I'd like to see third party users, even those not on the mailing list, get advance notice in one release (say in the release notes) so that when the next release shows up with the deprecated code removed, they have had time to patch up any internal extensions and code they may have.
I don't want to penalize third parties who may not publish their extensions because they think the code is not good enough for public consumption or because it is very specific to their company or workflow. I also don't want to encourage delays in updating, or the common practice of running very outdated versions of MediaWiki. Of course some folks will remain on LTS; that's what it's there for. But once a new release is out, we should want parties to be in a position to update to it immediately, at least as far as our processes go. A delay of two releases is nice but not necessary and honestly I'd just skip that altogether. Just my .02 €, Ariel On Fri, Aug 28, 2020 at 12:19 PM Daniel Kinzler <[email protected]> wrote: > Hi all! > > Since the new Stable Interface Policy[1] has come into effect, there has > been > some confusion about when and how the deprecation process can be > accelerated or > bypassed. I started a discussion about this issue on the talk page[2], and > now > I'm writing this email in the hope of gathering more perspectives. > > tl;dr: the key question is: > > Can we shorten or even entirely skip the deprecation process, > if we have removed all usages of the obsolete code from public > extensions? > > If you are affected by the answer to this question, or you otherwise have > opinions about it, please read on (ok ok, this mail is massive - at least > read > the proposed new wording of the policy). I'm especially interested in the > opinions of extension developers. > > > So, let's dive in. On the one hand, the new (and old) policy states: > > Code MUST emit hard deprecation notices for at least one major > MediaWiki version before being removed. It is RECOMMENDED to emit > hard deprecation notices for at least two major MediaWiki > versions. EXCEPTIONS to this are listed in the section "Removal > without deprecation" below. > > This means that code that starts to emit a deprecation warning in version > N can > only be removed in version N+1, better even N+2. This effectively > recommends > that obsolete code be kept around for at least half a year, with a > preference > for a full year and more. However, we now have this exception in place: > > The deprecation process may be bypassed for code that is unused > within the MediaWiki ecosystem. The ecosystem is defined to > consist of all actively maintained code residing in repositories > owned by the Wikimedia foundation, and can be searched using the > code search tool. > > When TechCom added this section[3][4], we were thinking of the case where a > method becomes obsolete, but is unused. In that case, why go through all > the > hassle of deprecation, if nobody uses it anyway? > > However, what does this mean for obsolete code that *is* used? Can we just > go > ahead and remove the usages, and then remove the code without deprecation? > That > seems to be the logical consequence. > > The result is a much tighter timeline from soft deprecation to removal, > reducing > the amount of deprecated code we have to drag along and keep functional. > This is > would be helpful particularly when code was refactored to remove > undesirable > dependencies, since the dependency will not actually go away until the > deprecated code has been removed. > > So, if we put in the work to remove usages, can we skip the deprecation > process? > After all, if the code is truly unused, this would not do any harm, right? > And > being able to make breaking changes without the need to wait a year for > them to > become effective would greatly improve the speed at which we can modernize > the > code base. > > However, even skipping soft deprecation and going directly to hard > deprecation > of the construction of the Revision class raised concerns, see for instance > <https://www.mail-archive.com/[email protected]/msg92871.html > >. > > The key concern is that we can only know about usages in repositories in > our > "ecosystem", a concept introduced into the policy by the section quoted > above. I > will go into the implications of this further below. But first, let me > propose a > change to the policy, to clarify when deprecation is or is not needed. > > I propose that the policy should read: > > Obsolete code MAY be removed without deprecation if it is unused (or > appropriately gated) by any code in the MediaWiki ecosystem. Such > removal must be recorded in the release notes as a breaking change > without deprecation, and must be announced on the appropriate > mailing lists. > > Obsolete code that is still used within the ecosystem MAY be > removed if it has been emitting deprecation warnings in AT LEAST > one major version release, and a best effort has been made to > remove any remaining usages in the MediaWiki ecosystem. Obsolete > code SHOULD be removed when it has been emitting deprecation > warnings for two releases, even if it is still used. > > And further: > > The person, team, or organization that deprecates code SHOULD > drive the removal of usages in a timely manner. For code not under > the control of this person, team, or organization, appropriate > changes SHOULD be proposed to the maintainers, and guidance SHOULD > be provided when needed. > > Compared to the old process, this puts more focus on removing usages of > obsolete > code. Previously, we'd often just wait and hope that usages of deprecated > methods would vanish eventually. Which may take a long time, we still have > code > in MediaWiki that was deprecated in 1.24. Of course, every now and then > someone > fixes a bunch of usages of deprecated code, but this is a sporadic > occurrence, > not designed into the process. > > With the change I am proposing, whoever deprecates a function also commits > to > removing usages of it asap. For extension developers, this means that they > will > get patches and support, but they may see their code broken if they do not > follow up. > > > Now, my proposal hinges on the idea that we somehow know all relevant code > that > needs fixing. How can that work? > > When TechCom introduced the idea of the "MediaWiki ecosystem" into the > policy, > our reasoning was that we want to support primarily extension developers > who > contribute their extensions back to the ecosystem, by making them > available to > the public. We found it fair to say that if people develop extensions > solely for > their own use, it is up to them to read the release notes. We do not need > to go > out of our way to protect them from changes to the code base. > > Effectively, with the proposed change to the policy, maintainers of public > extensions will get more support keeping their extensions compatible, while > maintainers of private extensions will receive less consideration. > > It seems desirable and fair to me to allow for "fast track" removal of > obsolete > code, but only if we create a clear process for making an extensions > "official". > How exactly would an extension developer make sure that we know their > extension, > and consider it part of the ecosystem? In practice, "known code" is code > accessible via codesearch[5]. But how does one get an extension into the > codesearch index? There is currently no clear process for this. > > Ideally, it would be sufficient to: > * create a page on mediawiki.org using the {{Extension}} infobox, > * setting the status to "stable" (and maybe "beta"), > * and linking to a public git repository. > > It should be simple enough to create a script that feeds these repos into > codesearch. A quick look at Category:Extensions_by_status category tells > me that > there are about a thousand such extensions. > > > So, my question to you is: do you support the change I am proposing to the > policy? If not, why not? And if you do, why do you think it's helpful? > > > -- daniel > > PS: This proposal has not yet been vetted with TechCom, it's just my > personal > take. It will become an RFC if needed. This is intended to start a > conversation. > > > [1] https://www.mediawiki.org/wiki/Stable_interface_policy > [2] https://www.mediawiki.org/wiki/Topic:Vrwr9aloe6y1bi2v > [3] https://phabricator.wikimedia.org/T193613 > [4] https://phabricator.wikimedia.org/T255803 > [5] https://codesearch.wmcloud.org/search/ > > -- > Daniel Kinzler > Principal Software Engineer, Core Platform > Wikimedia Foundation > > _______________________________________________ > Wikitech-l mailing list > [email protected] > https://lists.wikimedia.org/mailman/listinfo/wikitech-l > _______________________________________________ Wikitech-l mailing list [email protected] https://lists.wikimedia.org/mailman/listinfo/wikitech-l
