be something like DSLStoreImpl or something like > > that? > > >>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>> On Mon, Jul 24, 2023 at 9:36 AM Almog Gavra < > > >>>>>>>> almog.ga...@gmail.com> > > >>>>>>>>>>>>>>> wrote: > > >>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> Lots of thoughts! Happy to see the thriving discussion on > > >>>>>> this > > >>>>>>>> post > > >>>>>>>>>>> - > > >>>>>>>>>>>>>>> lots > > >>>>>>>>>>>>>>>> going on so I'm trying to enumerate them to keep things > > >>>>>> organized > > >>>>>>>>>>>>>>> (prefix > > >>>>>>>>>>>>>>>> "A" for "Almog" so we can use numbers in responses for > > >>>>>> other > > >>>>>>>> things > > >>>>>>>>>>>> ;P). > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> A1. Question around closing implementation gaps (e.g. no > > >>>>>> rocks > > >>>>>>>> based > > >>>>>>>>>>>>>>>> suppression store) > > >>>>>>>>>>>>>>>> A2. Specifically how to handle Versioned stores > > >>>>>>>>>>>>>>>> A3. Configuration (new config/reuse old one + new one and > > >>>>>>>> ordering > > >>>>>>>>>>> of > > >>>>>>>>>>>>>>>> config resolution) > > >>>>>>>>>>>>>>>> A4. Drawing a line between what is implementation detail > > >>>>>> (not > > >>>>>>>>>>> exposed > > >>>>>>>>>>>> in > > >>>>>>>>>>>>>>>> API) and what is customizable (exposed in API) > > >>>>>>>>>>>>>>>> A5. Naming of StoreTypeSpec > > >>>>>>>>>>>>>>>> A6. Param classes in StoreBuilders > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> ------------------------------ > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> Here are summaries for where it seems each of these stands > > >>>>>>>> (trying > > >>>>>>>>>>> not > > >>>>>>>>>>>>>>> to > > >>>>>>>>>>>>>>>> add any additional opinion yet): > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> A1. Sophie/Guozhang/Me (if I count hah!) seem to agree > > >>>>>> that it is > > >>>>>>>>>>>> worth > > >>>>>>>>>>>>>>>> pushing this KIP through independently of the > > >>>>>> implementation > > >>>>>>>> gaps as > > >>>>>>>>>>>> it > > >>>>>>>>>>>>>>>> doesn't seem to move the intermediate state further from > > >>>>>> the end > > >>>>>>>>>>>> state. > > >>>>>>>>>>>>>>>> Matthias originally had some concerns. > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> A2. There's questions around whether versioned stores > > >>>>>> should be > > >>>>>>>>>>> their > > >>>>>>>>>>>>>>> own > > >>>>>>>>>>>>>>>> configurable option or whether they are an implementation > > >>>>>> detail > > >>>>>>>>>>> that > > >>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>> StoreSpec should decide. It seems like the discussion is > > >>>>>>>> converging > > >>>>>>>>>>>>>>> here, > > >>>>>>>>>>>>>>>> this should be an implementation detail. > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> A3. Matthias/Guozhang prefer adding CUSTOM and then having > > >>>>>> an > > >>>>>>>>>>>> additional > > >>>>>>>>>>>>>>>> config to determine the implementation. Sophie prefers > > >>>>>>>> deprecating > > >>>>>>>>>>> the > > >>>>>>>>>>>>>>> old > > >>>>>>>>>>>>>>>> config. Guozhang additional suggested flipping the > > >>>>>> resolution > > >>>>>>>> order > > >>>>>>>>>>>> such > > >>>>>>>>>>>>>>>> that the old config is only respected in a > > DefaultStoreSpec > > >>>>>>>>>>>>>>> implementation. > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> A4. This KIP (or rather, the discussion on the KIP) blurs > > >>>>>> the > > >>>>>>>> lines > > >>>>>>>>>>>>>>> between > > >>>>>>>>>>>>>>>> top level store types (KV, windowed, session) and the > > >>>>>> underlying > > >>>>>>>>>>>>>>>> implementation of them (timestamped, versioned, kv-list). > > >>>>>> It > > >>>>>>>> seems > > >>>>>>>>>>>>>>> everyone > > >>>>>>>>>>>>>>>> is in alignment to ensure that we keep these two things > > >>>>>> separate > > >>>>>>>> and > > >>>>>>>>>>>>>>> that > > >>>>>>>>>>>>>>>> the line is clearly delineated in the text of the KIP. > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> A5. Guozhang and Sophie agree that the current name > > >>>>>>>> StoreTypeSpec is > > >>>>>>>>>>>>>>>> misleading, as it's really an implementation spec, not a > > >>>>>> type > > >>>>>>>>>>>>>>>> specification. > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> A6. Agreement that this is an improvement, Sophie believes > > >>>>>> this > > >>>>>>>> can > > >>>>>>>>>>> be > > >>>>>>>>>>>>>>> done > > >>>>>>>>>>>>>>>> in a follow up but we should ensure our naming is good > > >>>>>> here so > > >>>>>>>>>>> there's > > >>>>>>>>>>>>>>> no > > >>>>>>>>>>>>>>>> conflicts down the line. > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> --------------------------------- > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> Ok, phew! Hopefully that covers it all! Now for my > > >>>>>> thoughts, > > >>>>>>>>>>> hopefully > > >>>>>>>>>>>>>>>> wrapping up some of these discussions: > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> A1. @Matthias - are you still hesitant here? What would > > >>>>>> you > > >>>>>>>> need to > > >>>>>>>>>>>> be > > >>>>>>>>>>>>>>>> convinced here? > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> A2. Since we are all in agreement that versioned stores > > >>>>>> should > > >>>>>>>> be an > > >>>>>>>>>>>>>>>> implementation detail, we have two options: > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> (1) we can extend the KVParams to include a parameter that > > >>>>>>>> indicates > > >>>>>>>>>>>>>>>> whether or not the store should be versioned > > >>>>>>>>>>>>>>>> (2) we can introduce a configuration for whether or not to > > >>>>>> use a > > >>>>>>>>>>>>>>> versioned > > >>>>>>>>>>>>>>>> store, and each implementation can choose to read/ignore > > >>>>>> that > > >>>>>>>> config > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> Any preferences? (1) would align more closely with what we > > >>>>>> are > > >>>>>>>> doing > > >>>>>>>>>>>>>>> today > > >>>>>>>>>>>>>>>> (they are a top-level concept in the Stores API). > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> A3. I like Guozhang's suggestion of making the "primary" > > >>>>>>>>>>> configuration > > >>>>>>>>>>>>>>> to > > >>>>>>>>>>>>>>>> be the new one, and then having a "DefaultStoreTypeSpec" > > >>>>>> (using > > >>>>>>>> the > > >>>>>>>>>>>> old > > >>>>>>>>>>>>>>>> naming) which respects the old configuration. That seems > > >>>>>> to solve > > >>>>>>>>>>>> nearly > > >>>>>>>>>>>>>>>> all the concerns (e.g. it'd be easy to see where the enum > > >>>>>> is used > > >>>>>>>>>>>>>>> because > > >>>>>>>>>>>>>>>> it would only be used within that one class instead of > > >>>>>> littered > > >>>>>>>>>>>>>>> throughout > > >>>>>>>>>>>>>>>> the code base). > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> @Sophie, unless you have objections here I will update the > > >>>>>> KIP > > >>>>>>>> to do > > >>>>>>>>>>>>>>> that. > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> A4. I will make these changes to the KIP to make it clear. > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> A5. I will rename it `DslStorePlugin` - any objections to > > >>>>>> this > > >>>>>>>> name? > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> A6. Let's punt this ;) I agree with everyone that this > > >>>>>> would be a > > >>>>>>>>>>>>>>> welcome > > >>>>>>>>>>>>>>>> improvement and that this KIP is aligned with moving in > > >>>>>> that > > >>>>>>>>>>>> direction. > > >>>>>>>>>>>>>>>> Given how much discussion there was on this KIP, which is > > >>>>>> minor > > >>>>>>>>>>>>>>> relative to > > >>>>>>>>>>>>>>>> making the changes to StoreBuilder API, I'd rather not tie > > >>>>>> the > > >>>>>>>> two > > >>>>>>>>>>>>>>>> together. > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> Cheers & Thanks everyone for the thoughts! > > >>>>>>>>>>>>>>>> - Almog > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> On Sun, Jul 23, 2023 at 5:15 PM Sophie Blee-Goldman < > > >>>>>>>>>>>>>>>> ableegold...