Allow compatibility with `ext-mongodb` version 2.0

Hi @yurii. Have you already taken a look at what that would involve ?

The ext-mongodb 2.0.0 announcement documents incompatible changes in the extension API, dropping support for PHP 8.0 (no big deal, Drupal ≥ 10 already requires 8.1), and requiring mongodb/mongodb 2.0.0.

The mongodb/mongodb 2.0.0 announcement is not as explicitly incompatible but still warns about many changes.

MongDB 4.x support is also dropped, but I do not think this is a big deal these days.

I'm going to review the release notes and see if there's any obvious flags. I will also start an issue fork so we can loosen the version restraint to allow v2 to install and perform testing.

I've opened an MR, which allows ext-mongodb 2.x and mongodb/mongodb 2.x alongside the existing 1.x support.

Changes

• Widened the constraints in the root and all submodule composer.json files to "ext-mongodb": "^1.5.1 || ^2.0" and "mongodb/mongodb": "^1.13 || ^2.0". Composer picks the library version that matches the installed extension.
• Updated docs/install.md to say the 2.x extension is supported.

The one breaking change

I reviewed the module against the 2.0 upgrade guides for both the library and the extension. Only one change affects the module: the 2.0 library removed MongoDB\Model\CollectionInfoIterator, and Database::listCollections() now returns a plain Iterator.

Logger::eventCollections() in mongodb_watchdog declared CollectionInfoIterator as its return type, so it would fail on 2.x. I changed the return type to \Iterator. In 1.x, CollectionInfoIterator extends Iterator, so this works on both versions. CollectionInfoIterator adds no methods of its own, so callers that only iterate the result are not affected.

Nothing else from the upgrade guides affects the module. It doesn't use the return values of methods that now return void (drop(), createCollection()), and its bsonUnserialize() methods already declare : void. It also doesn't use mapReduce(), the removed BSON functions, integer ReadPreference modes, or the removed query and driver options.

Testing

Composer resolves mongodb/mongodb 2.4.2 against ext-mongodb 2.5.2 and can still pick the 1.x library with the 1.x extension. CI should now run the 2.x library with the 2.x extension; it previously ran the 1.x library with the 2.x extension, because pecl install mongodb installs 2.x. Manual testing with the 1.x extension and library would still be welcome.

Setting to Needs review.

The first pipeline didn't really test 2.x: pecl install mongodb failed because the CI image lacks autoconf, so the extension never got installed. I've updated .gitlab-ci.yml to install the build tools and to fail the job if the extension doesn't load.

The failures in ControllerTest (drupal_rewrite_settings()) and FormStateValueResolver (ArgumentValueResolverInterface) are unrelated Drupal 11 issues and should have a separate follow-up for them.

With the CI fix, the kernel tests now run against ext-mongodb 2.5.3 and mongodb/mongodb 2.x, and all tests that talk to MongoDB pass. The remaining failures (drupal_rewrite_settings(), ArgumentValueResolverInterface, the QueueTest constructor, non-static data providers) are existing Drupal 11 / PHPUnit 10 issues, unrelated to this change.

Moving this to postponed and draft until MR51 merges. Then will need to adjust this MR a little before it's ready again.

I tested this MR combined with the one from #3625939: Fix Drupal 11 / Symfony 7 compatibility errors and failing CI jobs, since the branch alone still hits the Drupal 11 breakages that one fixes. Setup: Drupal 11.4.8, PHP 8.5.11, ext-mongodb 2.5.3, mongodb/mongodb 2.4.2, MongoDB 8.3, with this MR's composer.json changes applied on top of the #3625939: Fix Drupal 11 / Symfony 7 compatibility errors and failing CI jobs branch.

• Result: 50 tests, 207 assertions, 1 error. Every test that talks to MongoDB passes with the 2.x driver.
• The one error is Functional ControllerTest::testLoggerReportsAccess: on PHP 8.5, the implicitly nullable $eventTemplate in DetailController::getTop() fails the test, where PHP 8.4 only reported it. That is #3458044: [PHP 8.4] Fix implicitly nullable type declarations.
• PHP 8.5 also deprecates ReflectionMethod::setAccessible(), used in QueueTest.php line 176. It has had no effect since PHP 8.1, so the line can simply go.
• The 1.x extension does not build on PHP 8.5: mongodb-1.21.10 fails on IS_INTERNED, which PHP 8.5 removed. Among the extension's releases, only 2.1.2 and later announce PHP 8.5 support. Since Drupal 12 requires PHP 8.5, this issue is a prerequisite for Drupal 12.

Once #3625939: Fix Drupal 11 / Symfony 7 compatibility errors and failing CI jobs is merged, please rebase and reduce this MR to what is specific to 2.x:

• Drop the Logger::eventCollections() change: #3625939: Fix Drupal 11 / Symfony 7 compatibility errors and failing CI jobs makes the same one.
• Drop the CI build-tools block, per the review in #3625939: Fix Drupal 11 / Symfony 7 compatibility errors and failing CI jobs.
• Constraints: widen the floors #3625939: Fix Drupal 11 / Symfony 7 compatibility errors and failing CI jobs sets instead of the current ones, e.g. "ext-mongodb": "^1.21 || ^2.4" and "mongodb/mongodb": "^1.21 || ^2.4" in all four composer.json. Library 2.4.2 requires ext-mongodb ^2.4, and these are the versions tested above.
• docs/install.md has been rewritten in #3626482: Update docs site for 2026-09, so the 2.x wording needs redoing on top of it: 8.x-2.x supports extension and library 1.21 or later, or 2.4 or later, and PHP 8.5 needs 2.x.
• CI has to test each extension with its own library. With --ignore-platform-req=ext-mongodb, Composer ignores the installed extension, so once 2.x is allowed it installs library 2.x even in jobs that run the 1.x extension. Installing the extension in the composer jobs too and dropping that flag lets Composer pick the matching library in each variant: 1.x with the pinned 1.21.10 on the current and previous cores, 2.x on the next major, where PHP 8.5 rules out 1.x.

Mostly good, I added a few fixes, mostly around docs and the build.

Build only fails on #3458044: [PHP 8.4] Fix implicitly nullable type declarations, which I'll merge first.

Merged to today's HEAD, thanks.

Yeah so cool!!! Nice @fgm!!!