Support for org.apache.cxf.jaxrs.ext.multipart

[languitar]

Is there any reason why the resteasy REST client uses its own data types for multipart handling and not the types and annotations provided in org.apache.cxf.jaxrs.ext.multipart? Or is there any chance to get support for these types? By default, they are generated by the OpenAPI generator target jax-rs and changing the templates to generate code compatible with the Quarkus-specific implementation is not the easiest task there.

[gsmet]

/cc @michalszynkiewicz

[michalszynkiewicz]

@languitar Quarkus REST Clients are not based on CXF, why would they use CXF classes?
Aoache CXF is an alternative library for JAX-RS (and much more)

[languitar]

Ok, interesting idea. What does this generate for POST routes with multipart uploads?

In our case, we generate Maven packages from the OpenAPI specification for reuse in different microservices. Therefore, the generator needs to be able to create a working project that can be packaged and pushed into a registry. I suspect that doesn't work with the jaxrs-spec generator in a suitable way?

[Postremus]

For multipart uploads, this won't work. Multipart is not part of the jaxrs spec (afaik).
Yes, this won't work for your case, since the generated "client" is not usable without requiring extra code.

The micrprofile templates also only include cxf because of multipart support.
https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/main/resources/Java/libraries/microprofile/api.mustache#L15

Another idea, you could write your own openapi-generator templates, based on the micrprofile ones.
These templates could then use e.g. the multipart support from resteasy. https://quarkus.io/guides/rest-client-multipart

[languitar]

Another idea, you could write your own openapi-generator templates, based on the micrprofile ones.
These templates could then use e.g. the multipart support from resteasy. https://quarkus.io/guides/rest-client-multipart

I've tried that. But that's pretty hard to achieve with only template modifications. By default, form models are not generated and the limited mustache templating makes it close to impossible to generate something working without also implementing a custom code generator java class. So not exactly an easy route to go.

[michalszynkiewicz]

There's some work on a built in code generator for openapi linked to this issue #16401
This extension is where we should make it work easily.

If CXF can put their own custom stuff into the generator maybe we could too, hidden by some switch? I'm not very familiar with the project, unfortunately.

[languitar]

I've tried that and I've also seen that issue. It will probably be possible by providing a custom generator class. Only templating changes are probably not sufficient or at least hard to maintain due to the fact that resteasy multipart requires form data to be a model class. Typical java generators treat form parameter similar to query or path parameters with individual arguments per endpoint method. Getting rid of this behavior is a bit cumbersome.