@gmail.com> > > >>>>>>>>>>>>>>>> wrote: > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>> Guozhang: > > >>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>> On your 2nd point: > > >>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>> "impl types" (in hindsight it may not be a good name) > > for > > >>>>>>>> rocksdb > > >>>>>>>>>>> / > > >>>>>>>>>>>>>>>>> memory / custom, and we used "store types" for kv / > > >>>>>> windowed / > > >>>>>>>>>>>>>>> sessioned > > >>>>>>>>>>>>>>>>> etc, > > >>>>>>>>>>>>>>>>> First off, thanks so much for this clarification -- using > > >>>>>> "store > > >>>>>>>>>>>> type" > > >>>>>>>>>>>>>>>> here > > >>>>>>>>>>>>>>>>> was definitely making me uncomfortable as this usually > > >>>>>> refers > > >>>>>>>> to KV > > >>>>>>>>>>>> vs > > >>>>>>>>>>>>>>>>> window, etc -- but I just couldn't for the life of me > > >>>>>> think of > > >>>>>>>> the > > >>>>>>>>>>>>>>> right > > >>>>>>>>>>>>>>>>> term for rocks vs IM. We should 100% change to something > > >>>>>> like > > >>>>>>>>>>>>>>>> StoreImplSpec > > >>>>>>>>>>>>>>>>> for this kind of interface. > > >>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>> As for list-value store (for stream-stream Join) > > >>>>>>>>>>>>>>>>> Again, glad you mentioned this -- I forgot how the extra > > >>>>>>>>>>>> stream-stream > > >>>>>>>>>>>>>>>> join > > >>>>>>>>>>>>>>>>> store is not a "regular" KV Store but rather this special > > >>>>>>>>>>> list-value > > >>>>>>>>>>>>>>>> store. > > >>>>>>>>>>>>>>>>> If we proceed with something like the current approach, > > >>>>>> perhaps > > >>>>>>>>>>> that > > >>>>>>>>>>>>>>>> should > > >>>>>>>>>>>>>>>>> be a boolean (or enum) parameter in the KVConfig, similar > > >>>>>> to the > > >>>>>>>>>>>>>>>>> EmitStrategy? After all, the high-level goal of this KIP > > >>>>>> is to > > >>>>>>>> be > > >>>>>>>>>>>>>>> able to > > >>>>>>>>>>>>>>>>> fully customize all DSL state stores, and this is > > >>>>>> currently not > > >>>>>>>>>>>>>>> possible > > >>>>>>>>>>>>>>>>> due to KAFKA-14976 < > > >>>>>>>>>>>> https://issues.apache.org/jira/browse/KAFKA-14976 > > >>>>>>>>>>>>>>>> . > > >>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>> If we expect there to be further customizations like this > > >>>>>> going > > >>>>>>>>>>>>>>> forward, > > >>>>>>>>>>>>>>>>> perhaps we could instead have each of the three > > >>>>>> StoreConfig > > >>>>>>>> classes > > >>>>>>>>>>>>>>>> accept > > >>>>>>>>>>>>>>>>> a single enum parameter for the "sub-type" (or whatever > > >>>>>> you > > >>>>>>>> want to > > >>>>>>>>>>>>>>> call > > >>>>>>>>>>>>>>>>> it), which would encompass (and replace) things like the > > >>>>>>>>>>> EmitStrategy > > >>>>>>>>>>>>>>> as > > >>>>>>>>>>>>>>>>> well as the list-value type (we could define one enum for > > >>>>>> each > > >>>>>>>>>>> Config > > >>>>>>>>>>>>>>>> class > > >>>>>>>>>>>>>>>>> so there is no accidentally requesting a LIST_VALUE > > >>>>>> subtype on a > > >>>>>>>>>>>>>>>>> WindowStore). Thoughts? > > >>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>> Lastly, regarding 3.b: > > >>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>> I love that you brought this up because that is actually > > >>>>>> what I > > >>>>>>>>>>> first > > >>>>>>>>>>>>>>>>> proposed to Almog, ie introducing a param class to clean > > >>>>>> up the > > >>>>>>>>>>>>>>>>> StoreBuilder API, during our chat that led to this KIP. > > He > > >>>>>>>> pushed > > >>>>>>>>>>>>>>> back, > > >>>>>>>>>>>>>>>>> claiming (rightly so) that this change would be huge in > > >>>>>> scope > > >>>>>>>> for a > > >>>>>>>>>>>>>>>> purely > > >>>>>>>>>>>>>>>>> aesthetic/API change that doesn't add any functionality, > > >>>>>> and > > >>>>>>>> that > > >>>>>>>>>>> it > > >>>>>>>>>>>>>>>> makes > > >>>>>>>>>>>>>>>>> more sense to start with the DSL config since there is a > > >>>>>> clear > > >>>>>>>> gap > > >>>>>>>>>>> in > > >>>>>>>>>>>>>>>>> functionality there, particularly when it comes to custom > > >>>>>> state > > >>>>>>>>>>>> stores > > >>>>>>>>>>>>>>>>> (reasons 1 & 3 in the Motivation section). He did agree > > >>>>>> that the > > >>>>>>>>>>>> param > > >>>>>>>>>>>>>>>>> classes were a better API, which is why you see them in > > >>>>>> this > > >>>>>>>> KIP. > > >>>>>>>>>>> In > > >>>>>>>>>>>>>>>> other > > >>>>>>>>>>>>>>>>> words: I fully agree that we should apply this > > >>>>>> improvement to > > >>>>>>>> the > > >>>>>>>>>>>>>>>>> PAPI/StoreBuilder interface as well, but I think that's a > > >>>>>>>> distinct > > >>>>>>>>>>>>>>>> concept > > >>>>>>>>>>>>>>>>> for the time-being and should not block the DSL > > >>>>>> improvement. > > >>>>>>>>>>> Rather, > > >>>>>>>>>>>> I > > >>>>>>>>>>>>>>>>> consider this KIP as setting the stage for a followup KIP > > >>>>>> down > > >>>>>>>> the > > >>>>>>>>>>>>>>> line > > >>>>>>>>>>>>>>>> to > > >>>>>>>>>>>>>>>>> clean up the StoreBuilders and bring them in line with > > >>>>>> the new > > >>>>>>>>>>>>>>>> param/config > > >>>>>>>>>>>>>>>>> class approach. > > >>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>> That said, A) we should definitely make sure whatever we > > >>>>>>>> introduce > > >>>>>>>>>>>>>>> here > > >>>>>>>>>>>>>>>>> can be extended to the PAPI StoreBuilders in a natural > > >>>>>> way, and > > >>>>>>>> B) > > >>>>>>>>>>> I > > >>>>>>>>>>>>>>>> should > > >>>>>>>>>>>>>>>>> clarify that I personally would be happy to see this > > >>>>>> included in > > >>>>>>>>>>> the > > >>>>>>>>>>>>>>>>> current KIP, but as Almog's KIP it's up to him to decide > > >>>>>> whether > > >>>>>>>>>>> he's > > >>>>>>>>>>>>>>>>> comfortable expanding the scope like this. If you can > > >>>>>> convince > > >>>>>>>> him > > >>>>>>>>>>>>>>> where > > >>>>>>>>>>>>>>>> I > > >>>>>>>>>>>>>>>>> could not, more power to you! :P > > >>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>> On Sun, Jul 23, 2023 at 4:48 PM Sophie Blee-Goldman < > > >>>>>>>>>>>>>>>>> ableegold...@gmail.com> > > >>>>>>>>>>>>>>>>> wrote: > > >>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>> Matthias: > > >>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>> I'm not sure I agree with (or maybe don't follow) this > > >>>>>> take: > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> we need all kind of `StoreTypeSpec` implementations, > > >>>>>>>>>>>>>>>>>>> and it might also imply that we need follow up KIPs for > > >>>>>> new > > >>>>>>>>>>> feature > > >>>>>>>>>>>>>>>>>>> (like in-memory versioned store) that might not need a > > >>>>>> KIP > > >>>>>>>>>>>>>>> otherwise. > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>> I see this feature as being a nice add-on/convenience > > >>>>>> API for > > >>>>>>>> any > > >>>>>>>>>>>>>>> store > > >>>>>>>>>>>>>>>>>> types which have a full DSL implementation. I don't > > >>>>>> think it's > > >>>>>>>>>>>>>>>>> unreasonable > > >>>>>>>>>>>>>>>>>> to just say that this feature is only going to be > > >>>>>> available for > > >>>>>>>>>>>>>>> store > > >>>>>>>>>>>>>>>>> types > > >>>>>>>>>>>>>>>>>> that have KV, Window, and Session implementations. I > > >>>>>> can't > > >>>>>>>> think > > >>>>>>>>>>> of > > >>>>>>>>>>>>>>> any > > >>>>>>>>>>>>>>>>>> case besides versioned stores where this would force a > > >>>>>> KIP for > > >>>>>>>> a > > >>>>>>>>>>> new > > >>>>>>>>>>>>>>>>>> feature that would not otherwise have to go through a > > >>>>>> KIP, and > > >>>>>>>>>>> even > > >>>>>>>>>>>>>>> for > > >>>>>>>>>>>>>>>>>> versioned state stores, the only issue is that the KIP > > >>>>>> for that > > >>>>>>>>>>> was > > >>>>>>>>>>>>>>>>> already > > >>>>>>>>>>>>>>>>>> accepted. > > >>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>> However, I think I agree on your main point -- that > > >>>>>> things like > > >>>>>>>>>>>>>>>> "regular" > > >>>>>>>>>>>>>>>>>> vs timestamped vs versioned are/should be an > > >>>>>> implementation > > >>>>>>>> detail > > >>>>>>>>>>>>>>>> that's > > >>>>>>>>>>>>>>>>>> hidden from the user. As I noted previously, the current > > >>>>>> KIP > > >>>>>>>>>>>>>>> actually > > >>>>>>>>>>>>>>>>>> greatly improves the situation for timestamped stores, > > >>>>>> as