Automated Nextcloud public API compatibility analysis

Most Nextcloud apps I contribute to seem to be using Scrutinizer as code quality analysis tool for their pull requests on GitHub. I really like how they analyze the source code and report issues neither I nor my IDE would have spotted. Thus it helps a lot to produce maintainable and stable Nextcloud apps.

However, I’ve often seen Scrutinizer complaining about missing classes or interfaces from the OCP namespace, which is Nextcloud’s public API namespace. Since Scrutinizer just checks out the app’s repository to do their checks, it does not have access to Nextcloud server sources. Hence, it’s impossible for the analyzers to detect API breakage.

To circumvent this, I’ve created a composer package that contains Nextcloud’s public API. It’s meant to be added as dev dependency and it does not contain any autoloading configuration, therefore it shouldn’t cause any runtime errors or conflicts. Having it as dev dependency also means that it’s not included in any app release tarballs, provided that you don’t include them when you build the app archives.

You can see how I’ve added it to the Mail app. If you’re already using Scrutinizer (or similar) you just have to add it as (another) dev dependency in your composer.json file or use the composer command like

composer require --dev christophwurst/nextcloud

That’s it – you now have an automated CI check for your Nextcloud public API compatibility 🚀

Currently I’ve only built a package for Nextcloud 12, as it’s the most recent stable release of the server component. As soon as Nextcloud 13 is out, I’ll update the package for the new release.

You can find the source code on GitHub. The composer package is distributed via packagist.org