Nullable enum in query string does not generate compilable code

[brice-laurencin]

If the parameter is defined as @QueryParam("status") status: StatusEnum
the OAS is as such:

- name: status
  in: query
  required: true
  schema:
    $ref: "#/components/schemas/StatusEnum"

And the generated param is @io.quarkiverse.openapi.generator.annotations.GeneratedParam("source") @jakarta.ws.rs.QueryParam("source") EnumType source

If the parameter is defined as @QueryParam("status") status: StatusEnum?

the OAS is as such:

- name: status
  in: query
  required: true
  schema:
    allOf:
      - $ref: "#/components/schemas/StatusEnum"
      - nullable: true

And the generated param is:
@io.quarkiverse.openapi.generator.annotations.GeneratedParam("source") @jakarta.ws.rs.BeanParam EnumType.EnumTypeQueryParam source

Here, it does not compile because EnumType.EnumTypeQueryParam is not generated.

Here is a complete yaml exposing the issue:

openapi: 3.0.3
info:
  title: echo
  version: '1.0.0'
  description: ""
paths:
  /ko:
    post:
      summary: Echo
      operationId: postKo
      parameters:
        - name: source
          in: query
          description: enum value
          required: false
          schema:
            allOf:
              - $ref: "#/components/schemas/EnumType"
              - nullable: true

      responses:
        "200":
          description: OK
  /ok:
    post:
      summary: Echo
      operationId: postOk
      parameters:
        - name: source
          in: query
          description: enum value
          required: false
          schema:
            $ref: "#/components/schemas/EnumType"


      responses:
        "200":
          description: OK

components:
  schemas:
    EnumType:
      enum:
        - SOMETHING
        - ELSE
      type: string

I tried to wrap my head around this, maybe generate a QueryParam class for the enum, but I failed to make sense of it. The enum is just the enum, the QueryParam class is here to explode members of actual classes.

The example yaml is generated from a quarkus project, and I feel the issue could be there and the schema is incorrect.
So I'm unsure this report is valid.

[ricardozanini]

What's the impact of:

@io.quarkiverse.openapi.generator.annotations.GeneratedParam("source") @jakarta.ws.rs.QueryParam("source") EnumType source

Being null?

[brice-laurencin]

not sure I understand the question, but:
in the generated code: it tries to parse the parameter value with EnumType.EnumTypeQueryParam
in the service code, this is business logic I suppose. The controller would handle the query any way it sees fit.

[ricardozanini]

I must run this locally actually to see what's happening. Based on your description, I'm unsure if I'm following what's happening. Maybe my old brain is getting rusty. 😅

[brice-laurencin]

sorry.
I get that the OAS alone can be hard to read. I for one cannot read the matrix 😅

Here is some code with:

• a quarkus service in the root
• a client generated in clients/jvm
• you can have the client built with ./gradlew :clients:jvm:build
• you can then find the client generated code in clients/jvm/build/classes/java/quarkus-generated-sources/open-api-json/care/resilience/patientservice/client/api/GreetingResourceApi.java

We end up with 2 methods for the client (simplified here):

    public io.smallrye.mutiny.Uni<String> helloGet(@jakarta.ws.rs.BeanParam Fred.FredQueryParam fred
    );

    public io.smallrye.mutiny.Uni<String> hiGet(@jakarta.ws.rs.QueryParam("fred") Fred fred
    );

hiGet is mapping to the service method with the non-nullable enum query param
helloGet maps to the nullable one.

helloGet wants a Fred.FredQueryParam attribute, as a BeanParam, where hiGet wants a Fred QueryParam, which is what I'd actually expect, even for a nullable enum. Or so I think, please tell me if I'm wrong.

This class is not generated in the Fred enum:

import com.fasterxml.jackson.annotation.JsonIgnoreProperties;


/**
 * Gets or Sets Fred
 */
@com.fasterxml.jackson.annotation.JsonIgnoreProperties(ignoreUnknown = true)
public enum Fred {
/**
 * Special value if the API response contains some new value not declared in this enum.
 * You should react accordingly.
 */
UNEXPECTED(String.valueOf("unexpected")),
    BOB(String.valueOf("BOB"));

    // caching enum access
    private static final java.util.EnumSet<Fred> values = java.util.EnumSet.allOf(Fred.class);

    private String value;

    Fred(String value){
        this.value = value;
    }

    @com.fasterxml.jackson.annotation.JsonValue
    public String value() {
        return value;
    }

    @Override
    public String toString() {
        return String.valueOf(value);
    }

    @com.fasterxml.jackson.annotation.JsonCreator
    public static Fred fromString(String text) {
        for (Fred b : values) {
            if (String.valueOf(b.value).equalsIgnoreCase(text)) {
                return b;
            }
        }
        return UNEXPECTED;
    }
}

If Fred was a Pojo instead of an enum, I'd have a XQueryParam class generated alongside the Pojo.

Thanks for your help!

[ricardozanini]

Yes, I think it's a bug. To me, Fred enum should be a valid entry, even if nullable. I can't see why not. @hbelmiro @mcruzdev any thoughts?