this > > >>>>>>>>>>>>>>> would be > > >>>>>>>>>>>>>>>>>> handled completely transparently by the OOTB > > >>>>>> RocksDBStoreSpec. > > >>>>>>>> To > > >>>>>>>>>>>>>>> me, > > >>>>>>>>>>>>>>>>> this > > >>>>>>>>>>>>>>>>>> provides a very natural way to let the DSL operators > > >>>>>> using the > > >>>>>>>>>>>>>>> default > > >>>>>>>>>>>>>>>>>> store type/spec to specify which kind of store (eg > > >>>>>>>>>>>>>>>>>> versioned/timestamped/etc) it wants, and choose the > > >>>>>> correct > > >>>>>>>>>>>>>>> default. If > > >>>>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>> eventual intention is to have versioned state stores > > >>>>>> replace > > >>>>>>>>>>>>>>>> timestamped > > >>>>>>>>>>>>>>>>>> stores as the default in the DSL, then we can simply > > >>>>>> swap out > > >>>>>>>> the > > >>>>>>>>>>>>>>>>> versioned > > >>>>>>>>>>>>>>>>>> stores for the timestamped stores in the > > >>>>>> RocksDBStoreTypeSpec, > > >>>>>>>>>>> when > > >>>>>>>>>>>>>>>> that > > >>>>>>>>>>>>>>>>>> time comes. Until then, users who want to use the > > >>>>>> versioned > > >>>>>>>> store > > >>>>>>>>>>>>>>> will > > >>>>>>>>>>>>>>>>> have > > >>>>>>>>>>>>>>>>>> to do what they do today, which is individually override > > >>>>>>>> operators > > >>>>>>>>>>>>>>> via > > >>>>>>>>>>>>>>>>>> Materialized/StoreSuppliers. > > >>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>> All in all, it sounds like we should not offer a > > >>>>>> versioned > > >>>>>>>> store > > >>>>>>>>>>>>>>> type > > >>>>>>>>>>>>>>>>>> spec, as "versioned" is more akin to "timestamped" than > > >>>>>> to a > > >>>>>>>> true > > >>>>>>>>>>>>>>>>>> difference in underlying store implementation type (eg > > >>>>>> rocks vs > > >>>>>>>>>>>>>>>>> in-memory). > > >>>>>>>>>>>>>>>>>> W.r.t whether to deprecate the old config or introduce a > > >>>>>> new > > >>>>>>>>>>> CUSTOM > > >>>>>>>>>>>>>>>> enum > > >>>>>>>>>>>>>>>>>> type, either seems fine to me, and we can go with that > > >>>>>>>> alternative > > >>>>>>>>>>>>>>>>> instead. > > >>>>>>>>>>>>>>>>>> The only other con to this approach that I can think of, > > >>>>>> and > > >>>>>>>> I'm > > >>>>>>>>>>>>>>>> honestly > > >>>>>>>>>>>>>>>>>> not sure if this is something users would care about or > > >>>>>> only > > >>>>>>>> devs, > > >>>>>>>>>>>>>>> is > > >>>>>>>>>>>>>>>>> that > > >>>>>>>>>>>>>>>>>> the advantage to moving rocks and IM to the store type > > >>>>>> spec > > >>>>>>>>>>>>>>> interface > > >>>>>>>>>>>>>>>> is > > >>>>>>>>>>>>>>>>>> that it helps to keep the relevant logic encapsulated in > > >>>>>> one > > >>>>>>>> easy > > >>>>>>>>>>>>>>> place > > >>>>>>>>>>>>>>>>> you > > >>>>>>>>>>>>>>>>>> can quickly check to tell what kind of state store is > > >>>>>> used > > >>>>>>>> where. > > >>>>>>>>>>> In > > >>>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>> current code, I found it extremely annoying and > > >>>>>> difficult to > > >>>>>>>> track > > >>>>>>>>>>>>>>> down > > >>>>>>>>>>>>>>>>> all > > >>>>>>>>>>>>>>>>>> usages of the StoreType enum to see which actual rocksdb > > >>>>>> store > > >>>>>>>> was > > >>>>>>>>>>>>>>>> being > > >>>>>>>>>>>>>>>>>> used where (for example some stores using the > > >>>>>> TimeOrderedBuffer > > >>>>>>>>>>>>>>>> variants > > >>>>>>>>>>>>>>>>> in > > >>>>>>>>>>>>>>>>>> some special cases, or to understand whether the DSL was > > >>>>>>>>>>> defaulting > > >>>>>>>>>>>>>>> to > > >>>>>>>>>>>>>>>>>> plain, timestamped, or versioned stores for RocksDB vs > > >>>>>>>> InMemory -- > > >>>>>>>>>>>>>>> both > > >>>>>>>>>>>>>>>>> of > > >>>>>>>>>>>>>>>>>> which seem like they could be of interest to a user). > > >>>>>> This > > >>>>>>>> would > > >>>>>>>>>>> be > > >>>>>>>>>>>>>>>> much > > >>>>>>>>>>>>>>>>>> easier if everything was handled in one place, and you > > >>>>>> can > > >>>>>>>> just go > > >>>>>>>>>>>>>>> to > > >>>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>> (eg) RocksDBStoreTypeSpec and see what it's doing, or > > >>>>>> find > > >>>>>>>> usages > > >>>>>>>>>>> of > > >>>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>> methods to understand what stores are being handed to > > >>>>>> which DSL > > >>>>>>>>>>>>>>>>> operators. > > >>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>> I suppose we could still clean up the API and solve this > > >>>>>>>> problem > > >>>>>>>>>>> by > > >>>>>>>>>>>>>>>>> having > > >>>>>>>>>>>>>>>>>> the old (and new) config delegate to a StoreTypeSpec no > > >>>>>> matter > > >>>>>>>>>>> what, > > >>>>>>>>>>>>>>>> but > > >>>>>>>>>>>>>>>>>> make RocksDBStoreTypeSpec and InMemoryStoreTypeSpec > > >>>>>> internal > > >>>>>>>>>>> classes > > >>>>>>>>>>>>>>>> that > > >>>>>>>>>>>>>>>>>> are simply implementation details of the ROCKSDB vs > > >>>>>> IN_MEMORY > > >>>>>>>>>>> enums. > > >>>>>>>>>>>>>>>>> WDYT? > > >>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>> On Sun, Jul 23, 2023 at 11:14 AM Guozhang Wang < > > >>>>>>>>>>>>>>>>> guozhang.wang...@gmail.com> > > >>>>>>>>>>>>>>>>>> wrote: > > >>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> Thanks everyone for the great discussions so far! I > > >>>>>> first saw > > >>>>>>>> the > > >>>>>>>>>>>>>>> JIRA > > >>>>>>>>>>>>>>>>>>> and left some quick thoughts without being aware of the > > >>>>>>>>>>>>>>>>>>> already-written KIP (kudos to Almog, very great one) > > >>>>>> and the > > >>>>>>>>>>>>>>> DISCUSS > > >>>>>>>>>>>>>>>>>>> thread here. And I happily find some of my initial > > >>>>>> thoughts > > >>>>>>>> align > > >>>>>>>>>>>>>>> with > > >>>>>>>>>>>>>>>>>>> the KIP already :) > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> Would like to add a bit more of my 2c after reading > > >>>>>> through > > >>>>>>>> the > > >>>>>>>>>>> KIP > > >>>>>>>>>>>>>>>>>>> and the thread here: > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> 1. On the high level, I'm in favor of pushing this KIP > > >>>>>> through > > >>>>>>>>>>>>>>> without > > >>>>>>>>>>>>>>>>>>> waiting on the other gaps to be closed. In my back > > >>>>>> pocket's > > >>>>>>>>>>>>>>>>>>> "dependency graph" of Kafka Streams roadmap of large > > >>>>>> changes > > >>>>>>>> or > > >>>>>>>>>>>>>>>>>>> feature gaps, the edges of dependencies are defined > > >>>>>> based on > > >>>>>>>> my > > >>>>>>>>>>>>>>>>>>> understanding of whether doing one first would largely > > >>>>>>>>>>> complicate / > > >>>>>>>>>>>>>>>>>>> negate the effort of the other but not vice versa, in > > >>>>>> which > > >>>>>>>> case > > >>>>>>>>>>> we > > >>>>>>>>>>>>>>>>>>> should consider getting the other done first. In this > > >>>>>> case, I > > >>>>>>>>>>> feel > > >>>>>>>>>>>>>>>>>>> such a dependency is not strong enough, so encouraging > > >>>>>> the KIP > > >>>>>>>>>>>>>>>>>>> contributor to finish what he/she would love to do to > > >>>>>> close > > >>>>>>>> some > > >>>>>>>>>>>>>>> gaps > > >>>>>>>>>>>>>>>>>>> early would be higher priorities. I did not see by just > > >>>>>> doing > > >>>>>>>>>>> this > > >>>>>>>>>>>>>>> we > > >>>>>>>>>>>>>>>>>>> could end up in a worse intermediate stage yet, but I > > >>>>>> could be > > >>>>>>>>>>>>>>>>>>> corrected. > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> 2. Regarding the store types --- gain here I'd like to > > >>>>>> just > > >>>>>>>>>>> clarify > > >>>>>>>>>>>>>>>>>>> the terms a bit since in the past it has some > > >>>>>> confusions: we > > >>>>>>>> used > > >>>>>>>>>>>>>>>>>>> "impl types" (in hindsight it may not be a good name) > > >>>>>> for > > >>>>>>>>>>> rocksdb / > > >>>>>>>>>>>>>>>>>>> memory / custom, and we used "store types" for kv / > > >>>>>> windowed / > > >>>>>>>>>>>>>>>>>>> sessioned etc, as I said in the JIRA I think the > > current > > >>>>>>>> proposal > > >>>>>>>>>>>>>>> also > > >>>>>>>>>>>>>>>>>>> have a good side effect as quality bar to really > > >>>>>> enforce us > > >>>>>>>> think > > >>>>>>>>>>>>>>>>>>> twice when trying to add more store types in the future > > >>>>>> as it > > >>>>>>>>>>> will > > >>>>>>>>>>>>>>>>>>> impact API instantiations. In the ideal