Some pages unavailable due to PostconditionException: makeTitleSafe() should always return a Title
Closed, ResolvedPublicPRODUCTION ERROR
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Description

Error

mwversion: 1.37.0-wmf.21
reqId: 795cc792-1a06-408b-82ea-f42d42cf91b7
Find reqId in Logstash
Find normalized_message in Logstash

normalized_message

[{reqId}] {exception_url}   Wikimedia\Assert\PostconditionException: Postcondition failed: makeTitleSafe() should always return a Title for the text returned by getRootText().

Variation for getBaseText():

Wikimedia\Assert\PostconditionException: Postcondition failed: makeTitleSafe() should always return a Title for the text returned by getBaseText().

exception.trace

from /srv/mediawiki/php-1.37.0-wmf.21/vendor/wikimedia/assert/src/Assert.php(202)
#0 /srv/mediawiki/php-1.37.0-wmf.21/includes/Title.php(2053): Wikimedia\Assert\Assert::postcondition(boolean, string)
#1 /srv/mediawiki/php-1.37.0-wmf.21/includes/skins/Skin.php(518): Title->getRootTitle()
#2 /srv/mediawiki/php-1.37.0-wmf.21/skins/MinervaNeue/includes/Skins/SkinMinerva.php(241): Skin->getPageClasses(Title)
#3 /srv/mediawiki/php-1.37.0-wmf.21/includes/OutputPage.php(3147): SkinMinerva->getPageClasses(Title)
#4 /srv/mediawiki/php-1.37.0-wmf.21/includes/skins/SkinTemplate.php(440): OutputPage->headElement(SkinMinerva)
#5 /srv/mediawiki/php-1.37.0-wmf.21/skins/MinervaNeue/includes/Skins/SkinMinerva.php(125): SkinTemplate->prepareQuickTemplate()
#6 /srv/mediawiki/php-1.37.0-wmf.21/skins/MinervaNeue/includes/Skins/SkinMinerva.php(78): SkinMinerva->prepareQuickTemplate()
#7 /srv/mediawiki/php-1.37.0-wmf.21/includes/skins/SkinMustache.php(56): SkinMinerva->getTemplateData()
#8 /srv/mediawiki/php-1.37.0-wmf.21/includes/skins/SkinTemplate.php(150): SkinMustache->generateHTML()
#9 /srv/mediawiki/php-1.37.0-wmf.21/includes/OutputPage.php(2644): SkinTemplate->outputPage()
#10 /srv/mediawiki/php-1.37.0-wmf.21/includes/MediaWiki.php(939): OutputPage->output(boolean)
#11 /srv/mediawiki/php-1.37.0-wmf.21/includes/MediaWiki.php(952): MediaWiki::{closure}()
#12 /srv/mediawiki/php-1.37.0-wmf.21/includes/MediaWiki.php(559): MediaWiki->main()
#13 /srv/mediawiki/php-1.37.0-wmf.21/index.php(53): MediaWiki->run()
#14 /srv/mediawiki/php-1.37.0-wmf.21/index.php(46): wfIndexMain()
#15 /srv/mediawiki/w/index.php(3): require(string)
#16 {main}

Impact

Notes

Easily reproducible via the (redacted) url -- seems like unexpected/unhandled user input

Details

Request URL: https://www.mediawiki.org/wiki/*/*

	Subject	Repo	Branch	Lines +/-
	Title: be more robust when handling invalid titles	mediawiki/core	master	+50 -8
	skins: Change Skin::getPageClasses to avoid Title::getRootTitle	mediawiki/core	master	+7 -5

Customize query in gerrit

Related Objects

Mentioned In: T350630: Wikimedia\Assert\PostconditionException: Postcondition failed: makeTitleSafe() should always return a Title for the text returned by getRootText()
Mentioned Here: T145328: Activation of WikidataPageBanner extension on Italian Wikivoyage
T298315: Deleting Ns:104 in it:voy
T296131: Talk page loading error: Postcondition failed: makeTitleSafe() should always return a Title for the text returned by getRootText().
T225585: Unable to open user sub pages with trailing space (Blank page fatal: "invalid DB key")

Event Timeline

thcipriani created this task.Sep 1 2021, 6:43 PM

Restricted Application added subscribers: Masumrezarock100, Aklapper. · View Herald TranscriptSep 1 2021, 6:43 PM

Tagged @Jdlrobson specifically because phab didn't complete a likely looking team tag for #reading -- what the tag I should be using?

thcipriani moved this task from Untriaged to Sep 2021 on the Wikimedia-production-error board.Sep 1 2021, 6:48 PM

Will investigate soon! Thanks for the report!

Jdlrobson moved this task from Backlog to Simplify Minerva on the Web-Team-Backlog (Needs Prioritization (Tech)) board.Sep 2 2021, 1:16 AM

Looks like this also applies to the Vector skin so it's an issue in mediawiki core.

Jdlrobson triaged this task as Medium priority.Sep 2 2021, 7:24 PM

Jdlrobson removed a project: Reading-Admin.

