Hi Ryan, You are right: I can't access the document either. AFAIR, Jack did the doc, he will fix that soon I'm sure.
Regards JB On Wed, Jun 19, 2024 at 1:17 AM Ryan Blue <b...@tabular.io> wrote: > It looks like the design doc from the original email is no longer > available. Could someone fix the permissions? > > On Mon, May 20, 2024 at 8:10 AM Jack Ye <yezhao...@gmail.com> wrote: > >> We merged the spec change for content file in >> https://github.com/apache/iceberg/pull/9717, the next step is to merge >> the PlanTable and PreplanTable API spec change in >> https://github.com/apache/iceberg/pull/9695. I guess people were a bit >> busy in the past few weeks due to the Iceberg summit, you should see more >> progress pretty soon! >> >> Best, >> Jack Ye >> >> On Sat, May 18, 2024 at 4:05 PM Pucheng Yang <py...@pinterest.com.invalid> >> wrote: >> >>> Hi all, I wonder if we have a ETA for this change? thanks >>> >>> On Wed, Jan 31, 2024 at 10:30 AM Chertara, Rahil >>> <rcher...@amazon.com.invalid> wrote: >>> >>>> Sure, I can look into adding this to the spec. >>>> Thanks to everyone for sharing their thoughts, appreciate it! >>>> >>>> >>>> >>>> *From: *Ryan Blue <b...@tabular.io> >>>> *Reply-To: *"dev@iceberg.apache.org" <dev@iceberg.apache.org> >>>> *Date: *Wednesday, January 31, 2024 at 10:22 AM >>>> *To: *"dev@iceberg.apache.org" <dev@iceberg.apache.org> >>>> *Subject: *RE: [EXTERNAL] Proposal for REST APIs for Iceberg table >>>> scans >>>> >>>> >>>> >>>> *CAUTION*: This email originated from outside of the organization. Do >>>> not click links or open attachments unless you can confirm the sender and >>>> know the content is safe. >>>> >>>> >>>> >>>> Looks good to me! Should we get a PR up to add it to the OpenAPI spec? >>>> >>>> >>>> >>>> On Wed, Jan 31, 2024 at 10:16 AM Jack Ye <yezhao...@gmail.com> wrote: >>>> >>>> Sounds good. I don't really have any strong opinions here. So looks >>>> like we are landing on this? >>>> >>>> >>>> >>>> >>>> *PreplanTable: POST /v1/namespaces/ns/tables/t/preplan *{ "filter": { >>>> "type": "in", "term": "x", "values": [1, 2, 3] }, "select": ["x", "a.b"] } >>>> >>>> { "plan-tasks": [ { ... }, { ... } ] } // opaque object >>>> >>>> >>>> *PlanTable w/o a plan task: POST /v1/namespaces/ns/tables/t/plan *{ >>>> "filter": {"type": "in", "term": "x", "values": [1, 2, 3] }, "select": >>>> ["x", "a.b"] } >>>> >>>> >>>> { "file-scan-tasks": [ { ... }, { ... } ] } // FileScanTask OpenAPI >>>> model >>>> >>>> >>>> >>>> *PlanTable w/ a plan task: POST /v1/namespaces/ns/tables/t/plan *{ >>>> "filter": {"type": "in", "term": "x", "values": [1, 2, 3] }, "select": >>>> ["x", "a.b"], "plan-task": { ... } } >>>> >>>> { "file-scan-tasks": [ { ... }, { ... } ] } >>>> >>>> >>>> >>>> -Jack >>>> >>>> >>>> >>>> On Wed, Jan 31, 2024 at 10:08 AM Ryan Blue <b...@tabular.io> wrote: >>>> >>>> I agree with Dan. I'd rather have two endpoints instead of needing an >>>> option that changes the behavior entirely in the same route. I don't think >>>> that a `preplan` route would be too bad. >>>> >>>> >>>> >>>> On Wed, Jan 31, 2024 at 9:51 AM Daniel Weeks <dwe...@apache.org> wrote: >>>> >>>> I agree with the opaque tokens. >>>> >>>> >>>> >>>> However, I'm concerned we're overloading the endpoint two perform two >>>> distinctly different operations: distribute a plan and scan a plan. >>>> >>>> >>>> >>>> Changing the task-type then changes the behavior and the result. I >>>> feel it would be more straightforward to separate the distribute and scan >>>> endpoints. Then clients can call the scan directly if they do not know how >>>> to distribute and the behavior is clear from the REST Specification. >>>> >>>> >>>> >>>> -Dan >>>> >>>> >>>> >>>> On Tue, Jan 30, 2024 at 9:09 PM Jack Ye <yezhao...