world, I would > > >>>>>>>> consider: > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> * We have (timestamped) kv store, versioned kv store, > > >>>>>> window > > >>>>>>>>>>> store, > > >>>>>>>>>>>>>>>>>>> session store as first-class DSL store types. Some DSL > > >>>>>>>> operators > > >>>>>>>>>>>>>>> could > > >>>>>>>>>>>>>>>>>>> accept multiple store types (e.g. versioned and non > > >>>>>> versioned > > >>>>>>>>>>>>>>>>>>> kv-store) for semantics / efficiency trade-offs. But I > > >>>>>> think > > >>>>>>>> we > > >>>>>>>>>>>>>>> would > > >>>>>>>>>>>>>>>>>>> remove un-timestamped kv stores eventually since that > > >>>>>>>> efficiency > > >>>>>>>>>>>>>>>>>>> trade-off is so minimal compared to its usage > > >>>>>> limitations. > > >>>>>>>>>>>>>>>>>>> * As for list-value store (for stream-stream Join), > > >>>>>>>>>>>>>>> memory-lru-cache > > >>>>>>>>>>>>>>>>>>> (for PAPI use only), memory-time-ordered-buffer (for > > >>>>>>>>>>> suppression), > > >>>>>>>>>>>>>>>>>>> they would not be exposed as DSL first-class store > > >>>>>> types in > > >>>>>>>> the > > >>>>>>>>>>>>>>>>>>> future. Instead, they would be treated as internal used > > >>>>>> stores > > >>>>>>>>>>>>>>> (e.g. > > >>>>>>>>>>>>>>>>>>> list-value store is built on key-value store with > > >>>>>> specialized > > >>>>>>>>>>> serde > > >>>>>>>>>>>>>>>>>>> and putInternal), or continue to be just convenient > > >>>>>> OOTB PAPI > > >>>>>>>>>>> used > > >>>>>>>>>>>>>>>>>>> stores only. > > >>>>>>>>>>>>>>>>>>> * As we move on, we will continue to be very, very > > >>>>>> strict on > > >>>>>>>> what > > >>>>>>>>>>>>>>>>>>> would be added as DSL store types (and hence requires > > >>>>>> changes > > >>>>>>>> to > > >>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>> proposed APIs), what to be added as convenient OOTB > > >>>>>> PAPI store > > >>>>>>>>>>>>>>> impls > > >>>>>>>>>>>>>>>>>>> only, what to be added as internal used store types > > that > > >>>>>>>> should > > >>>>>>>>>>>>>>> not be > > >>>>>>>>>>>>>>>>>>> exposed to users nor customizable at all. > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> 3. Some more detailed thoughts below: > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> 3.a) I originally also think that we can extend the > > >>>>>> existing > > >>>>>>>>>>>>>>> config, > > >>>>>>>>>>>>>>>>>>> rather than replacing it. The difference was that I was > > >>>>>>>> thinking > > >>>>>>>>>>>>>>> that > > >>>>>>>>>>>>>>>>>>> order-wise, the runtime would look at the API first, > > >>>>>> and then > > >>>>>>>> the > > >>>>>>>>>>>>>>>>>>> config, whereas in your rejected alternative it was > > >>>>>> looking at > > >>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>> config first, and then the API --- that I think is a > > >>>>>> minor > > >>>>>>>> thing > > >>>>>>>>>>>>>>> and > > >>>>>>>>>>>>>>>>>>> either is fine. I'm in agreement that having two > > configs > > >>>>>>>> would be > > >>>>>>>>>>>>>>> more > > >>>>>>>>>>>>>>>>>>> confusing to users to learn about their precedence > > >>>>>> rather than > > >>>>>>>>>>>>>>>>>>> helpful, but if we keep both a config and a public API, > > >>>>>> then > > >>>>>>>> the > > >>>>>>>>>>>>>>>>>>> precedence ordering would not be so confusing as long > > >>>>>> as we > > >>>>>>>> state > > >>>>>>>>>>>>>>> them > > >>>>>>>>>>>>>>>>>>> clearly. For example: > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> * We have DefaultStoreTypeSpec OOTB, in that impl we > > >>>>>> look at > > >>>>>>>> the > > >>>>>>>>>>>>>>>>>>> config only, and would only expect either ROCKS or > > >>>>>> MEMORY, and > > >>>>>>>>>>>>>>> return > > >>>>>>>>>>>>>>>>>>> corresponding OOTB store impls; if any other values > > >>>>>>>> configured, > > >>>>>>>>>>> we > > >>>>>>>>>>>>>>>>>>> error out. > > >>>>>>>>>>>>>>>>>>> * Users extend that by having MyStoreTypeSpec, in which > > >>>>>> they > > >>>>>>>>>>> could > > >>>>>>>>>>>>>>> do > > >>>>>>>>>>>>>>>>>>> arbituray things without respecting the config at all, > > >>>>>> but our > > >>>>>>>>>>>>>>>>>>> recommended pattern in docs would still say "look into > > >>>>>> the > > >>>>>>>>>>> config, > > >>>>>>>>>>>>>>> if > > >>>>>>>>>>>>>>>>>>> it is ROCKS or MEMORY just return fall back to > > >>>>>>>>>>>>>>> DefaultStoreTypeSepc; > > >>>>>>>>>>>>>>>>>>> otherwise if it's some String you recognize, then > > >>>>>> return your > > >>>>>>>>>>>>>>>>>>> customized store based on the string value, otherwise > > >>>>>> error > > >>>>>>>> out". > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> 3.b) About the struct-like Params classes, I like the > > >>>>>> idea a > > >>>>>>>> lot > > >>>>>>>>>>>>>>> and > > >>>>>>>>>>>>>>>>>>> wished we would pursue this in the first place, but if > > >>>>>> we > > >>>>>>>> only do > > >>>>>>>>>>>>>>> this > > >>>>>>>>>>>>>>>>>>> in Spec it would leave some inconsistencies with the > > >>>>>>>>>>> StoreBuilders > > >>>>>>>>>>>>>>>>>>> though arguably the latter is only for PAPI. I'm > > >>>>>> wondering if > > >>>>>>>> we > > >>>>>>>>>>>>>>>>>>> should consider including the changes in StoreBuilders > > >>>>>> (e.g. > > >>>>>>>>>>>>>>>>>>> WindowStoreBuilder(WindowSupplierParams)), and if yes, > > >>>>>> maybe > > >>>>>>>> we > > >>>>>>>>>>>>>>> should > > >>>>>>>>>>>>>>>>>>> also consider renaming that e.g. `WindowSupplierParams` > > >>>>>> to > > >>>>>>>>>>>>>>>>>>> `WindowStoreSpecParams` too? For this one I only have a > > >>>>>> "weak > > >>>>>>>>>>>>>>> feeling" > > >>>>>>>>>>>>>>>>>>> so I can be convinced otherwise :P > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> Thanks, > > >>>>>>>>>>>>>>>>>>> Guozhang > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> On Sun, Jul 23, 2023 at 9:52 AM Matthias J. Sax < > > >>>>>>>>>>> mj...@apache.org> > > >>>>>>>>>>>>>>>>> wrote: > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> Thanks for all the input. My intention was not to > > >>>>>> block the > > >>>>>>>> KIP, > > >>>>>>>>>>>>>>> but > > >>>>>>>>>>>>>>>>>>>> just to take a step back and try get a holistic > > >>>>>> picture and > > >>>>>>>>>>>>>>>>> discussion, > > >>>>>>>>>>>>>>>>>>>> to explore if there are good/viable alternative > > >>>>>> designs. As > > >>>>>>>> said > > >>>>>>>>>>>>>>>>>>>> originally, I really like to close this gap, and was > > >>>>>> always > > >>>>>>>>>>> aware > > >>>>>>>>>>>>>>>> that > > >>>>>>>>>>>>>>>>>>>> the current config is not flexible enough. > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> I guess, my "concern" is that the KIP does increase > > >>>>>> the API > > >>>>>>>>>>>>>>> surface > > >>>>>>>>>>>>>>>>> area > > >>>>>>>>>>>>>>>>>>>> significantly, as we need all kind of `StoreTypeSpec` > > >>>>>>>>>>>>>>>> implementations, > > >>>>>>>>>>>>>>>>>>>> and it might also imply that we need follow up KIPs > > >>>>>> for new > > >>>>>>>>>>>>>>> feature > > >>>>>>>>>>>>>>>>>>>> (like in-memory versioned store) that might not need a > > >>>>>> KIP > > >>>>>>>>>>>>>>>> otherwise. > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> The second question is if it might make the already > > >>>>>> "patchy" > > >>>>>>>>>>>>>>>> situation > > >>>>>>>>>>>>>>>>>>>> with regard to customization worse. > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> We did de-scope the original KIP-591 for this reason, > > >>>>>> and > > >>>>>>>> given > > >>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>> new > > >>>>>>>>>>>>>>>>>>>> situation of the DSL, it seems that it actually got > > >>>>>> worse > > >>>>>>>>>>>>>>> compared > > >>>>>>>>>>>>>>>> to > > >>>>>>>>>>>>>>>>>>>> back in the days. > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> Lastly, I hope to make the new versioned stores the > > >>>>>> default > > >>>>>>>> in > > >>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>> DSL > > >>>>>>>>>>>>>>>>>>>> and we did not do it in the previous KIP due to > > >>>>>> backward > > >>>>>>>>>>>>>>>> compatibility > > >>>>>>>>>>>>>>>>>>>> issues. Thus, from a DSL point of view, I believe > > there > > >>>>>>>> should > > >>>>>>>>>>> be > > >>>>>>>>>>>>>>>> only > > >>>>>>>>>>>>>>>>>>>> "RocksDB", "InMemory", and "Custom" in an ideal world. > > >>>>>>>>>>>>>>> Introducing > > >>>>>>>>>>>>>>>> (I > > >>>>>>>>>>>>>>>>> am > > >>>>>>>>>>>>>>>>>>>> exaggerating to highlight my point) "KvRocksDbSpec", > > >>>>>>>>>>>>>>>>>>>> "TimestampeKvRocksDbSpec", "VersionedRocksDbSpec", > > >>>>>> plus the > > >>>>>>>>>>>>>>>>>>>> corresponding in-memory specs seems to head into the > > >>>>>> opposite > > >>>>>>>>>>>>>>>>> direction. > > >>>>>>>>>>>>>>>>>>>> -- My goal is to give users a handle of the _physical_ > > >>>>>> store > > >>>>>>>>>>>>>>>> (RocksDB > > >>>>>>>>>>>>>>>>> vs > > >>>>>>>>>>>>>>>>>>>> InMemory vs Custom) but not the _logical_ stores > > >>>>>> (plain kv, > > >>>>>>>>>>>>>>> ts-kv, > > >>>>>>>>>>>>>>>>>>>> versioned) which is "dictated" by the DSL itself and > > >>>>>> should > > >>>>>>>> not > > >>>>>>>>>>>>>>> be > > >>>>>>>>>>>>>>>>>>>> customizable (we are just in a weird intermediate > > >>>>>> situation > > >>>>>>>> that > > >>>>>>>>>>>>>>> we > > >>>>>>>>>>>>>>>>> need > > >>>>>>>>>>>>>>>>>>>> to clean up, but not "lean into" IMHO). > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> Thus, I am also not sure if adding > > >>>>>> "VersionedRocksDbSpec" > > >>>>>>>> would > > >>>>>>>>>>>>>>> be > > >>>>>>>>>>>>>>>>> ideal > > >>>>>>>>>>>>>>>>>>>> (also, given that it only changes a single store, but > > >>>>>> not the > > >>>>>>>>>>> two > > >>>>>>>>>>>>>>>>>>>> windowed stores)? > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> Furthermore, I actually hope that we could use the new > > >>>>>>>> versioned > > >>>>>>>>>>>>>>>> store > > >>>>>>>>>>>>>>>>>>>> to replace the window- and sessions- stores, and thus > > >>>>>> to > > >>>>>>>>>>> decrease > > >>>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>>> number of required store types. > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> Admittedly, I am talking a lot about a potential > > >>>>>> future, but > > >>>>>>>> the > > >>>>>>>>>>>>>>>> goal > > >>>>>>>>>>>>>>>>> is > > >>>>>>>>>>>>>>>>>>>> only to explore opportunities to not get into "worse" > > >>>>>>>>>>>>>>> intermediate > > >>>>>>>>>>>>>>>>>>>> state, that will require a huge deprecation surface > > >>>>>> area > > >>>>>>>> later > > >>>>>>>>>>>>>>> on. > > >>>>>>>>>>>>>>>> Of > > >>>>>>>>>>>>>>>>>>>> course, if there is no better way, and my concerns are > > >>>>>> not > > >>>>>>>>>>>>>>> shared, I > > >>>>>>>>>>>>>>>>> am > > >>>>>>>>>>>>>>>>>>>> ok to move forward with the KIP. > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> Bottom line: I would personally prefer to keep the > > >>>>>> current > > >>>>>>>>>>> config > > >>>>>>>>>>>>>>>> and > > >>>>>>>>>>>>>>>>>>>> add a `Custom` option to it, plus adding one new > > >>>>>> config that > > >>>>>>>>>>>>>>> allows > > >>>>>>>>>>>>>>>>>>>> people to set their custom `StoreTypeSpec` class. -- I > > >>>>>> would > > >>>>>>>> not > > >>>>>>>>>>>>>>>> add a > > >>>>>>>>>>>>>>>>>>>> built-in spec for versioned stores at this point (or > > >>>>>> any > > >>>>>>>> other > > >>>>>>>>>>>>>>>>> built-in > > >>>>>>>>>>>>>>>>>>>> `StorytypeSpec` implementations). I guess, users could > > >>>>>> write > > >>>>>>>> a > > >>>>>>>>>>>>>>>> custom > > >>>>>>>>>>>>>>>>>>>> spec if they want to enable versioned store across the > > >>>>>> board > > >>>>>>>> for > > >>>>>>>>>>>>>>> now > > >>>>>>>>>>>>>>>>>>>> (until we make them the default anyway)? > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> Hope my train of thoughts is halfway reasonable and > > not > > >>>>>>>> totally > > >>>>>>>>>>>>>>> off > > >>>>>>>>>>>>>>>>>>> track? > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> -Matthias > > >>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>> On 7/21/23 15:27, Sophie Blee-Goldman wrote: > > >>>>>>>>>>>>>>>>>>>>> I agree with everything Almog said above, and will > > >>>>>> just add > > >>>>>>>> on > > >>>>>>>>>>>>>>> to > > >>>>>>>>>>>>>>>>> two > > >>>>>>>>>>>>>>>>>>>>> points: > > >>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>> 1. Regarding whether to block this KIP on the > > >>>>>> completion of > > >>>>>>>>>>>>>>> any or > > >>>>>>>>>>>>>>>>> all > > >>>>>>>>>>>>>>>>>>>>> future implementations of in-memory version stores > > (or > > >>>>>>>> persist > > >>>>>>>>>>>>>>>>>>> suppression > > >>>>>>>>>>>>>>>>>>>>> buffers), I feel that would be unfair to this feature > > >>>>>> which > > >>>>>>>> is > > >>>>>>>>>>>>>>>>>>> completely > > >>>>>>>>>>>>>>>>>>>>> unrelated to the semantic improvements offered by > > >>>>>> versioned > > >>>>>>>>>>>>>>> state > > >>>>>>>>>>>>>>>>>>> stores. > > >>>>>>>>>>>>>>>>>>>>> It seems like the responsibility of those driving the > > >>>>>>>> versioned > > >>>>>>>>>>>>>>>>> state > > >>>>>>>>>>>>>>>>>>>>> stores feature, not Almog/this KIP, to make sure that > > >>>>>> those > > >>>>>>>>>>>>>>> bases > > >>>>>>>>>>>>>>>>> are > > >>>>>>>>>>>>>>>>>>>>> covered. Further, if anything, this KIP will help > > >>>>>> with the > > >>>>>>>>>>>>>>> massive > > >>>>>>>>>>>>>>>>>>>>> proliferation of StoreSuppliers on the Stores factory > > >>>>>> class, > > >>>>>>>>>>>>>>> and > > >>>>>>>>>>>>>>>>>>> provide > > >>>>>>>>>>>>>>>>>>>>> users with a much easier way to leverage the > > versioned > > >>>>>>>> stores > > >>>>>>>>>>>>>>>>> without > > >>>>>>>>>>>>>>>>>>>>> having to muck around directly with the > > >>>>>> StoreSuppliers. > > >>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>> I also thought about it a bit, and really like > > Almog's > > >>>>>>>>>>>>>>> suggestion > > >>>>>>>>>>>>>>>> to > > >>>>>>>>>>>>>>>>>>>>> introduce an additional StoreSpec for the Versioned > > >>>>>> state > > >>>>>>>>>>>>>>> stores. > > >>>>>>>>>>>>>>>>>>> Obviously > > >>>>>>>>>>>>>>>>>>>>> we can add the RocksDB one to this KIP now, and then > > >>>>>> as he > > >>>>>>>>>>>>>>>>> mentioned, > > >>>>>>>>>>>>>>>>>>>>> there's an easy way to get users onto the > > >>>>>>>> IMVersionedStateStore > > >>>>>>>>>>>>>>>>> types > > >>>>>>>>>>>>>>>>>>> once > > >>>>>>>>>>>>>>>>>>>>> they are completed. > > >>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>> Lastly, on this note, I want to point out how > > >>>>>> smoothly this > > >>>>>>>>>>>>>>> solved > > >>>>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>>>> issue of timestamped stores, which are intended to be > > >>>>>> the > > >>>>>>>> DSL > > >>>>>>>>>>>>>>>>> default > > >>>>>>>>>>>>>>>>>>> but > > >>>>>>>>>>>>>>>>>>>>> are only a special case for RocksDB. Right now it can > > >>>>>> be > > >>>>>>>>>>>>>>> confusing > > >>>>>>>>>>>>>>>>>>> for a > > >>>>>>>>>>>>>>>>>>>>> user scrolling through the endless Stores class and > > >>>>>> seeing a > > >>>>>>>>>>>>>>>>>>> timestamped > > >>>>>>>>>>>>>>>>>>>>> version of the persistent but not in-memory stores. > > >>>>>> One > > >>>>>>>> could > > >>>>>>>>>>>>>>>> easily > > >>>>>>>>>>>>>>>>>>> assume > > >>>>>>>>>>>>>>>>>>>>> there was no timestamped option for IM stores and > > >>>>>> that this > > >>>>>>>>>>>>>>>> feature > > >>>>>>>>>>>>>>>>>>> was > > >>>>>>>>>>>>>>>>>>>>> incomplete, if they weren't acutely aware of the > > >>>>>> internal > > >>>>>>>>>>>>>>>>>>> implementation > > >>>>>>>>>>>>>>>>>>>>> details (namely that it's only required for RocksDB > > >>>>>> for > > >>>>>>>>>>>>>>>>> compatibility > > >>>>>>>>>>>>>>>>>>>>> reasons). However, with this KIP, all that is handled > > >>>>>>>>>>>>>>> completely > > >>>>>>>>>>>>>>>>>>>>> transparently to the user, and we the devs, who *are* > > >>>>>> aware > > >>>>>>>> of > > >>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>> internal > > >>>>>>>>>>>>>>>>>>>>> implementation details, are now appropriately the > > ones > > >>>>>>>>>>>>>>> responsible > > >>>>>>>>>>>>>>>>> for > > >>>>>>>>>>>>>>>>>>>>> handing the correct store type to a particular > > >>>>>> operator. > > >>>>>>>> While > > >>>>>>>>>>>>>>>>>>> versioned > > >>>>>>>>>>>>>>>>>>>>> state stores may not be completely comparable, > > >>>>>> depending on > > >>>>>>>>>>>>>>>> whether > > >>>>>>>>>>>>>>>>>>> we want > > >>>>>>>>>>>>>>>>>>>>> users to remain able to easily choose between using > > >>>>>> them or > > >>>>>>>> not > > >>>>>>>>>>>>>>>> (vs > > >>>>>>>>>>>>>>>>>>>>> timestamped which should be used by all), I still > > >>>>>> feel this > > >>>>>>>> KIP > > >>>>>>>>>>>>>>>> is a > > >>>>>>>>>>>>>>>>>>> great > > >>>>>>>>>>>>>>>>>>>>> step in the right direction that not only should not > > >>>>>> be > > >>>>>>>>>>>>>>> blocked on > > >>>>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>>>> completion of the IM implementations, but in fact > > >>>>>> should > > >>>>>>>>>>>>>>>>> specifically > > >>>>>>>>>>>>>>>>>>> be > > >>>>>>>>>>>>>>>>>>>>> done first as it enables an easier way to utilize > > >>>>>> those IM > > >>>>>>>>>>>>>>>> versioned > > >>>>>>>>>>>>>>>>>>>>> stores. Just my 2 cents :) > > >>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>> 2. The idea to expand the existing the config with a > > >>>>>> CUSTOM > > >>>>>>>>>>>>>>> enum > > >>>>>>>>>>>>>>>>>>> without > > >>>>>>>>>>>>>>>>>>>>> introducing another config to specify the CUSTOM > > >>>>>> store spec > > >>>>>>>>>>>>>>> does > > >>>>>>>>>>>>>>>> not > > >>>>>>>>>>>>>>>>>>> seem > > >>>>>>>>>>>>>>>>>>>>> appropriate, or even possible (for the reasons Almog > > >>>>>>>> mentioned > > >>>>>>>>>>>>>>>>> above > > >>>>>>>>>>>>>>>>>>> about > > >>>>>>>>>>>>>>>>>>>>> config types, though perhaps there is a way I'm not > > >>>>>>>> seeing). I > > >>>>>>>>>>>>>>> do > > >>>>>>>>>>>>>>>>> not > > >>>>>>>>>>>>>>>>>>> buy > > >>>>>>>>>>>>>>>>>>>>> the argument that we should optimize the API to make > > >>>>>> it easy > > >>>>>>>>>>>>>>> for > > >>>>>>>>>>>>>>>>>>> users who > > >>>>>>>>>>>>>>>>>>>>> just want to switch to all in-memory stores, as I > > >>>>>> truly > > >>>>>>>> believe > > >>>>>>>>>>>>>>>> this > > >>>>>>>>>>>>>>>>>>> is a > > >>>>>>>>>>>>>>>>>>>>> very small fraction of the potential userbase of this > > >>>>>>>> feature > > >>>>>>>>>>>>>>>>> (anyone > > >>>>>>>>>>>>>>>>>>> who's > > >>>>>>>>>>>>>>>>>>>>> actually using this should please chime in!). It > > >>>>>> seems very > > >>>>>>>>>>>>>>> likely > > >>>>>>>>>>>>>>>>>>> that the > > >>>>>>>>>>>>>>>>>>>>> majority of users of this feature are actually those > > >>>>>> with > > >>>>>>>>>>>>>>> custom > > >>>>>>>>>>>>>>>>> state > > >>>>>>>>>>>>>>>>>>>>> stores, as to my knowledge, this has been the case > > >>>>>> any/every > > >>>>>>>>>>>>>>> time > > >>>>>>>>>>>>>>>>> this > > >>>>>>>>>>>>>>>>>>>>> feature was requested by users. > > >>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>> That said, while I don't see any way to get around > > >>>>>>>> introducing > > >>>>>>>>>>>>>>> a > > >>>>>>>>>>>>>>>> new > > >>>>>>>>>>>>>>>>>>>>> config, I don't personally have a preference w.r.t > > >>>>>> whether > > >>>>>>>> to > > >>>>>>>>>>>>>>> keep > > >>>>>>>>>>>>>>>>>>> around > > >>>>>>>>>>>>>>>>>>>>> the old config or deprecate it. I simply don't get > > the > > >>>>>>>>>>>>>>> impression > > >>>>>>>>>>>>>>>> it > > >>>>>>>>>>>>>>>>>>> is > > >>>>>>>>>>>>>>>>>>>>> very heavily used as it stands today, while it only > > >>>>>> works > > >>>>>>>> for > > >>>>>>>>>>>>>>>> those > > >>>>>>>>>>>>>>>>>>> who > > >>>>>>>>>>>>>>>>>>>>> want all in-memory stores. Again, input from actual > > >>>>>> users > > >>>>>>>>>>>>>>> would be > > >>>>>>>>>>>>>>>>>>> very > > >>>>>>>>>>>>>>>>>>>>> valuable here. In the absence of that data, I will > > >>>>>> just > > >>>>>>>> point > > >>>>>>>>>>>>>>> to > > >>>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>> fact > > >>>>>>>>>>>>>>>>>>>>> that this KIP was proposed by a Streams dev (you :P), > > >>>>>>>>>>>>>>> abandoned, > > >>>>>>>>>>>>>>>>>>> picked up > > >>>>>>>>>>>>>>>>>>>>> by another Streams dev, and finally implemented > > >>>>>> without ever > > >>>>>>>>>>>>>>>> hearing > > >>>>>>>>>>>>>>>>>>> from a > > >>>>>>>>>>>>>>>>>>>>> user that they would find this useful. This is not to > > >>>>>>>> disparage > > >>>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>>>> original KIP, but just to say again, as I stated back > > >>>>>> then, > > >>>>>>>> it > > >>>>>>>>>>>>>>>>> seemed > > >>>>>>>>>>>>>>>>>>> like > > >>>>>>>>>>>>>>>>>>>>> a major opportunity loss to leave out custom state > > >>>>>> stores > > >>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>> Cheers, > > >>>>>>>>>>>>>>>>>>>>> Sophie > > >>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>> On Fri, Jul 21, 2023 at 1:52 PM Almog Gavra < > > >>>>>>>>>>>>>>>> almog.ga...@gmail.com> > > >>>>>>>>>>>>>>>>>>> wrote: > > >>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>> Thanks for all the feedback folk! Responses inline. > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> Basically, I'm suggesting two things: first, call > > >>>>>> out in > > >>>>>>>> some > > >>>>>>>>>>>>>>>> way > > >>>>>>>>>>>>>>>>>>>>>> (perhaps the StoreTypeSpec javadocs) that each > > >>>>>>>> StoreTypeSpec > > >>>>>>>>>>>>>>> is > > >>>>>>>>>>>>>>>>>>> considered > > >>>>>>>>>>>>>>>>>>>>>> a public contract in itself and should outline any > > >>>>>> semantic > > >>>>>>>>>>>>>>>>>>> guarantees it > > >>>>>>>>>>>>>>>>>>>>>> does, or does not, make. Second, we should add a > > >>>>>> note on > > >>>>>>>>>>>>>>> ordering > > >>>>>>>>>>>>>>>>>>>>>> guarantees in the two OOTB specs: for RocksDB we > > >>>>>> assert > > >>>>>>>> that > > >>>>>>>>>>>>>>>> range > > >>>>>>>>>>>>>>>>>>> queries > > >>>>>>>>>>>>>>>>>>>>>> will honor serialized byte ordering, whereas the > > >>>>>> InMemory > > >>>>>>>>>>>>>>> flavor > > >>>>>>>>>>>>>>>>>>> gives no > > >>>>>>>>>>>>>>>>>>>>>> ordering guarantee whatsoever at this time. > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>> That makes sense to me Sophie! I'll make the changes > > >>>>>> to the > > >>>>>>>>>>>>>>> KIP. > > >>>>>>>>>>>>>>>>> And > > >>>>>>>>>>>>>>>>>>> @Colt, > > >>>>>>>>>>>>>>>>>>>>>> yes I believe that would be the new javadoc for the > > >>>>>> generic > > >>>>>>>>>>>>>>>>>>>>>> ReadOnlyKeyValueStore. > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> However, I am wondering if we should close others > > >>>>>> gaps > > >>>>>>>> first? > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>> @Matthias, thanks for the review and thoughts! I > > >>>>>> think we > > >>>>>>>>>>>>>>> should > > >>>>>>>>>>>>>>>>>>> separate > > >>>>>>>>>>>>>>>>>>>>>> closing other gaps in the product from providing > > >>>>>> this as > > >>>>>>>>>>>>>>> useful > > >>>>>>>>>>>>>>>>>>>>>> functionality to avoid feature creep so long as the > > >>>>>> API > > >>>>>>>>>>>>>>> proposed > > >>>>>>>>>>>>>>>>>>> here will > > >>>>>>>>>>>>>>>>>>>>>> be suitable for when we want to close those > > >>>>>> implementation > > >>>>>>>>>>>>>>> gaps! > > >>>>>>>>>>>>>>>> My > > >>>>>>>>>>>>>>>>>>> general > > >>>>>>>>>>>>>>>>>>>>>> proposal is that for things that are not > > customizable > > >>>>>>>> today by > > >>>>>>>>>>>>>>>>>>>>>> default.dsl.store they remain not customizable after > > >>>>>> this > > >>>>>>>> KIP. > > >>>>>>>>>>>>>>>> The > > >>>>>>>>>>>>>>>>>>> good > > >>>>>>>>>>>>>>>>>>>>>> news is, however, that there's no reason why this > > >>>>>> cannot be > > >>>>>>>>>>>>>>>>> extended > > >>>>>>>>>>>>>>>>>>> to > > >>>>>>>>>>>>>>>>>>>>>> cover those in the future if we want to - see > > >>>>>> specifics > > >>>>>>>> below. > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>> Comments on the specifics below > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> In particular, this holds for the new > > >>>>>> versioned-store ... > > >>>>>>>>>>>>>>> Should > > >>>>>>>>>>>>>>>>>>>>>> versioned stores also be covered by the KIP > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>> Is there a reason why we can't introduce a > > >>>>>>>>>>>>>>>>>>> VersionedRocksDBStoreTypeSpec > > >>>>>>>>>>>>>>>>>>>>>> and if we ever support an in-memory an equivalent > > >>>>>>>>>>>>>>>>>>>>>> VersionedInMemoryRocksDBStoreTypeSpec? If so, then > > >>>>>> there > > >>>>>>>> would > > >>>>>>>>>>>>>>>> not > > >>>>>>>>>>>>>>>>>>> need to > > >>>>>>>>>>>>>>>>>>>>>> be any additional changes to the API proposed in > > >>>>>> this KIP. > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> For `suppress()` it's actually other way around we > > >>>>>> only > > >>>>>>>> have > > >>>>>>>>>>>>>>> an > > >>>>>>>>>>>>>>>>>>> in-memory > > >>>>>>>>>>>>>>>>>>>>>> implementation. Do you aim to allow custom stores > > for > > >>>>>>>>>>>>>>>> `suppress()`, > > >>>>>>>>>>>>>>>>>>> too? > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>> We have three options here: > > >>>>>>>>>>>>>>>>>>>>>> 1) we can decide to maintain existing behavior and > > >>>>>> use the > > >>>>>>>>>>>>>>>>> in-memory > > >>>>>>>>>>>>>>>>>>>>>> implementation for all stores (not even going > > >>>>>> through the > > >>>>>>>> API > > >>>>>>>>>>>>>>> at > > >>>>>>>>>>>>>>>>> all) > > >>>>>>>>>>>>>>>>>>>>>> 2a) we can introduce a new parameter to the > > >>>>>> KeyValueParams > > >>>>>>>>>>>>>>> class > > >>>>>>>>>>>>>>>>>>> (boolean > > >>>>>>>>>>>>>>>>>>>>>> isTimeOrderedBuffer or something like that) and > > >>>>>> return an > > >>>>>>>>>>>>>>>> in-memory > > >>>>>>>>>>>>>>>>>>> store > > >>>>>>>>>>>>>>>>>>>>>> in the implementation of RocksDBStoreTypeSpec (this > > >>>>>>>> maintains > > >>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>> existing > > >>>>>>>>>>>>>>>>>>>>>> behavior, and would allow us in the future to make > > >>>>>> the > > >>>>>>>> change > > >>>>>>>>>>>>>>> to > > >>>>>>>>>>>>>>>>>>> return a > > >>>>>>>>>>>>>>>>>>>>>> RocksDB store if we ever provide one) > > >>>>>>>>>>>>>>>>>>>>>> 2b) same as 2a but we throw an exception if the > > >>>>>> requested > > >>>>>>>>>>>>>>> store > > >>>>>>>>>>>>>>>>> type > > >>>>>>>>>>>>>>>>>>> does > > >>>>>>>>>>>>>>>>>>>>>> not support that (this is backwards incompatible, > > >>>>>> and since > > >>>>>>>>>>>>>>>>> ROCKS_DB > > >>>>>>>>>>>>>>>>>>> is the > > >>>>>>>>>>>>>>>>>>>>>> default we probably shouldn't do this) > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>> My proposal for now is 1) because as of KIP-825 > > >>>>>>>>>>>>>>>>>>>>>> EmitStrategy#ON_WINDOW_CLOSE is the preferred way of > > >>>>>>>>>>>>>>> suppressing > > >>>>>>>>>>>>>>>>> and > > >>>>>>>>>>>>>>>>>>> that > > >>>>>>>>>>>>>>>>>>>>>> is accounted for in this API already. > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> Last, I am not sure if the new parameter replacing > > >>>>>> the > > >>>>>>>>>>>>>>> existing > > >>>>>>>>>>>>>>>>> one > > >>>>>>>>>>>>>>>>>>> is > > >>>>>>>>>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>>>>> best way to go? > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>> I'm happy either way, just let me know which you > > >>>>>> prefer - > > >>>>>>>> the > > >>>>>>>>>>>>>>>>>>> discussion > > >>>>>>>>>>>>>>>>>>>>>> around CUSTOM is in the rejected alternatives but > > I'm > > >>>>>>>> happy to > > >>>>>>>>>>>>>>>>>>> differ to > > >>>>>>>>>>>>>>>>>>>>>> whatever the project conventions are :) > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> If it's matches existing `ROCKS_DB` or `IN_MEMORY` > > >>>>>> we just > > >>>>>>>>>>>>>>>> process > > >>>>>>>>>>>>>>>>>>> it as > > >>>>>>>>>>>>>>>>>>>>>> we > > >>>>>>>>>>>>>>>>>>>>>> do know, and if know we assume it's a fully > > >>>>>> qualified class > > >>>>>>>>>>>>>>> name > > >>>>>>>>>>>>>>>>> and > > >>>>>>>>>>>>>>>>>>> try to > > >>>>>>>>>>>>>>>>>>>>>> instantiate it? > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>> Note that there is no functionality for this kind of > > >>>>>> thing > > >>>>>>>> in > > >>>>>>>>>>>>>>>>>>>>>> AbstractConfig (it's either a String validated enum > > >>>>>> or a > > >>>>>>>>>>>>>>> class) > > >>>>>>>>>>>>>>>> so > > >>>>>>>>>>>>>>>>>>> this > > >>>>>>>>>>>>>>>>>>>>>> would be a departure from convention. Again, I'm > > >>>>>> happy to > > >>>>>>>>>>>>>>>> implement > > >>>>>>>>>>>>>>>>>>> that if > > >>>>>>>>>>>>>>>>>>>>>> it's preferred. > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> Also wondering how it would related to the existing > > >>>>>>>> `Stores` > > >>>>>>>>>>>>>>>>>>> factory? > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>> StoreTypeSpec will depend on Stores factory - > > >>>>>> they're one > > >>>>>>>>>>>>>>> layer > > >>>>>>>>>>>>>>>>>>> removed. > > >>>>>>>>>>>>>>>>>>>>>> You can imagine that StoreTypeSpec is just a > > >>>>>> grouping of > > >>>>>>>>>>>>>>> methods > > >>>>>>>>>>>>>>>>>>> from the > > >>>>>>>>>>>>>>>>>>>>>> Stores factory into a convenient package for default > > >>>>>>>>>>>>>>>> configuration > > >>>>>>>>>>>>>>>>>>>>>> purposes. > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>> Thanks again for all the detailed thoughts Matthias! > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>> On Fri, Jul 21, 2023 at 11:50 AM Matthias J. Sax < > > >>>>>>>>>>>>>>>> mj...@apache.org > > >>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> wrote: > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> Thanks for the KIP. Overall I like the idea to > > >>>>>> close this > > >>>>>>>>>>>>>>> gap. > > >>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> However, I am wondering if we should close others > > >>>>>> gaps > > >>>>>>>>>>>>>>> first? In > > >>>>>>>>>>>>>>>>>>>>>>> particular, IIRC, we have a few cases for which we > > >>>>>> only > > >>>>>>>> have > > >>>>>>>>>>>>>>> a > > >>>>>>>>>>>>>>>>>>> RocksDB > > >>>>>>>>>>>>>>>>>>>>>>> implementation for a store, and thus, adding an > > >>>>>> in-memory > > >>>>>>>>>>>>>>>> version > > >>>>>>>>>>>>>>>>>>> for > > >>>>>>>>>>>>>>>>>>>>>>> these stores first, to make the current `IN_MEMORY` > > >>>>>>>> parameter > > >>>>>>>>>>>>>>>>> work, > > >>>>>>>>>>>>>>>>>>>>>>> might be the first step? > > >>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> In particular, this holds for the new > > >>>>>> versioned-store > > >>>>>>>> (but I > > >>>>>>>>>>>>>>>>>>> actually > > >>>>>>>>>>>>>>>>>>>>>>> believe the is some other internal store with no > > >>>>>> in-memory > > >>>>>>>>>>>>>>>>>>>>>>> implementation). -- For `suppress()` it's actually > > >>>>>> other > > >>>>>>>> way > > >>>>>>>>>>>>>>>>> around > > >>>>>>>>>>>>>>>>>>> we > > >>>>>>>>>>>>>>>>>>>>>>> we only have an in-memory implementation. Do you > > >>>>>> aim to > > >>>>>>>> allow > > >>>>>>>>>>>>>>>>> custom > > >>>>>>>>>>>>>>>>>>>>>>> stores for `suppress()`, too? > > >>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> Btw: Should versioned stores also be covered by the > > >>>>>> KIP > > >>>>>>>> (ie, > > >>>>>>>>>>>>>>>>>>>>>>> `StoreTypeSpec`)? We did consider to add a new > > >>>>>> option > > >>>>>>>>>>>>>>>> `VERSIONED` > > >>>>>>>>>>>>>>>>>>> to the > > >>>>>>>>>>>>>>>>>>>>>>> existing `default.dsl.store` config, but opted out > > >>>>>> for > > >>>>>>>>>>>>>>> various > > >>>>>>>>>>>>>>>>>>> reasons. > > >>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> Last, I am not sure if the new parameter replacing > > >>>>>> the > > >>>>>>>>>>>>>>> existing > > >>>>>>>>>>>>>>>>> one > > >>>>>>>>>>>>>>>>>>> is > > >>>>>>>>>>>>>>>>>>>>>>> the best way to go? Did you put the idea to add > > >>>>>> `CUSTOM` > > >>>>>>>> to > > >>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>> existing > > >>>>>>>>>>>>>>>>>>>>>>> config into rejected alternative. Personally, I > > >>>>>> would > > >>>>>>>> prefer > > >>>>>>>>>>>>>>> to > > >>>>>>>>>>>>>>>>> add > > >>>>>>>>>>>>>>>>>>>>>>> `CUSTOM` as I would like to optimize to easy of use > > >>>>>> for > > >>>>>>>> the > > >>>>>>>>>>>>>>>>>>> majority of > > >>>>>>>>>>>>>>>>>>>>>>> users (which don't implement a custom store), but > > >>>>>> only > > >>>>>>>>>>>>>>> switch to > > >>>>>>>>>>>>>>>>>>>>>>> in-memory sometimes. -- As an alternative, you > > >>>>>> would also > > >>>>>>>>>>>>>>> just > > >>>>>>>>>>>>>>>>>>> extend > > >>>>>>>>>>>>>>>>>>>>>>> `dsl.default.store` (it's just a String) and allow > > >>>>>> to > > >>>>>>>> pass in > > >>>>>>>>>>>>>>>>>>> anything. > > >>>>>>>>>>>>>>>>>>>>>>> If