Jdlrobson moved this task from Backlog to Milestone: More flexibility in article heading area (subpages, descriptions) on the MediaWiki-Core-Skin-Architecture board.Sep 3 2021, 7:29 PM

Jdlrobson moved this task from Milestone: More flexibility in article heading area (subpages, descriptions) to 1.37 release on the MediaWiki-Core-Skin-Architecture board.

? Looking closely, it doesn't seem like an issue in the skin code but inside the Title or OutputPage code which are out of the scope of my team (not sure of appropriate tag).... @Pchelolo perhaps you have an idea of what is happening here or maybe someone in platform engineering/traffic?

There are only 3 instances of this error in the last 7 days and it only seems to be impacting mediawiki.org and it's impacting both desktop and mobile site.

Maintenance_bot added a project: SRE.Sep 3 2021, 7:45 PM

The assertion was added for T225585

It is possible to get the page name or a non-redacted url? If there is a problem with something in the url: it is possible to create a fake one which fatals by replacing some letters?

It is hard to tell without example, why a title fails normalization when everything behind the first / is removed.

In T290194#7451977, @Umherirrender wrote:

It is possible to get the page name or a non-redacted url? If there is a problem with something in the url: it is possible to create a fake one which fatals by replacing some letters?

It is hard to tell without example, why a title fails normalization when everything behind the first / is removed.

You can find a link in the task description of the duplicate task.

In T290194#7518495, @Zabe wrote:

In T290194#7451977, @Umherirrender wrote:

It is possible to get the page name or a non-redacted url? If there is a problem with something in the url: it is possible to create a fake one which fatals by replacing some letters?

It is hard to tell without example, why a title fails normalization when everything behind the first / is removed.

You can find a link in the task description of the duplicate task.

That is a namespace issue due to (bad) config and missing cleanup after config change.

https://bn.wikibooks.org/w/api.php?action=query&titles=%E0%A6%86%E0%A6%B2%E0%A6%BE%E0%A6%AA:%E0%A6%B0%E0%A6%A8%E0%A7%8D%E0%A6%A7%E0%A6%A8%E0%A6%AA%E0%A7%8D%E0%A6%B0%E0%A6%A3%E0%A6%BE%E0%A6%B2%E0%A7%80:%E0%A6%A1%E0%A6%BF%E0%A6%AE%20%E0%A6%AD%E0%A6%BE%E0%A6%9C%E0%A6%BF

The requested page title refers to a talk page that cannot exist.

Change 740315 had a related patch set uploaded (by Umherirrender; author: Umherirrender):

[mediawiki/core@master] Replace Title::getRootTitle with TitleFormatter in Skin::getPageClasses

https://gerrit.wikimedia.org/r/740315

gerritbot added a project: Patch-For-Review.Nov 20 2021, 10:17 PM

There is no way to avoid this exception, because the invalid title is already there. Just avoid the title object to avoid the bad title which throws the exception here.

In a perfect world this is not needed, but due to config changes there are situation where this can happen for short or long periodes.

@Umherirrender Is it possible to delete the two pages I mentioned (T296131) from the server side?

In T290194#7518611, @MdsShakil wrote:

@Umherirrender Is it possible to delete the two pages I mentioned (T296131) from the server side?

It is not possible to delete them normally with the wiki UI. api.php can handle pages by pageid and it could be possible to move the page (without redirect by sysop) or to delete the page (by sysop) with Special:ApiSandbox or by direct api calls.
The other solutation is to request a run of namespaceDupes.php for that wiki to fix it from the server side and delete it afterwards.

I trying to delete two pages using python script as instructed here, but results was failed (called two pages was not exist). I have no idea how to use mw api

In T290194#7520866, @MdsShakil wrote:

I trying to delete two pages using python script as instructed here, but results was failed (called two pages was not exist). I have no idea how to use mw api

You can try

Press "make request" and fill in the "token" by pressing "correct token and submit". That would also use the api. If you want use the python you have to replace 'title':"enter_a_page_title" with 'pageid': <number> and put in the number of curid on the url. The reason in the link is Page not reachable - [[phab:T296131]], but could be changed as needed.

Done. Logid 20399 & 20398.

Legoktm removed projects: SRE, Traffic.Nov 22 2021, 10:48 PM

MdsShakil unsubscribed.Nov 29 2021, 5:39 PM

Still seen. E.g. https://it.wikivoyage.org/w/index.php?title=Tematica:Destinazioni&oldid=712466.

Krinkle renamed this task from Wikimedia\Assert\PostconditionException: Postcondition failed: makeTitleSafe() should always return a Title for the text returned by getRootText(). to Some pages unavailable due to PostconditionException: makeTitleSafe() should always return a Title.Mar 15 2022, 12:35 AM

Krinkle updated the task description. (Show Details)

Change 740315 merged by jenkins-bot:

[mediawiki/core@master] skins: Change Skin::getPageClasses to avoid Title::getRootTitle

https://gerrit.wikimedia.org/r/740315

Maintenance_bot removed a project: Patch-For-Review.Apr 13 2022, 12:30 AM

ReleaseTaggerBot added a project: MW-1.39-notes (1.39.0-wmf.8; 2022-04-18).Apr 13 2022, 1:00 AM

In T290194#7776230, @Krinkle wrote:

Still seen. E.g. https://it.wikivoyage.org/w/index.php?title=Tematica:Destinazioni&oldid=712466.