@gmail.com> wrote: >>>> >>>> +1 for having the opaque plan tasks, that's probably the most flexible >>>> way forward. And let's call them *plan tasks* going forward to >>>> standardize the terminology. >>>> >>>> >>>> >>>> I think the name of the APIs can be determined based on the actual API >>>> shape. For example, if we centralize these 2 plan and pre-plan actions to a >>>> single API endpoint but just requesting different task types: >>>> >>>> >>>> >>>> >>>> *pre-plan: POST /v1/namespaces/ns/tables/t/plan *{ "filter": { "type": >>>> "in", "term": "x", "values": [1, 2, 3] }, "select": ["x", "a.b"], >>>> "task-type": "plan-task" } >>>> >>>> { "plan-tasks": [ { ... }, { ... } ] } >>>> >>>> >>>> *plan without a plan-task: POST /v1/namespaces/ns/tables/t/plan *{ >>>> "filter": {"type": "in", "term": "x", "values": [1, 2, 3] }, "select": >>>> ["x", "a.b"], "task-type": "file-scan-task" } // file-scan-task should be >>>> the default type >>>> >>>> >>>> { "file-scan-tasks": [ { ... }, { ... } ] } >>>> >>>> >>>> >>>> *plan with a plan-task: POST /v1/namespaces/ns/tables/t/plan *{ >>>> "filter": {"type": "in", "term": "x", "values": [1, 2, 3] }, "select": >>>> ["x", "a.b"], "task-type": "file-scan-task", "plan-task": { ... } } >>>> >>>> { "file-scan-tasks": [...] } >>>> >>>> >>>> >>>> In this model, we just have a single API, and we can call it something >>>> like PlanTable or PlanTableScan. >>>> >>>> >>>> >>>> What do you think? >>>> >>>> >>>> >>>> -Jack >>>> >>>> >>>> >>>> >>>> >>>> On Mon, Jan 29, 2024 at 6:17 PM Renjie Liu <liurenjie2...@gmail.com> >>>> wrote: >>>> >>>> But to move forward, I think we should go with the option that >>>> preserves flexibility. I think the spec should state that plan tasks (if we >>>> call them that) are a JSON object that should be sent as-is back to the >>>> REST service to be used. >>>> >>>> >>>> >>>> +1 for this. >>>> >>>> >>>> >>>> > One more thing that I would also change is that I don't think the >>>> "plan" and "scan" endpoints make much sense. We refer to the "scan" portion >>>> of this as "planFiles" in the reference implementation, and "scan" is used >>>> for actually reading data. To be less confusing, I think that file scan >>>> tasks should be returned by a "plan" endpoint and the manifest plan tasks >>>> (or shards) should be returned by a "pre-plan" endpoint. Does anyone else >>>> like the names "pre-plan" and "plan" better? >>>> >>>> >>>> >>>> I agree that "scan" may be quite confusing since it's actually planning >>>> file scan. Another options I can provide is: "plan" -> "plan-table-scan", >>>> "scan" -> "plan-file-scan" >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> On Tue, Jan 30, 2024 at 9:03 AM Ryan Blue <b...@tabular.io> wrote: >>>> >>>> As you noted the main point we still need to decide on is whether to >>>> have a standard "shard" definition (e.g. manifest plan task) or to allow it >>>> to be opaque and specific to catalogs implementing the protocol. I've not >>>> replied because I keep coming back to this decision and I'm not sure >>>> whether the advantage is being clear about how it works (being explicit) or >>>> allowing implementations to differ (opaque). I'm skeptical that there will >>>> be other strategies. >>>> >>>> >>>> >>>> But to move forward, I think we should go with the option that >>>> preserves flexibility. I think the spec should state that plan tasks (if we >>>> call them that) are a JSON object that should be sent as-is back to the >>>> REST service to be used. >>>> >>>> >>>> >>>> One more thing that I would also change is that I don't think the >>>> "plan" and "scan" endpoints make much sense. We refer to the "scan" portion >>>> of this as "planFiles" in the reference implementation, and "scan" is used >>>> for actually reading data. To be less confusing, I think that file scan >>>> tasks should be returned by a "plan" endpoint and the manifest plan tasks >>>> (or shards) should be returned by a "pre-plan" endpoint. Does anyone else >>>> like the names "pre-plan" and "plan" better? >>>> >>>> >>>> >>>> Ryan >>>> >>>> >>>> >>>> On Mon, Jan 29, 2024 at 12:02 PM Chertara, Rahil >>>> <rcher...