I will let Neil and Matt clarify the details because I believe they understand the overall picture better. However, I would like to emphasize something that motivated this effort and which may be getting lost in the concerns about versioned vs. versionless docs.
The main problem is that some of the guides need major overhauls. There are people like Neil who are interested in making significant contributions to the guides. What is holding them back is that major changes to the web docs can trigger wholesale deranking of our site by Google. Since versioned docs are tied to Spark releases, which are infrequent, that means potentially being nuked in the search rankings for months. Versionless docs allow for rapid iteration on the guides, which can be driven in part by search rankings. In other words, there is a problem chain here that leads to versionless docs: 1. Several guides need major improvements. 2. We cannot make such improvements because a) that would risk site deranking, and b) we are constrained by Spark's release schedule. 3. Versionless guides allow for incremental improvements, which addresses problems 2a and 2b. This is my understanding of the big picture as described to me by Neil and Matt. I defer to them to elaborate on the details, especially in relation to Google site rankings. If this concern is not valid or not that serious, then we can just iterate slowly on the docs with Spark’s existing release schedule and there is less need for versionless docs. Nick > On Jun 10, 2024, at 1:53 PM, Mridul Muralidharan <mri...@gmail.com> wrote: > > > Hi, > > Versioned documentation has the benefit that users can have reasonable > confidence that features, functionality and examples mentioned will work with > that released Spark version. > A versionless guide runs into potential issues with deprecation, behavioral > changes and new features. > > My concern is not just around features highlighting their supported versions, > but examples which reference others features in spark. > > For example, sql differences between hive ql and ansi sql when we flip the > default in 4.0 : we would have 4.x example snippets for some feature (say > UDAF) which would not work for 3.x and vice versa. > > Regards, > Mridul > > > On Mon, Jun 10, 2024 at 12:03 PM Hyukjin Kwon <gurwls...@apache.org > <mailto:gurwls...@apache.org>> wrote: >> I am +1 on this but as you guys mentioned, we should really be clear on how >> to address different versions. >> >> On Wed, 5 Jun 2024 at 18:27, Matthew Powers <matthewkevinpow...@gmail.com >> <mailto:matthewkevinpow...@gmail.com>> wrote: >>> I am a huge fan of the Apache Spark docs and I regularly look at the >>> analytics on this page >>> <https://analytics.apache.org/index.php?module=CoreHome&action=index&date=yesterday&period=day&idSite=40#?period=day&date=yesterday&category=Dashboard_Dashboard&subcategory=1> >>> to see how well they are doing. Great work to everyone that's contributed >>> to the docs over the years. >>> >>> We've been chipping away with some improvements over the past year and have >>> made good progress. For example, lots of the pages were missing canonical >>> links. Canonical links are a special type of link that are extremely >>> important for any site that has duplicate content. Versioned documentation >>> sites have lots of duplicate pages, so getting these canonical links added >>> was important. It wasn't really easy to make this change though. >>> >>> The current site is confusing Google a bit. If you do a "spark rocksdb" >>> Google search for example, you get the Spark 3.2 Structured Streaming >>> Programming Guide as the first result (because Google isn't properly >>> indexing the docs). You need to Control+F and search for "rocksdb" to >>> navigate to the relevant section which says: "As of Spark 3.2, we add a new >>> built-in state store implementation...", which is what you'd expect in a >>> versionless docs site in any case. >>> >>> There are two different user experiences: >>> >>> * Option A: push Spark 3.1 Structured Streaming users to the Spark 3.1 >>> Structured Streaming Programming guide that doesn't mention RocksDB >>> * Option B: push Spark Structured Streaming users to the latest Structure >>> Streaming Programming guide, which mentions RocksDB, but caveat that this >>> feature was added in Spark 3.2 >>> >>> I think Option B provides Spark 3.1 users a better experience overall. >>> It's better to let users know they can access RocksDB by upgrading than >>> hiding this info from them IMO. >>> >>> Now if we want Option A, then we'd need to give users a reasonable way to >>> actually navigate to the Spark 3.1 docs. From what I can tell, the only >>> way to navigate from the latest Structured Streaming Programming Guide >>> <https://spark.apache.org/docs/latest/structured-streaming-programming-guide.html> >>> to a different version is by manually updating the URL. >>> >>> I was just skimming over the Structured Streaming Programming guide and >>> noticing again how lots of the Python code snippets aren't PEP 8 compliant. >>> It seems like our current docs publishing process would prevent us from >>> improving the old docs pages. >>> >>> In this conversation, let's make