November 2023

  • openapi-processor-spring/micronaut 2023.6

support different enum styles

it is now possible to (globally) configure different enum types in mapping.yaml:

openapi-processor-mapping: v5

  package-name: generated
  enum-type: default|string|framework

default, which is default, creates a simple java enum with all uppercase enum values. It will create the same code as previous versions.

string, simply uses String and does not create an enum class. This is useful if automatic conversion of the incoming value to a java enum value does not work. In case bean-validation is enabled the processor adds a (generated) validation annotation that verifies that the string is a valid (OpenAPI) enum value.

public interface FooApi {
    @Mapping(path = "/foo", produces = {"application/json"})
    Foo postFoo(@Parameter(name = "enum") @Values(values = {"one", "two"}) String aEnum);

framework, is a placeholder for framework specific enum generation, only supported by openapi-processor-spring.

It generates a Java enum class similar to the default enum type. In addition, it generates a Spring ConverterFactory that Spring can use to convert incoming enum values to its corresponding java enum value (if passed as a parameter, not as part of the body).

To enable the ConverterFactory, create a configuration class like this:

package io.openapiprocessor.samples;

import {package-name}.spring.StringToEnumConverterFactory;
import org.springframework.context.annotation.Configuration;
import org.springframework.format.FormatterRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

public class WebConfig implements WebMvcConfigurer {

    public void addFormatters(FormatterRegistry registry) {
        registry.addConverterFactory(new StringToEnumConverterFactory());

This registration is one time task. The converter factory does create an enum converter for all generated enum classes.

There is a sample that is using different enum-type configurations (string & framework).