@amazon.com.invalid> wrote: >>>> >>>> Hi All hope everyone is doing well, >>>> >>>> >>>> Wanted to revive the discussion around the Rest Table Scan API work. >>>> For a refresher here is the original proposal: >>>> https://docs.google.com/document/d/1FdjCnFZM1fNtgyb9-v9fU4FwOX4An-pqEwSaJe8RgUg/edit#heading=h.cftjlkb2wh4h >>>> as well as the PR: https://github.com/apache/iceberg/pull/9252 >>>> >>>> >>>> From the last messages on the thread, I believe Ryan and Jack were in >>>> favor of having two distinct api endpoints /plan and /scan, as well as a >>>> stricter json definition for the "shard”, here is an example below from >>>> what was discussed. >>>> >>>> >>>> *POST /v1/namespaces/ns/tables/t/plan *{ "filter": { "type": "in", >>>> "term": "x", "values": [1, 2, 3] }, "select": ["x", "a.b"]} >>>> >>>> { "manifest-plan-tasks": [ >>>> { "start": 0, "length": 1000, "manifest": { "path": >>>> "s3://some/manifest.avro", ...}, "delete-manifests": [...] }, >>>> { ... } >>>> ]} >>>> >>>> >>>> *POST /v1/namespaces/ns/tables/t/scan *{ "filter": {"type": "in", >>>> "term": "x", "values": [1, 2, 3] }, >>>> >>>> "select": ["x", "a.b"], >>>> "manifest-plan-task": { "start": 0, "length": 1000, "manifest": { >>>> "path": "s3://some/manifest.avro", ...}, "delete-manifests": [...] } } >>>> >>>> { "file-scan-tasks": [...] } >>>> >>>> >>>> *POST /v1/namespaces/ns/tables/t/scan *{ "filter": {"type": "in", >>>> "term": "x", "values": [1, 2, 3] }, "select": ["x", "a.b"]} >>>> >>>> >>>> { "file-scan-tasks": [...] } >>>> >>>> >>>> >>>> However IIRC Micah and Renjie had some concerns around this stricter >>>> structure as this can make it harder to evolve in the future, as well as >>>> some potential scalability challenges for larger tables that have many >>>> manifest files. (Feel free to expand further on the concerns if my >>>> understanding is incorrect). >>>> >>>> >>>> >>>> Would appreciate if the community can leave any more thoughts/feedback >>>> on this thread, as well as on the google doc, and the PR. >>>> >>>> >>>> >>>> Regards, >>>> Rahil Chertara >>>> >>>> >>>> >>>> *From: *Renjie Liu <liurenjie2...@gmail.com> >>>> *Reply-To: *"dev@iceberg.apache.org" <dev@iceberg.apache.org> >>>> *Date: *Thursday, December 21, 2023 at 10:35 PM >>>> *To: *"dev@iceberg.apache.org" <dev@iceberg.apache.org> >>>> *Subject: *RE: [EXTERNAL] Proposal for REST APIs for Iceberg table >>>> scans >>>> >>>> >>>> >>>> *CAUTION*: This email originated from outside of the organization. Do >>>> not click links or open attachments unless you can confirm the sender and >>>> know the content is safe. >>>> >>>> >>>> >>>> I share the same concern with Micah. The shard detail should be >>>> implementation details of the server, rather than exposing directly to the >>>> client. If the goal is to make things stateless, we just need to attach a >>>> snapshot id + shard id, then a determined algorithm is supposed to give the >>>> same result. Also another concern is for huge analytics tables, we may have >>>> a lot of manifest files, which may lead to large traffic from the rest >>>> server. >>>> >>>> >>>> >>>> On Thu, Dec 21, 2023 at 7:41 AM Micah Kornfield <emkornfi...@gmail.com> >>>> wrote: >>>> >>>> Also +1 for having a more strict definition of the shard. Having >>>> arbitrary JSON was basically what we experimented with a string shard ID, >>>> and we ended up with something very similar to the manifest plan task you >>>> describe in the serialized ID string. >>>> >>>> >>>> >>>> IIUC the proposal correctly, I'd actually be -0.0 on the stricter >>>> structure. I think forcing a contract where it isn't strictly necessary >>>> makes it harder to evolve the system in the future. For example it makes >>>> it harder to address potential scalability problems in a transparent way >>>> (e.g. extreme edge cases in cardinality between manifest files and delete >>>> files). >>>> >>>> >>>> >>>> It also seems like it might overly constrain implementations (it is not >>>> clear we should need to compute the mapping between delete file manifests >>>> to data file manifests up front to start planning). >>>> >>>> >>>> >>>> On Tue, Dec 19, 2023 at 2:10 PM Jack Ye <yezhao...