it's matches existing `ROCKS_DB` or `IN_MEMORY` > > >>>>>> we just > > >>>>>>>>>>>>>>>> process > > >>>>>>>>>>>>>>>>>>> it as > > >>>>>>>>>>>>>>>>>>>>>>> we do know, and if know we assume it's a fully > > >>>>>> qualified > > >>>>>>>>>>>>>>> class > > >>>>>>>>>>>>>>>>> name > > >>>>>>>>>>>>>>>>>>> and > > >>>>>>>>>>>>>>>>>>>>>>> try to instantiate it? -- Given that we plan to > > >>>>>> keep the > > >>>>>>>>>>>>>>>>>>> store-enum, is > > >>>>>>>>>>>>>>>>>>>>>>> seems cleaner to keep the existing config and keep > > >>>>>> both > > >>>>>>>> the > > >>>>>>>>>>>>>>>> config > > >>>>>>>>>>>>>>>>>>> and > > >>>>>>>>>>>>>>>>>>>>>>> enum aligned to each other? > > >>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> It's just preliminary thought. I will need to go > > >>>>>> back an > > >>>>>>>>>>>>>>> take a > > >>>>>>>>>>>>>>>>> more > > >>>>>>>>>>>>>>>>>>>>>>> detailed look into the code to grok how the propose > > >>>>>>>>>>>>>>>>> `StoreTypeSpec` > > >>>>>>>>>>>>>>>>>>>>>>> falls into place. Also wondering how it would > > >>>>>> related to > > >>>>>>>> the > > >>>>>>>>>>>>>>>>>>> existing > > >>>>>>>>>>>>>>>>>>>>>>> `Stores` factory? > > >>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> -Matthias > > >>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> On 7/21/23 6:45 AM, Colt McNealy wrote: > > >>>>>>>>>>>>>>>>>>>>>>>> Sophie— > > >>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>> Thanks for chiming in here. +1 to the idea of > > >>>>>> specifying > > >>>>>>>> the > > >>>>>>>>>>>>>>>>>>> ordering > > >>>>>>>>>>>>>>>>>>>>>>>> guarantees that we make in the StorageTypeSpec > > >>>>>> javadocs. > > >>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>> Quick question then. Is the javadoc that says: > > >>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>>> Order is not guaranteed as bytes lexicographical > > >>>>>>>> ordering > > >>>>>>>>>>>>>>>> might > > >>>>>>>>>>>>>>>>>>> not > > >>>>>>>>>>>>>>>>>>>>>>>> represent key order. > > >>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>> no longer correct, and should say: > > >>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>>> Order guarantees depend on the underlying > > >>>>>>>> implementation of > > >>>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>>>>>>> ReadOnlyKeyValueStore. For more information, > > please > > >>>>>>>> consult > > >>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>>>>>>> [StorageTypeSpec javadocs](....) > > >>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>> Thanks, > > >>>>>>>>>>>>>>>>>>>>>>>> Colt McNealy > > >>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>> *Founder, LittleHorse.dev* > > >>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>> On Thu, Jul 20, 2023 at 9:28 PM Sophie > > >>>>>> Blee-Goldman < > > >>>>>>>>>>>>>>>>>>>>>>> ableegold...@gmail.com> > > >>>>>>>>>>>>>>>>>>>>>>>> wrote: > > >>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>>> Hey Almog, first off, thanks for the KIP! I (and > > >>>>>> others) > > >>>>>>>>>>>>>>>> raised > > >>>>>>>>>>>>>>>>>>>>>> concerns > > >>>>>>>>>>>>>>>>>>>>>>>>> over how restrictive the default.dsl.store config > > >>>>>> would > > >>>>>>>> be > > >>>>>>>>>>>>>>> if > > >>>>>>>>>>>>>>>>> not > > >>>>>>>>>>>>>>>>>>>>>>>>> extendable to custom store types, especially > > >>>>>> given that > > >>>>>>>>>>>>>>> this > > >>>>>>>>>>>>>>>>>>> seems to > > >>>>>>>>>>>>>>>>>>>>>> be > > >>>>>>>>>>>>>>>>>>>>>>>>> the primary userbase of such a feature. At the > > >>>>>> time we > > >>>>>>>>>>>>>>> didn't > > >>>>>>>>>>>>>>>>>>> really > > >>>>>>>>>>>>>>>>>>>>>>> have > > >>>>>>>>>>>>>>>>>>>>>>>>> any better ideas for a clean way to achieve that, > > >>>>>> but > > >>>>>>>> what > > >>>>>>>>>>>>>>> you > > >>>>>>>>>>>>>>>>>>>>>> proposed > > >>>>>>>>>>>>>>>>>>>>>>>>> makes a lot of sense to me. Happy to see a good > > >>>>>>>> solution to > > >>>>>>>>>>>>>>>>> this, > > >>>>>>>>>>>>>>>>>>> and > > >>>>>>>>>>>>>>>>>>>>>>>>> hopefully others will share my satisfaction :P > > >>>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>>> I did have one quick piece of feedback which > > >>>>>> arose from > > >>>>>>>> an > > >>>>>>>>>>>>>>>>>>> unrelated > > >>>>>>>>>>>>>>>>>>>>>>>>> question posed to the dev mailing list w/ subject > > >>>>>> line > > >>>>>>>>>>>>>>>>>>>>>>>>> "ReadOnlyKeyValueStore#range() > > >>>>>>>>>>>>>>>>>>>>>>>>> Semantics" > > >>>>>>>>>>>>>>>>>>>>>>>>> < > > >>>>>>>>>>>>>>>>> > > >>>>>>>> https://lists.apache.org/thread/jbckmth8d3mcgg0rd670cpvsgwzqlwrm > > >. > > >>>>>>>>>>>>>>>>>>> I > > >>>>>>>>>>>>>>>>>>>>>>>>> recommend checking out the full thread for > > >>>>>> context, but > > >>>>>>>> it > > >>>>>>>>>>>>>>>> made > > >>>>>>>>>>>>>>>>> me > > >>>>>>>>>>>>>>>>>>>>>> think > > >>>>>>>>>>>>>>>>>>>>>>>>> about how we can leverage the new StoreTypeSpec > > >>>>>> concept > > >>>>>>>> as > > >>>>>>>>>>>>>>> an > > >>>>>>>>>>>>>>>>>>> answer > > >>>>>>>>>>>>>>>>>>>>>> to > > >>>>>>>>>>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>>>>>>>> long-standing question in Streams: where can we > > >>>>>> put > > >>>>>>>>>>>>>>> guarantees > > >>>>>>>>>>>>>>>>> of > > >>>>>>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>>>>>>>> public contract for RocksDB (or other store > > >>>>>>>>>>>>>>> implementations) > > >>>>>>>>>>>>>>>>> when > > >>>>>>>>>>>>>>>>>>> all > > >>>>>>>>>>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>>>>>>>> RocksDB stuff is technically internal. > > >>>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>>> Basically, I'm suggesting two things: first, call > > >>>>>> out in > > >>>>>>>>>>>>>>> some > > >>>>>>>>>>>>>>>>> way > > >>>>>>>>>>>>>>>>>>>>>>> (perhaps > > >>>>>>>>>>>>>>>>>>>>>>>>> the StoreTypeSpec javadocs) that each > > >>>>>> StoreTypeSpec is > > >>>>>>>>>>>>>>>>> considered > > >>>>>>>>>>>>>>>>>>> a > > >>>>>>>>>>>>>>>>>>>>>>> public > > >>>>>>>>>>>>>>>>>>>>>>>>> contract in itself and should outline any > > semantic > > >>>>>>>>>>>>>>> guarantees > > >>>>>>>>>>>>>>>> it > > >>>>>>>>>>>>>>>>>>> does, > > >>>>>>>>>>>>>>>>>>>>>>> or > > >>>>>>>>>>>>>>>>>>>>>>>>> does not, make. Second, we should add a note on > > >>>>>> ordering > > >>>>>>>>>>>>>>>>>>> guarantees in > > >>>>>>>>>>>>>>>>>>>>>>> the > > >>>>>>>>>>>>>>>>>>>>>>>>> two OOTB specs: for RocksDB we assert that range > > >>>>>> queries > > >>>>>>>>>>>>>>> will > > >>>>>>>>>>>>>>>>>>> honor > > >>>>>>>>>>>>>>>>>>>>>>>>> serialized byte ordering, whereas the InMemory > > >>>>>> flavor > > >>>>>>>>>>>>>>> gives no > > >>>>>>>>>>>>>>>>>>>>>> ordering > > >>>>>>>>>>>>>>>>>>>>>>>>> guarantee whatsoever at this time. > > >>>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>>> Thoughts? > > >>>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>>> -Sophie > > >>>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>>> On Thu, Jul 20, 2023 at 4:28 PM Almog Gavra < > > >>>>>>>>>>>>>>>>>>> almog.ga...@gmail.com> > > >>>>>>>>>>>>>>>>>>>>>>> wrote: > > >>>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>>>> Hi All, > > >>>>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>>>> I would like to propose a KIP to expand support > > >>>>>> for > > >>>>>>>>>>>>>>> default > > >>>>>>>>>>>>>>>>> store > > >>>>>>>>>>>>>>>>>>>>>> types > > >>>>>>>>>>>>>>>>>>>>>>>>>> (KIP-591) to encompass custom store > > >>>>>> implementations: > > >>>>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>> > > >>>>>>>>>>>> > > >>>>>>>>>>> > > >>>>>>>> > > >>>>>> > > >> > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-954%3A+expand+default+DSL+store+configuration+to+custom+types > > >>>>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>>>> Looking forward to your feedback! > > >>>>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>>>> Cheers, > > >>>>>>>>>>>>>>>>>>>>>>>>>> Almog > > >>>>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>>> > > >>>>>>>>>>>>>>> > > >>>>>>>>>>>>>> > > >>>>>>>>>>>>> > > >>>>>>>>>>>> > > >>>>>>>>>>> > > >>>>>>>>>> > > >>>>>>>> > > >>>>>> > > >>>>> > > >>> > > >> > > > > >