sure we distinguish between "programming >>> guides" and "API documentation". API docs should be versioned and there is >>> no question there. Programming guides are higher level conceptual >>> overviews, like the Polars user guide <https://docs.pola.rs/>, and should >>> be relevant across many versions. >>> >>> I would also like to point out the the current programming guides are not >>> consistent: >>> >>> * The Structured Streaming programming guide >>> <https://spark.apache.org/docs/latest/structured-streaming-programming-guide.html> >>> is one giant page >>> * The SQL programming guide >>> <https://spark.apache.org/docs/latest/sql-programming-guide.html> is split >>> on many pages >>> * The PySpark programming guide >>> <https://spark.apache.org/docs/latest/api/python/getting_started/index.html> >>> takes you to a whole different URL structure and makes it so you can't >>> even navigate to the other programming guides anymore >>> >>> I am looking forward to collaborating with the community and improving the >>> docs to 1. delight existing users and 2. attract new users. Docs are a >>> "website problem" and we're big data people, but I'm confident we'll be >>> able to work together and find a good path forward here. >>> >>> >>> On Wed, Jun 5, 2024 at 3:22 PM Neil Ramaswamy <n...@ramaswamy.org >>> <mailto:n...@ramaswamy.org>> wrote: >>>> Thanks all for the responses. Let me try to address everything. >>>> >>>> > the programming guides are also different between versions since >>>> > features are being added, configs are being added/ removed/ changed, >>>> > defaults are being changed etc. >>>> >>>> I agree that this is the case. But I think it's fine to mention what >>>> version a feature is available in. In fact, I would argue that mentioning >>>> an improvement that a version brings motivates users to upgrade more than >>>> keeping docs improvement to "new releases to keep the community updating". >>>> Users should upgrade to get a better Spark, not better Spark documentation. >>>> >>>> > having a programming guide that refers to features or API methods that >>>> > does not exist in that version is confusing and detrimental >>>> >>>> I don't think that we'd do this. Again, programming guides should teach >>>> fundamentals that do not change version-to-version. TypeScript >>>> <https://www.typescriptlang.org/docs/handbook/typescript-from-scratch.html> >>>> (which has one of the best DX's and docs) does this exceptionally well. >>>> Their guides are refined, versionless pages, new features are elaborated >>>> upon in release notes (analogous to our version-specific docs), and for >>>> the occasional caveat for a version, it is called out in the guides. >>>> >>>> I agree with Wenchen's 3 points. I don't think we need to say that they >>>> have to go to the old page, but that if they want to, they can. >>>> >>>> Neil >>>> >>>> On Wed, Jun 5, 2024 at 12:04 PM Wenchen Fan <cloud0...@gmail.com >>>> <mailto:cloud0...@gmail.com>> wrote: >>>>> I agree with the idea of a versionless programming guide. But one thing >>>>> we need to make sure of is we give clear messages for things that are >>>>> only available in a new version. My proposal is: >>>>> keep the old versions' programming guide unchanged. For example, people >>>>> can still access https://spark.apache.org/docs/3.3.4/quick-start.html >>>>> In the new versionless programming guide, we mention at the beginning >>>>> that for Spark versions before 4.0, go to the versioned doc site to read >>>>> the programming guide. >>>>> Revisit the programming guide of Spark 4.0 (compare it with the one of >>>>> 3.5), and adjust the content to mention version-specific changes (API >>>>> change, new features, etc.) >>>>> Then we can have a versionless programming guide starting from Spark 4.0. >>>>> We can also revisit programming guides of all versions and combine them >>>>> into one with version-specific notes, but that's probably too much work. >>>>> >>>>> Any thoughts? >>>>> >>>>> Wenchen >>>>> >>>>> On Wed, Jun 5, 2024 at 1:39 AM Martin Andersson >>>>> <martin.anders...@kambi.com <mailto:martin.anders...@kambi.com>> wrote: >>>>>> While I have no practical knowledge of how documentation is maintained >>>>>> in the spark project, I must agree with Nimrod. For users on older >>>>>> versions, having a programming guide that refers to features or API >>>>>> methods that does not exist in that version is confusing and detrimental. >>>>>> >>>>>> Surely there must be a better way to allow updating documentation more >>>>>> often? >>>>>> >>>>>> Best Regards, >>>>>> Martin >>>>>> >>>>>> From: Nimrod Ofek <ofek.nim...@gmail.com <mailto:ofek.nim...@gmail.com>> >>>>>> Sent: Wednesday, June 5, 2024 08:26 >>>>>> To: Neil Ramaswamy <n...@ramaswamy.org <mailto:n...@ramaswamy.org>> >>>>>> Cc: Praveen Gattu <praveen.ga...