@gmail.com> wrote: >>>> >>>> +1 for having /plan and /scan, sounds like a good idea to separate >>>> those 2 distinct actions. >>>> >>>> >>>> >>>> Also +1 for having a more strict definition of the shard. Having >>>> arbitrary JSON was basically what we experimented with a string shard ID, >>>> and we ended up with something very similar to the manifest plan task you >>>> describe in the serialized ID string. >>>> >>>> >>>> >>>> So sounds like we are converging to the following APIs: >>>> >>>> >>>> >>>> >>>> *POST /v1/namespaces/ns/tables/t/plan *{ "filter": { "type": "in", >>>> "term": "x", "values": [1, 2, 3] }, "select": ["x", "a.b"]} >>>> >>>> { "manifest-plan-tasks": [ >>>> { "start": 0, "length": 1000, "manifest": { "path": >>>> "s3://some/manifest.avro", ...}, "delete-manifests": [...] }, >>>> { ... } >>>> ]} >>>> >>>> >>>> *POST /v1/namespaces/ns/tables/t/scan *{ "filter": {"type": "in", >>>> "term": "x", "values": [1, 2, 3] }, >>>> >>>> "select": ["x", "a.b"], >>>> "manifest-plan-task": { "start": 0, "length": 1000, "manifest": { >>>> "path": "s3://some/manifest.avro", ...}, "delete-manifests": [...] } } >>>> >>>> { "file-scan-tasks": [...] } >>>> >>>> >>>> *POST /v1/namespaces/ns/tables/t/scan *{ "filter": {"type": "in", >>>> "term": "x", "values": [1, 2, 3] }, "select": ["x", "a.b"]} >>>> >>>> >>>> { "file-scan-tasks": [...] } >>>> >>>> >>>> >>>> If this sounds good overall, we can update the prototype to have more >>>> detailed discussions in code. >>>> >>>> >>>> >>>> -Jack >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> On Thu, Dec 14, 2023 at 6:10 PM Ryan Blue <b...@tabular.io> wrote: >>>> >>>> The tasks might look something like this: >>>> >>>> >>>> >>>> CombinedPlanTask >>>> >>>> - List<ManifestPlanTask> >>>> >>>> >>>> >>>> ManifestPlanTask >>>> >>>> - int start >>>> >>>> - int length >>>> >>>> - ManifestFile dataManifest >>>> >>>> - List<ManifestFile> deleteManifests >>>> >>>> >>>> >>>> On Thu, Dec 14, 2023 at 4:07 PM Ryan Blue <b...@tabular.io> wrote: >>>> >>>> Seems like that track has expired (This Internet-Draft will expire on >>>> 13 May 2022) >>>> >>>> Yeah, looks like we should just use POST. That’s too bad. QUERY seems >>>> like a good idea to me. >>>> >>>> Distinguish planning using shard or not >>>> >>>> I think this was a mistake on my part. I was still thinking that we >>>> would have a different endpoint for first-level planning to produce shards >>>> and the route to actually get files. Since both are POST requests with the >>>> same path (/v1/namespaces/ns/tables/t/scans) that no longer works. >>>> What about /v1/namespaces/ns/tables/t/scan and >>>> /v1/namespaces/ns/tables/t/plan? The latter could use some variant of >>>> planFiles since that’s what we are wrapping in the Java API. >>>> >>>> Necessity of scan ID >>>> >>>> Yes, I agree. If you have shard IDs then you don’t really need a scan >>>> ID. You could always have one internally but send it as part of the shard >>>> ID. >>>> >>>> Shape of shard payload >>>> >>>> I think we have 2 general options depending on how strict we want to be. >>>> >>>> 1. Require a standard shard definition >>>> 2. Allow arbitrary JSON and leave it to the service >>>> >>>> I lean toward the first option, which would be a data manifest and the >>>> associated delete manifests for the partition. We could also extend that to >>>> a group of manifests, each with a list of delete manifests. And we could >>>> also allow splitting to ensure tasks don’t get too large with big files. >>>> This all looks basically like FileScanTask, but with manifests and delete >>>> manifests. >>>> >>>> >>>> >>>> On Wed, Dec 13, 2023 at 4:39 PM Jack Ye <yezhao...