Still fails after the patch is deployed. But it shows the error handling of mediawiki and not the white error page of Wikimedia. That means the skin building code now passed, but something other still calls function which fails.

Would be nice to see the next stacktrace

[dee62ec0-7073-4021-a2d3-2e1e46e967f8] 2022-04-20 18:05:11: Errore irreversibile di tipo "Wikimedia\Assert\PostconditionException"

class includes now page-Speciale_Badtitle_NS104_Destinazioni rootpage-Speciale_Badtitle_NS104_Destinazioni

Zabe merged a task: T312056: Unable to access page 82496 on viwiki.Jul 5 2022, 7:40 AM

Zabe added subscribers: NguoiDungKhongDinhDanh, • Familyfirst407.

Umherirrender unsubscribed.Feb 10 2023, 7:51 PM

In T290194#7776230, @Krinkle wrote:

Still seen. E.g. https://it.wikivoyage.org/w/index.php?title=Tematica:Destinazioni&oldid=712466.

These revisions have been broken for two years now.

In T290194#7395374, @Umherirrender wrote:

The assertion was added for T225585

Indeed, introduced in:

In T225585#5298106, @gerritbot wrote:

Change 517014 merged by jenkins-bot:
[mediawiki/core@master] Title: ensure getBaseTitle and getRootTitle return valid Titles

https://gerrit.wikimedia.org/r/517014

/cc @daniel @BPirkle. Tagging API Platform for ease of discovery (ince you both moved to that team, and Title.php isn't explicitly part of any component).

Umherirrender unsubscribed.Oct 7 2023, 9:53 PM

Umherirrender mentioned this in T350630: Wikimedia\Assert\PostconditionException: Postcondition failed: makeTitleSafe() should always return a Title for the text returned by getRootText().Nov 6 2023, 11:05 PM

matmarex merged a task: T350630: Wikimedia\Assert\PostconditionException: Postcondition failed: makeTitleSafe() should always return a Title for the text returned by getRootText().Nov 7 2023, 1:00 AM

matmarex added subscribers: matmarex, Umherirrender.

Umherirrender unsubscribed.Nov 29 2023, 10:18 PM

Aforementioned URLs are broken with a Fatal Error on each page view. This is a regression from the Title factor carried out by the former Core Platform Team (led by @daniel at the time, I believe).

While reported the inbox of several incarnations of CPT and later API Platform, the regression remains untriaged (much less fixed). Tagging MediaWiki-Engineering group for fallback triage.

Krinkle moved this task from Sep 2021 to Older on the Wikimedia-production-error board.Feb 22 2024, 8:13 PM

In T290194#7518504, @Umherirrender wrote:

That is a namespace issue due to (bad) config and missing cleanup after config change.

Correct. This happens when a revision ID is given that points to a revision that belongs to a page that is in a namespace that doesn't exist anymore. E.g. https://it.wikivoyage.org/w/index.php?title=Dummy&oldid=712466 is in namespace 104 which was removed two weeks ago, see r952817 and T298315 and T145328.

There are 226 pages left in that namespace, all redirects. We should probably have a script for mass-deleting pages like this. There is a nother ticket somewhere with the same root cause that I investigated a couple of weeks ago.

Change 1006053 had a related patch set uploaded (by Daniel Kinzler; author: Daniel Kinzler):

[mediawiki/core@master] Title: be more robust when handling invalid titles

https://gerrit.wikimedia.org/r/1006053

gerritbot added a project: Patch-For-Review.Feb 23 2024, 6:19 PM

We should perhaps also think about how we could be more lenient. Invalid namespaces are always bound to cause problems, but we could avoid this specific issue easily enough. See the patch I just posted.

Change 1006053 merged by jenkins-bot:

[mediawiki/core@master] Title: be more robust when handling invalid titles

https://gerrit.wikimedia.org/r/1006053

Maintenance_bot removed a project: Patch-For-Review.Feb 26 2024, 4:30 PM

ReleaseTaggerBot added a project: MW-1.42-notes (1.42.0-wmf.20; 2024-02-27).Feb 26 2024, 5:00 PM

MSantos moved this task from Inbox, needs triage to MediaWiki Interfaces team on the MediaWiki-Engineering board.Feb 28 2024, 12:34 PM

In T290194#7869110, @Umherirrender wrote:

In T290194#7776230, @Krinkle wrote:

Still seen. E.g. https://it.wikivoyage.org/w/index.php?title=Tematica:Destinazioni&oldid=712466.

Still fails after the patch is deployed. But it shows the error handling of mediawiki and not the white error page of Wikimedia. That means the skin building code now passed, but something other still calls function which fails.

The page is now accessible with title Speciale:Badtitle/NS104:Destinazioni, that is another issue. The fatal is gone, task is resolved.

Some pages unavailable due to PostconditionException: makeTitleSafe() should always return a TitleClosed, ResolvedPublicPRODUCTION ERRORActions