Hey everyone! 👋 I've been diving deep into SonarQube for our team's code quality, and it's been great for the standard stuff. But we have a bunch of internal API patterns and conventions (think specific naming for endpoints, mandatory response headers, versioning in the URL path) that the default rules don't catch.
I want to create custom rules to flag deviations from our internal API style, but I'm finding the jump from using built-in rules to writing my own a bit steep. I've poked around the documentation, but a practical guide from someone who's done it would be super helpful.
Could someone walk me through the essentials? Specifically:
* What's the most straightforward way to start? Are we talking writing a custom plugin in Java, or can we leverage something like the "Custom Rules" feature for specific languages?
* For Java-based APIs (Spring Boot), what's the best approach? I'm assuming we'd be analyzing the AST?
* How do you handle the deployment and maintenance of these custom rules across the team? Does everyone need the plugin, or is there a central repository method?
I'm not afraid of a little config work—I spend my days comparing MA platform workflows, after all!—but I want to make sure I'm setting off down the right path before I invest a bunch of time. Any gotchas or "I wish I'd known" tips would be awesome.
Pick the right stack.
MartechMatch
For Java with Spring Boot, you're correct that you'll be analyzing the AST. The straightforward path is using the SonarJava Custom Rules API. You extend `IssuableSubscriptionVisitor` to subscribe to specific AST node types, like `MethodTree` for endpoint methods, then inspect annotations like `@RequestMapping` and the method name. The real challenge is modeling your team's conventions as deterministic logic; pattern matching on strings gets messy quickly.
On deployment, everyone needs the plugin. You package your rules into a JAR and deploy it to your SonarQube server instance. It's a centralized install, so individual developers don't need it locally. Maintenance becomes a CI/CD artifact itself; version your plugin and treat updates like any other library dependency to avoid breaking scans.
For your initial question about leveraging the "Custom Rules" feature, that's typically for languages where you can define rules with XPath or similar within the UI. For complex API pattern validation in Java, you're almost always in plugin territory. Start with one concrete rule, like enforcing a URL path prefix, to get the toolchain working before tackling mandatory headers.
you can't fix what you don't measure