docs.openapiprocessor.io

January 2026

  • openapi-processor-spring/micronaut 2026.1

add (marker) interfaces to schema classes via mapping

this version adds interface mapping. This makes it possible to let the generated pojos/records implement (marker) interfaces.

mapping.yaml
openapi-processor-mapping: v16

options:
  package-name: io.openapiprocessor.openapi
  model-type: record

map:
  types:
    - type: Foo =+ java.io.Serializable

    # apply the mapping to ALL generated models/DTOs
    - type: object =+ java.io.Serializable

  parameters:
    - type: Bar =+ java.io.Serializable

  # can be used at endpoint level, makes only sense if the models/DTOs are specific to the endpoint
  paths:
    /foo:
      types:
        - type: Foo =+ java.io.Serializable

      parameters:
        - type: Foo =+ java.io.Serializable

      get:
        types:
          - type: Foo =+ java.io.Serializable

        parameters:
          - type: Foo =+ java.io.Serializable

This would generate a Foo model/DTO like this:

Foo.java
@Generated(value = "openapi-processor-spring",  version = "2026.1")
public record Foo(@JsonProperty("foo") String foo) implements Serializable {}

alternative mapping keywords

the mapping does understand keywords additionally to the mapping operators. Instead of using the operators, it is possible to use map, annotate, or implement.

keywords
some-key: {source type} => {target type}
some-key: {source type} map {target type}

some-key: {source type} @ {target type}
some-key: {source type} annotate {target type}

some-key: {source type} =+ {target type}
some-key: {source type} implement {target type}

oneOf interface

generation of the oneOf interface does no longer duplicate the interface in the implements list.

configure allowed targets for annotations

annotation mapping may place annotations on types, fields, methods or parameters where an annotation is not allowed, i.e., java.lang.annotation.Target does not include that target (type, field, etc.)

openapi-processor can’t check the allowed targets of java.lang.annotation.Target directly, because the annotations are not available on its classpath. They are just strings.

To solve this issue, it is now possible to configure the allowed targets of an annotation. The mapping.yaml has a new section annotation-targets. This is a map from annotation name to set of allowed targets.

mapping.yaml
openapi-processor-mapping: v16
options:
  package-name: pkg

map:
  types:
    - type: Foo @ lombok.Builder

annotation-targets:
  # possible entries 'type', 'field', 'method' & 'parameter'
  lombok.Builder: ['type', 'method']

You don’t have to explicitly add lombok.Builder. openapi-processor has a default list of know annotations. If there are other common annotations, I can add them to the default list.

The default list is quite short at the moment:

current default list

  • lombok.Builder: ['type', 'method']