Swagger oneOf类型：Jackson试图实例化接口而不是实现？

Question

我正在使用oneOf功能来定义几种可能进入服务的请求主体属性的模式。在生成的Java客户端代码中，这些模式的Java实现实现了一个接口，但是当我发送请求时，Jackson试图创建该接口的实例，而不是具体的类。

Swagger-codegen版本

<groupId>io.swagger.codegen.v3</groupId>
<artifactId>swagger-codegen-maven-plugin</artifactId>
<version>3.0.14</version>

Swagger声明文件的内容

schemas:
    TestRequest:
      description: 
        Test request
      type:
        object
      required:
        - criteria
      properties:
        criteria:
          oneOf:
           - $ref: '#/components/schemas/CriteriaA'
           - $ref: '#/components/schemas/CriteriaB'
    ...
    CriteriaA:
      description: Criteria A
      type: object
      required:
        - type
        - query
      properties:
        type: 
          description: A description
          type: string
          enum:
           - CriteriaA
      query:
        description: A query.
        type: object

复制步骤

swagger代码生成的Java客户端代码如下：

接口：

public interface OneOfTestRequestCriteria {}

具体类别：

@Schema(description = "")
@javax.annotation.Generated(value = "io.swagger.codegen.v3.generators.java.JavaClientCodegen", date = "2020-01-28T13:06:29.942Z[Europe/London]")
public class CriteriaA implements OneOfTestRequestCriteria {

  @JsonAdapter(TypeEnum.Adapter.class)
  public enum TypeEnum {
    CriteriaA("CriteriaA");

    private String value;

    TypeEnum(String value) {
      this.value = value;
    }
    public String getValue() {
      return value;
    }

    @Override
    public String toString() {
      return String.valueOf(value);
    }
    public static TypeEnum fromValue(String text) {
      for (TypeEnum b : TypeEnum.values()) {
        if (String.valueOf(b.value).equals(text)) {
          return b;
        }
      }
      return null;
    }
    public static class Adapter extends TypeAdapter<TypeEnum> {
      @Override
      public void write(final JsonWriter jsonWriter, final TypeEnum enumeration) throws IOException {
        jsonWriter.value(enumeration.getValue());
      }

      @Override
      public TypeEnum read(final JsonReader jsonReader) throws IOException {
        String value = jsonReader.nextString();
        return TypeEnum.fromValue(String.valueOf(value));
      }
    }
  }  @SerializedName("type")
  private TypeEnum type = null;

  @SerializedName("query")
  private Object query = null;

  public CriteriaA type(TypeEnum type) {
    this.type = type;
    return this;
  }

  @Schema(required = true, description = "")
  public TypeEnum getType() {
    return type;
  }

  public void setType(TypeEnum type) {
    this.type = type;
  }

  public CriteriaA query(Object query) {
    this.query = query;
    return this;
  }

  @Schema(required = true, description = "")
  public Object getQuery() {
    return query;
  }

  public void setQuery(Object query) {
    this.query = query;
  }


  @Override
  public boolean equals(java.lang.Object o) {
    if (this == o) {
      return true;
    }
    if (o == null || getClass() != o.getClass()) {
      return false;
    }
    CriteriaA criteriaA = (CriteriaA ) o;
    return Objects.equals(this.type, criteriaA.type) &&
        Objects.equals(this.query, criteriaA.query);
  }

  @Override
  public int hashCode() {
    return Objects.hash(type, query);
  }


  @Override
  public String toString() {
    StringBuilder sb = new StringBuilder();
    sb.append("class CriteriaA {\n");

    sb.append("    type: ").append(toIndentedString(type)).append("\n");
    sb.append("    query: ").append(toIndentedString(query)).append("\n");
    sb.append("}");
    return sb.toString();
  }

  private String toIndentedString(java.lang.Object o) {
    if (o == null) {
      return "null";
    }
    return o.toString().replace("\n", "\n    ");
  }

}

我正在尝试使用此生成的客户端代码发送请求：

final TestRequest testRequest = new TestRequest();

final CriteriaA criteriaA = new CriteriaA ();
criteriaA .setType(CriteriaA .TypeEnum.CriteriaA);
criteriaA .setQuery("a query");

testRequest .setCriteria(criteriaA );

final ApiResponse<Void> apiResponse = testApi.createOrUpdateTestWithHttpInfo(testRequest);

运行上述客户端代码会在Jackson尝试反序列化时导致此错误。似乎正在尝试构造接口OneOfTestRequestCriteria的实例，而不是接口的具体实现。条件A：

[请求处理失败；嵌套异常为org.springframework.http.converter.HttpMessageConversionException：类型定义错误：[简单类型，类com.acme.tag.models.OneOfTestRequestCriteria]；嵌套异常为com.fasterxml.jackson.databind.exc.InvalidDefinitionException：无法构造com.acme.tag.models.OneOfTestRequestCriteria的实例（否像默认构造一样，创建者也存在）：抽象类型要么需要映射到具体类型，具有自定义反序列化器或包含其他类型信息\ n

如果我注释生成的接口：

public interface OneOfTestRequestCriteria {}

带有以下内容：

@JsonTypeInfo(
  use = JsonTypeInfo.Id.NAME, 
  include = JsonTypeInfo.As.PROPERTY, 
  property = "type")
@JsonSubTypes({ 
  @Type(value = CriteriaA.class, name = "CriteriaA")
})
public interface OneOfTestRequestCriteria {

}

然后将请求正确反序列化为CriteriaA-我是否在swagger.yaml中缺少某些内容，可能导致此接口未被代码生成工具注释？

Answer 1

<groupId>io.swagger.codegen.v3</groupId>
 <artifactId>swagger-codegen-maven-plugin</artifactId>
 <version>3.0.18</version>

https://github.com/swagger-api/swagger-codegen-generators/pull/585