@gmail.com> wrote: >>>> >>>> Seems like that track has expired (This Internet-Draft will expire on >>>> 13 May 2022), not sure how these RFCs are managed, but it does not seem >>>> hopeful to have this verb in. I think people are mostly using POST for this >>>> use case already. >>>> >>>> >>>> >>>> But overall I think we are in agreement with the general direction. A >>>> few detail discussions: >>>> >>>> >>>> >>>> *Distinguish planning using shard or not* >>>> >>>> Maybe we should add a query parameter like *distributed=true* to >>>> distinguish your first and third case, since they are now sharing the same >>>> signature. If the requester wants to use distributed planning, then some >>>> sharding strategy is provided as a response for the requester to send more >>>> detailed requests. >>>> >>>> *Necessity of scan ID* >>>> In this approach, is scan ID still required? Because the shard payload >>>> already fully describes the information to retrieve, it seems like we can >>>> just drop the *scan-id* query parameter in the second case. Seems like >>>> it's kept for the case if we still want to persist some state, but it seems >>>> like we can make a stateless style fully working. >>>> >>>> *Shape of shard payload* >>>> What do you think is necessary information of the shard payload? It >>>> seems like we need at least the location of the manifests, plus the delete >>>> manifests or delete files associated with the manifests. I like the idea of >>>> making it a "shard task" that is similar to a file scan task, and it might >>>> allow us to return a mixture of both types of tasks, so we can have better >>>> control of the response size. >>>> >>>> -Jack >>>> >>>> >>>> >>>> On Wed, Dec 13, 2023 at 3:50 PM Ryan Blue <b...@tabular.io> wrote: >>>> >>>> I just changed it to POST after looking into support for the QUERY >>>> method. It's a new HTTP method for cases like this where you don't want to >>>> pass everything through query params. Here's the QUERY method RFC >>>> <https://www.ietf.org/archive/id/draft-ietf-httpbis-safe-method-w-body-02.html>, >>>> but I guess it isn't finalized yet? >>>> >>>> >>>> >>>> Just read them like you would a POST request that doesn't actually >>>> create anything. >>>> >>>> >>>> >>>> On Wed, Dec 13, 2023 at 3:45 PM Jack Ye <yezhao...@gmail.com> wrote: >>>> >>>> Thanks, the Gist explains a lot of things. This is actually very close >>>> to our way of implementing the shard ID, we were defining the shard ID as a >>>> string, and the string content is actually something similar to the >>>> information of the JSON payload you showed, so we can persist minimum >>>> information in storage. >>>> >>>> >>>> >>>> Just one clarification needed for your Gist: >>>> >>>> >>>> >>>> > QUERY /v1/namespaces/ns/tables/t/scans?scan-id=1 >>>> >>>> >>>> >>>> > { "shard": { "id": 1, "manifests": ["C"] }, "filter": {"type": "in", >>>> "term": "x", "values": [1, 2, 3] } } >>>> >>>> >>>> >>>> > >>>> >>>> > { "file-scan-tasks": [...] } >>>> >>>> >>>> >>>> Here, what does this QUERY verb mean? Is that a GET? If it's GET, we >>>> cannot have a request body. That's actually why we expressed that as an ID >>>> string, since we can put it as a query parameter. >>>> >>>> >>>> >>>> -Jack >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> On Wed, Dec 13, 2023 at 3:25 PM Ryan Blue <b...@tabular.io> wrote: >>>> >>>> Jack, >>>> >>>> It sounds like what I’m proposing isn’t quite clear because your >>>> initial response was arguing for a sharding capability. I agree that >>>> sharding is a good idea. I’m less confident about two points: >>>> >>>> 1. Requiring that the service is stateful. As Renjie pointed out, >>>> that makes it harder to scale the service. >>>> 2. The need for both pagination *and* sharding as separate things >>>> >>>> And I also think that Fokko has a good point about trying to keep >>>> things simple and not requiring the CreateScan endpoint. >>>> >>>> For the first point, I’m proposing that we still have a CreateScan >>>> endpoint, but instead of sending only a list of shard IDs it can also send >>>> either a standard shard “task” or an optional JSON definition. Let’s assume >>>> we can send arbitrary JSON for an example. Say I have a table with 4 >>>> manifests, A through D and that C and D match some query filter. When >>>> I call the CreateScan endpoint, the service would send back tasks with >>>> that information: {"id": 1, "manifests": ["C"]}, {"id": 2, >>>> "manifests": ["D"]}. By sending what the shards mean (the manifests to >>>> read), my service can be stateless: any node can get a request for shard 1, >>>> read manifest C, and send