Extend programmatic control of `NamedInterface` registration to types (not just packages)

[ghferrari]

Spring Modulith's @NamedInterface annotation is applicable to packages and types.

The currently available method for programmatic registration of NamedInterfaces appears to be primarily intended only to support named interfaces at the package level. Furthermore, all publicly accessible static builder methods on the NamedInterface class take only packages as arguments. There are two other methods which take classes as arguments and which could in principle be used programmatically, but they are both package-private.

I think it would be a good improvement to allow a mechanism for programmatic control of NamedInterfaces on classes. It may be as simple as making the two existing package-private methods public.

[odrotbohm]

What kind of collection mechanism do you envision here? A very broad option would be to expose NamedInterface.of(String, Classes) and expect users to manually process JavaPackage.getClasses(). That'd immediately require users to work with the ArchUnit API, so I wonder if there are common patterns that we could support (naming patterns, annotations, etc.).

[ghferrari]

Thanks for the reply @odrotbohm.

For my own use case, I'd like to be able to register named interfaces from a custom annotation, but there may be other use cases, too.

To get this working for annotations, I suppose there needs to some functionality for iterating over the types/classes in an ApplicationModule and registering named interfaces when an annotation is detected on those types. So it may not be quite as simple as just exposing the type-level NamedInterface builder methods. I'll leave it you to you decide how best to approach this - whether via extending the NamedInterfaces.builder method or via some other way. It would be nice to have an example in the docs about how to do it.

[odrotbohm]

I've pushed an approach that should allow you to build named interfaces like this (in ApplicationModuleDetectionStrategy)

NamedInterfaces detectNamedInterfaces(JavaPackage basePackage, ApplicationModuleInformation information) {

  var namedInterface = NamedInterface.of("someName", basePackage, it -> …); // filter goes last

  return NamedInterfaces.of(NamedInterface.unnamed(), namedInterface);
}

Does that fit your bill?