@databricks.com.invalid>; dev >>>>>> <dev@spark.apache.org <mailto:dev@spark.apache.org>> >>>>>> Subject: Re: [DISCUSS] Versionless Spark Programming Guide Proposal >>>>>> >>>>>> >>>>>> EXTERNAL SENDER. Do not click links or open attachments unless you >>>>>> recognize the sender and know the content is safe. DO NOT provide your >>>>>> username or password. >>>>>> >>>>>> >>>>>> Hi Neil, >>>>>> >>>>>> >>>>>> While you wrote you don't mean the api docs (of course), the programming >>>>>> guides are also different between versions since features are being >>>>>> added, configs are being added/ removed/ changed, defaults are being >>>>>> changed etc. >>>>>> >>>>>> I know of "backport hell" - which is why I wrote that once a version is >>>>>> released it's freezed and the documentation will be updated for the new >>>>>> version only. >>>>>> >>>>>> I think of it as facing forward and keeping older versions but focusing >>>>>> on the new releases to keep the community updating. >>>>>> While spark has support window of 18 months until eol, we can have only >>>>>> 6 months support cycle until eol for documentation- there are no major >>>>>> security concerns for documentation... >>>>>> >>>>>> Nimrod >>>>>> >>>>>> בתאריך יום ד׳, 5 ביוני 2024, 08:28, מאת Neil Ramaswamy >>>>>> <n...@ramaswamy.org <mailto:n...@ramaswamy.org>>: >>>>>> Hi Nimrod, >>>>>> >>>>>> Quick clarification—my proposal will not touch API-specific >>>>>> documentation for the specific reasons you mentioned (signatures, >>>>>> behavior, etc.). It just aims to make the programming guides >>>>>> versionless. Programming guides should teach fundamentals of Spark, and >>>>>> the fundamentals of Spark should not change between releases. >>>>>> >>>>>> There are a few issues with updating documentation multiple times after >>>>>> Spark releases. First, fixes that apply to all existing versions' >>>>>> programming guides need backport PRs. For example, this change >>>>>> <https://github.com/apache/spark/pull/46797/files> applies to all the >>>>>> versions of the SS programming guide, but is likely to be fixed only in >>>>>> Spark 4.0. Additionally, any such update within a Spark release will >>>>>> require re-building the static sites in the spark repo, and copying >>>>>> those files to spark-website via a commit in spark-website. Making a >>>>>> typo fix like the one I linked would then require <number of versions we >>>>>> want to update> + 1 PRs, opposed to 1 PR in the versionless programming >>>>>> guide world. >>>>>> >>>>>> Neil >>>>>> >>>>>> On Tue, Jun 4, 2024 at 1:32 PM Nimrod Ofek <ofek.nim...@gmail.com >>>>>> <mailto:ofek.nim...@gmail.com>> wrote: >>>>>> Hi, >>>>>> >>>>>> While I think that the documentation needs a lot of improvement and >>>>>> important details are missing - and detaching the documentation from the >>>>>> main project can help iterating faster on documentation specific tasks, >>>>>> I don't think we can nor should move to versionless documentation. >>>>>> >>>>>> Documentation is version specific: parameters are added and removed, new >>>>>> features are added, behaviours sometimes change etc. >>>>>> >>>>>> I think the documentation should be version specific- but separate from >>>>>> spark release cadence - and can be updated multiple times after spark >>>>>> release. >>>>>> The way I see it is that the documentation should be updated only for >>>>>> the latest version and some time before a new release should be archived >>>>>> and the updated documentation should reflect the new version. >>>>>> >>>>>> Thanks, >>>>>> Nimrod >>>>>> >>>>>> בתאריך יום ג׳, 4 ביוני 2024, 18:34, מאת Praveen Gattu >>>>>> <praveen.ga...@databricks.com.invalid>: >>>>>> +1. This helps for greater velocity in improving docs. However, we might >>>>>> still need a way to provide version specific information isn't it, i.e. >>>>>> what features are available in which version etc. >>>>>> >>>>>> On Mon, Jun 3, 2024 at 3:08 PM Neil Ramaswamy <n...@ramaswamy.org >>>>>> <mailto:n...@ramaswamy.org>> wrote: >>>>>> Hi all, >>>>>> >>>>>> I've written up a proposal to migrate all the Apache Spark programming >>>>>> guides to be versionless. You can find the proposal here >>>>>> <https://docs.google.com/document/d/1OqeQ71zZleUa1XRZrtaPDFnJ-gVJdGM80o42yJVg9zg/>. >>>>>> Please leave comments, or reply in this DISCUSS thread. >>>>>> >>>>>> TLDR: by making the programming guides versionless, we can make updates >>>>>> to them whenever we'd like, instead of at the Spark release cadence. >>>>>> This increased update velocity will enable us to make gradual >>>>>> improvements, including breaking up the Structured Streaming programming >>>>>> guide into smaller sub-guides. The proposal does not break any existing >>>>>> URLs, and it does not affect our versioned API docs in any way. >>>>>> >>>>>> Thanks! >>>>>> Neil >>>>>> CONFIDENTIALITY NOTICE: This email message (and any attachment) is >>>>>> intended only for the individual or entity to which it is addressed. The >>>>>> information in this email is confidential and may contain information >>>>>> that is legally privileged or exempt from disclosure under applicable >>>>>> law. If you are not the intended recipient, you are strictly prohibited >>>>>> from reading, using, publishing or disseminating such information and >>>>>> upon receipt, must permanently delete the original and destroy any >>>>>> copies. We take steps to protect against viruses and other defects but >>>>>> advise you to carry out your own checks and precautions as Kambi does >>>>>> not accept any liability for any which remain. Thank you for your >>>>>> co-operation.