back the resulting data files. >>>> >>>> I don’t see much of an argument against doing this *in principle*. It >>>> gives you the flexibility to store state if you choose or to send state to >>>> the client for it to pass back when calling the GetTasks endpoint. >>>> There is a practical problem, which is that it’s annoying to send a GET >>>> request with a JSON payload because you can’t send a request body. It’s >>>> probably obvious, but I’m also not a REST purist so I’d be fine using POST >>>> or QUERY for this. It would look something like this Gist >>>> <https://gist.github.com/rdblue/d2b65bd2ad20f85ee9d04ccf19ac8aba>. >>>> >>>> In your last reply, you also asked whether a stateless service is a >>>> goal. I don’t think that it is, but if we can make simple changes to the >>>> spec to allow more flexibility on the server side, I think that’s a good >>>> direction. You also asked about a reference implementation and I consider >>>> CatalogHandlers >>>> <https://github.com/apache/iceberg/blob/main/core/src/main/java/org/apache/iceberg/rest/CatalogHandlers.java> >>>> to be that reference. It does everything except for the work done by your >>>> choice of web application framework. It isn’t stateless, but it only relies >>>> on a Catalog implementation for persistence. >>>> >>>> For the second point, I don’t understand why we need both sharding and >>>> pagination. That is, if we have a protocol that allows sharding, why is >>>> pagination also needed? From my naive perspective on how sharding would >>>> work, we should be able to use metadata from the manifest list to limit the >>>> potential number of data files in a given shard. As long as we can limit >>>> the size of a shard to produce more, pagination seems like unnecessary >>>> complication. >>>> >>>> Lastly, for Fokko’s point, I think another easy extension to the >>>> proposal is to support a direct call to GetTasks. There’s a trade-off >>>> here, but if you’re already sending the original filter along with the >>>> request (in order to filter records from manifest C for instance) then >>>> the request is already something the protocol can express. There’s an >>>> objection concerning resource consumption on the service and creating >>>> responses that are too large or take too long, but we can get around that >>>> by responding with a code that instructs the client to use the >>>> CreateScan API like 413 (Payload too large). I think that would allow >>>> simple clients to function for all but really large tables. The gist above >>>> also shows what this might look like. >>>> >>>> Ryan >>>> >>>> >>>> >>>> On Wed, Dec 13, 2023 at 11:53 AM Jack Ye <yezhao...@gmail.com> wrote: >>>> >>>> The current proposal definitely makes the server stateful. In our >>>> prototype we used other components like DynamoDB to keep track of states. >>>> If keeping it stateless is a tenant we can definitely make the proposal >>>> closer to that direction. Maybe one thing to make sure is, is this a core >>>> tenant of the REST spec? Today we do not even have an official reference >>>> implementation of the REST server, I feel it is hard to say what are the >>>> core tenants. Maybe we should create one? >>>> >>>> >>>> >>>> Pagination is a common issue in the REST spec. We also see similar >>>> limitations with other APIs like GetTables, GetNamespaces. When a catalog >>>> has many namespaces and tables it suffers from the same issue. It is also >>>> not ideal for use cases like web browsers, since typically you display a >>>> small page of results and do not need the full list immediately. So I feel >>>> we cannot really avoid some state to be kept for those use cases. >>>> >>>> >>>> >>>> Chunked response might be a good way to work around it. We also thought >>>> about using HTTP2. However, these options seem to be not very compatible >>>> with OpenAPI. We can do some further research in this domain, would really >>>> appreciate it if anyone has more insights and experience with OpenAPI that >>>> can provide some suggestions. >>>> >>>> >>>> >>>> -Jack >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> On Tue, Dec 12, 2023 at 6:21 PM Renjie Liu <liurenjie2...