[bnasslahsen]

Pull Request

Description

Found while porting springdoc-openapi to Swagger Core 3.0 (feedback in #4991).

With OpenAPI 3.1, a @JsonUnwrapped member also annotated with @Schema(requiredMode = REQUIRED) leaves an empty
property in the model, listed in required too, next to the unwrapped properties. With records, Jackson 3
additionally exposes the component as a synthetic @JsonUnwrapped/<n> creator property, which gets the same
treatment:

public record Example(
        @JsonUnwrapped @Schema(requiredMode = REQUIRED) Inner inner,
        @Schema(requiredMode = REQUIRED) Integer number) {
    public record Inner(@Schema(requiredMode = REQUIRED) String value) {}
}

# before (OpenAPI 3.1)
properties: {value: {type: string}, inner: {}, number: {...}, '@JsonUnwrapped/0': {}}
required: ['@JsonUnwrapped/0', inner, number, value]
# after
properties: {value: {type: string}, number: {...}}
required: [number, value]

Cause: the jsonUnwrappedHandler merges the inner properties and returns null. Then, with OpenAPI 3.1,
getSchemaFromAnnotation rebuilds a schema from the remaining @Schema annotation, and that schema is added as a
property. The fix stops processing the member once the handler has unwrapped it: 7 lines in ModelResolver.

The OpenAPI 3.0 output is unchanged; it was already correct.

Fixes:

Type of Change

• 🐛 Bug fix
• ✨ New feature
• ♻️ Refactor (non-breaking change)
• 🧪 Tests
• 📝 Documentation
• 🧹 Chore (build or tooling)

Checklist

• I have added/updated tests as needed: JacksonJsonUnwrappedTest, covering a record and a class with OpenAPI 3.1
• I have added/updated documentation where applicable: not needed
• The PR title is descriptive
• The code builds and passes tests locally: swagger-core and swagger-rest, on Jackson 3.2.3
• I have linked related issues (if any): [Feature] Support Jackson 3.x release line #4991