Private fields documented with @Schema are not show in swagger file (using lombok)

[tjkeast]

Steps to Reproduce

1. Start a basic Micronaut project with the openapi feature.
2. Create a class with a private field and annotate it with @Schema

Expected Behaviour

The generated swagger file should show the annotated fields even if they are private.

Actual Behaviour

Private fields are not shown.

We use the @Data annotation from lombok to automatically generate getters and setters. The private field is defined in code and documented with @Schema but we cannot annotate the public getters/setters directly since they are generated automatically.

Environment Information

• Windows 10
• Micronaut 2.2.0
• JDK 11

Example Application

https://github.com/TJKeast/micronaut-lombok-issue/tree/master/src

Swagger file output

openapi: 3.0.1
info:
  title: demo
  version: "0.0"
paths:
  /:
    get:
      tags:
      - Test
      summary: Retrieves a test
      operationId: getAll
      parameters: []
      responses:
        "200":
          description: getAll 200 response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TestModel'
components:
  schemas:
    TestModel:
      type: object
      description: A test class

[a-mroz]

I've encountered a similar issue. I figured out that private fields can be annotated and it works if you have a public getter created manually. It doesn't work with Lombok-generated getter or when the getter is package-private. An example app: https://github.com/a-mroz/microservices-example/blob/openapiSchemaIssueExample/recommendations/src/main/java/dev/amroz/microservices/bookshop/recommendations/api/RecommendationResponse.java

[graemerocher]

My guess is Lombok is not retaining the javadoc in the AST

[a-mroz]

I'm not sure how javadoc is used here, but it's highly possible.

What's surprising me more is that it doesn't work with package-private getters either.

[graemerocher]

probably doesn't make any difference since Micronaut processes the source code

[3rdstage]

Add Schema into lombok.copyableAnnotations properties of Lombok configuration and specify @Schema annotation on private field. Then @Schema annotation will be copied to the generated getter and setter.

Create lombok.config file in the root directory of your project (Gradle project, Eclipse project or ...)

lombok.copyableAnnotations += io.swagger.v3.oas.annotations.media.Schema

Then specify @Schema annotation to the private fields of the class

  @Getter
  @NoArgsConstructor(access = AccessLevel.PROTECTED)
  public class AssetDTO {

    @Schema(description = "asset ID")
    private Integer id;

    private AssetState state;

    @Schema(description = "token ID at the NFT contract", minimum="0")
    private Integer tokenId;

    @Schema(description = "asset title")
    private String title;

    @Schema(description = "the author of the asset")
    private String author;

  ...
}

For more, refer followings

• lombok.copyableAnnotations
• Lombok configuration system
• location of lombok.config file in java project