@gmail.com> >>>> wrote: >>>> >>>> Hi, Rahi and Jack: >>>> >>>> Thanks for raising this. >>>> >>>> >>>> >>>> My question is that the pagination and sharding will make the rest >>>> server stateful, e.g. a sequence of calls is required to go to the same >>>> server. In this case, how do we ensure the scalability of the rest server? >>>> >>>> >>>> >>>> >>>> >>>> On Wed, Dec 13, 2023 at 4:09 AM Fokko Driesprong <fo...@apache.org> >>>> wrote: >>>> >>>> Hey Rahil and Jack, >>>> >>>> >>>> >>>> Thanks for bringing this up. Ryan and I also discussed this briefly in >>>> the early days of PyIceberg and it would have helped a lot in the speed of >>>> development. We went for the traditional approach because that would also >>>> support all the other catalogs, but now that the REST catalog is taking >>>> off, I think it still makes a lot of sense to get it in. >>>> >>>> >>>> >>>> I do share the concern raised Ryan around the concepts of shards and >>>> pagination. For PyIceberg (but also for Go, Rust, and DuckDB) that are >>>> living in a single process today the concept of shards doesn't add value. I >>>> see your concern with long-running jobs, but for the non-distributed cases, >>>> it will add additional complexity. >>>> >>>> >>>> >>>> Some suggestions that come to mind: >>>> >>>> - Stream the tasks directly back using a chunked response, reducing >>>> the latency to the first task. This would also solve things with the >>>> pagination. The only downside I can think of is having delete files >>>> where >>>> you first need to make sure there are deletes relevant to the task, this >>>> might increase latency to the first task. >>>> - Making the sharding optional. If you want to shard you call the >>>> CreateScan first and then call the GetScanTask with the IDs. If you >>>> don't >>>> want to shard, you omit the shard parameter and fetch the tasks directly >>>> (here we need also replace the scan string with the full >>>> column/expression/snapshot-id etc). >>>> >>>> Looking forward to discussing this tomorrow in the community sync >>>> <https://iceberg.apache.org/community/#iceberg-community-events>! >>>> >>>> >>>> >>>> Kind regards, >>>> >>>> Fokko >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> Op ma 11 dec 2023 om 19:05 schreef Jack Ye <yezhao...@gmail.com>: >>>> >>>> Hi Ryan, thanks for the feedback! >>>> >>>> >>>> >>>> I was a part of this design discussion internally and can provide more >>>> details. One reason for separating the CreateScan operation was to make the >>>> API asynchronous and thus keep HTTP communications short. Consider the case >>>> where we only have GetScanTasks API, and there is no shard specified. It >>>> might take tens of seconds, or even minutes to read through all the >>>> manifest list and manifests before being able to return anything. This >>>> means the HTTP connection has to remain open during that period, which is >>>> not really a good practice in general (consider connection failure, load >>>> balancer and proxy load, etc.). And when we shift the API to asynchronous, >>>> it basically becomes something like the proposal, where a stateful ID is >>>> generated to be able to immediately return back to the client, and the >>>> client get results by referencing the ID. So in our current prototype >>>> implementation we are actually keeping this ID and the whole REST service >>>> is stateful. >>>> >>>> >>>> >>>> There were some thoughts we had about the possibility to define a >>>> "shard ID generator" protocol: basically the client agrees with the service >>>> a way to deterministically generate shard IDs, and service uses it to >>>> create shards. That sounds like what you are suggesting here, and it pushes >>>> the responsibility to the client side to determine the parallelism. But in >>>> some bad cases (e.g. there are many delete files and we need to read all >>>> those in each shard to apply filters), it seems like there might still be >>>> the long open connection issue above. What is your thought on that? >>>> >>>> >>>> >>>> -Jack >>>> >>>> >>>> >>>> On Sun, Dec 10, 2023 at 10:27 AM Ryan Blue <b...