getMultiPartFormParameters() always returns EmptyMultivaluedMap after upgrade to Resteasy Reactive

[xgp]

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Area

core

Describe the bug

In RealmResourceProvider extensions that use session.getContext().getHttpRequest().getMultiPartFormParameters() to retrieve parts of a multipart/form-data request, the method now always returns an EmptyMultivaluedMap instead of the parts of the request.

Version

23.0.0

Expected behavior

This should return a MultivaluedMap with the parts represented in the request when given a valid multipart/form-data request. This worked properly in <23.

Actual behavior

It always returns an EmptyMultivaluedMap.

How to Reproduce?

Create a RealmResourceProvider extension that returns the following Object for the getResource() method:

public class TestResource {
  @PUT
  @Consumes(MediaType.MULTIPART_FORM_DATA)
  public Response test() {
    HttpRequest req = session.getContext().getHttpRequest();
    log.infof("mediaType %s", req.getHttpHeaders().getMediaType());
    log.infof("contentType %s", req.getHttpHeaders().getHeaderString("content-type"));

    MediaType mediaType = req.getHttpHeaders().getMediaType();
    log.infof("isCompatible %b", MULTIPART_FORM_DATA_TYPE.isCompatible(mediaType));
    log.infof("hasBoundary %b", mediaType.getParameters().containsKey("boundary"));

    MultivaluedMap<String, FormPartValue> formDataMap = session.getContext().getHttpRequest().getMultiPartFormParameters();
    if (formDataMap != null) {
      log.infof("formDataMap %s", formDataMap);
      for (String k : formDataMap.keySet()) {
        log.infof("key %s", k);
      }
    }
    return Response.noContent().build();
  }
}

Make any multipart/form-data request to it (doesn't matter what's in it, as long as it's valid). The resource method outputs:

[INFO] mediaType multipart/form-data;boundary=hkfxPWUJazkCuZXCBiD7pU6vV0WRLpsBsHhVrqJ
[INFO] contentType multipart/form-data; boundary=hkfxPWUJazkCuZXCBiD7pU6vV0WRLpsBsHhVrqJ
[INFO] isCompatible true
[INFO] hasBoundary true
[INFO] formDataMap org.keycloak.quarkus.runtime.integration.jaxrs.EmptyMultivaluedMap@dfc8632

---

Anything else?

There is a more complete example you can run in an existing extension and see the result in the unit test.

Pull the xgp/23 branch https://github.com/p2-inc/keycloak-themes/tree/xgp/23

Run:
mvn clean install -Dtest=EmailsResourceTest#testGetUpdateTemplateMaster

[rmartinc]

I think the problem is that the method is a PUT. Doing some tests a POST is working for me. And I think the reason for this behavior is in the KeycloakHandlerChainCustomizer. If it's a POST it's forcing the addition of the FormBodyHandler but not in a PUT or any other method.

@xgp I suppose you can force the parsing adding any @FormParam to the method (it can be any name, no matter it's not passed).

@pedroigor FYI. Maybe we need to also add the parser for other methods if the consumes expects the correct media type?

[xgp]

@rmartinc Thanks for pointing to where it actually happens, and the workaround. I can confirm that the workaround works.
@pedroigor I think the FormBodyHandler should be added in the case of POST, PUT and PATCH. Let me know if you agree, and I'll PR the change.

[pedroigor]

@rmartinc You are correct. We should handle the body and support multi-part data when handling those missing HTTP methods.

[pedroigor]

FTR, we only had POST because this is the only HTTP method we are using when processing multi-part requests.

[pedroigor]

@xgp Thanks. Please, send the PR if you have time to work on it. Otherwise, let me know.

[rmartinc]

@xgp if you are interested you can send a PR, but maybe also check !resourceMethod.isFormParamRequired() in the if condition. We don't need to add the form parser if it is already required.

[xgp]

PR #25093

[pedroigor]

@xgp Thanks, again!