@tabular.io> wrote: >>>> >>>> Rahil, thanks for working on this. It has some really good ideas that >>>> we hadn't considered before like a way for the service to plan how to break >>>> up the work of scan planning. I really like that idea because it makes it >>>> much easier for the service to keep memory consumption low across requests. >>>> >>>> >>>> >>>> My primary feedback is that I think it's a little too complicated (with >>>> both sharding and pagination) and could be modified slightly so that the >>>> service doesn't need to be stateful. If the service isn't necessarily >>>> stateful then it should be easier to build implementations. >>>> >>>> >>>> >>>> To make it possible for the service to be stateless, I'm proposing that >>>> rather than creating shard IDs that are tracked by the service, the >>>> information for a shard can be sent to the client. My assumption here is >>>> that most implementations would create shards by reading the manifest list, >>>> filtering on partition ranges, and creating a shard for some reasonable >>>> size of manifest content. For example, if a table has 100MB of metadata in >>>> 25 manifests that are about 4 MB each, then it might create 9 shards with >>>> 1-4 manifests each. The service could send those shards to the client as a >>>> list of manifests to read and the client could send the shard information >>>> back to the service to get the data files in each shard (along with the >>>> original filter). >>>> >>>> >>>> >>>> There's a slight trade-off that the protocol needs to define how to >>>> break the work into shards. I'm interested in hearing if that would work >>>> with how you were planning on building the service on your end. Another >>>> option is to let the service send back arbitrary JSON that would get >>>> returned for each shard. Either way, I like that this would make it so the >>>> service doesn't need to persist anything. We could also make it so that >>>> small tables don't require multiple requests. For example, a client could >>>> call the route to get file tasks with just a filter. >>>> >>>> >>>> >>>> What do you think? >>>> >>>> >>>> >>>> Ryan >>>> >>>> >>>> >>>> On Fri, Dec 8, 2023 at 10:41 AM Chertara, Rahil >>>> <rcher...@amazon.com.invalid> wrote: >>>> >>>> Hi all, >>>> >>>> My name is Rahil Chertara, and I’m a part of the Iceberg team at Amazon >>>> EMR and Athena. I’m reaching out to share a proposal for a new Scan API >>>> that will be utilized by the RESTCatalog. The process for table scan >>>> planning is currently done within client engines such as Apache Spark. By >>>> moving scan functionality to the RESTCatalog, we can integrate Iceberg >>>> table scans with external services, which can lead to several benefits. >>>> >>>> For example, we can leverage caching and indexes on the server side to >>>> improve planning performance. Furthermore, by moving this scan logic to the >>>> RESTCatalog, non-JVM engines can integrate more easily. This all can be >>>> found in the detailed proposal below. Feel free to comment, and add your >>>> suggestions . >>>> >>>> Detailed proposal: >>>> https://docs.google.com/document/d/1FdjCnFZM1fNtgyb9-v9fU4FwOX4An-pqEwSaJe8RgUg/edit#heading=h.cftjlkb2wh4h >>>> >>>> Github POC: https://github.com/apache/iceberg/pull/9252 >>>> >>>> Regards, >>>> >>>> Rahil Chertara >>>> Amazon EMR & Athena >>>> rcher...@amazon.com >>>> >>>> >>>> >>>> >>>> >>>> >>>> -- >>>> >>>> Ryan Blue >>>> >>>> Tabular >>>> >>>> >>>> >>>> >>>> -- >>>> >>>> Ryan Blue >>>> >>>> Tabular >>>> >>>> >>>> >>>> >>>> -- >>>> >>>> Ryan Blue >>>> >>>> Tabular >>>> >>>> >>>> >>>> >>>> -- >>>> >>>> Ryan Blue >>>> >>>> Tabular >>>> >>>> >>>> >>>> >>>> -- >>>> >>>> Ryan Blue >>>> >>>> Tabular >>>> >>>> >>>> >>>> >>>> -- >>>> >>>> Ryan Blue >>>> >>>> Tabular >>>> >>>> >>>> >>>> >>>> -- >>>> >>>> Ryan Blue >>>> >>>> Tabular >>>> >>>> >>>> >>>> >>>> -- >>>> >>>> Ryan Blue >>>> >>>> Tabular >>>> >>> > > -- > Ryan Blue > Tabular >
