如何避免swagger codegen接口中的默认方法实现？

Question

I would like to avoid "default" implementation in interface generate by the maven plugin swagger codegen. For example, with petstore swagger : http://petstore.swagger.io/v2/swagger.json

I generate interface with maven plugin :

            <plugin>
            <groupId>io.swagger</groupId>
            <artifactId>swagger-codegen-maven-plugin</artifactId>
            <version>2.2.3</version>
            <executions>
                <execution>
                    <goals>
                        <goal>generate</goal>
                    </goals>
                    <configuration>
                        <inputSpec>./src/main/resources/swagger/api.yml</inputSpec>
                        <language>spring</language>
                        <generateSupportingFiles>false</generateSupportingFiles>
                        <configOptions>
                            <interfaceOnly>true</interfaceOnly>
                            <java8>true</java8>
                        </configOptions>
                    </configuration>
                </execution>
            </executions>
        </plugin>

I generate interface like PetApi.java with default implementation of methods :

    default ResponseEntity<Void> addPet(@ApiParam(value = "Pet object that needs to be added to the store" ,required=true )  @Valid @RequestBody Pet body) {
    // do some magic!
    return new ResponseEntity<Void>(HttpStatus.OK);
    }

I would like to avoid it like

    ResponseEntity<Void> addPet(@ApiParam(value = "Pet object that needs to be added to the store" ,required=true )  @Valid @RequestBody Pet body);

Is it possible to do it ?

Update March 2020:

According to new OpenAPI Tool openapi-generator
There is an option with spring ( language is DEPRECATED, use generatorName )

skipDefaultInterface

https://github.com/OpenAPITools/openapi-generator/blob/master/docs/generators/spring.md

Answer 1

With a "spring" language the "java8" parameter is used both to signal use of the default interface and to signal general use of Java8, eg when the Java8 date library is used.
Related tickets:
https://github.com/swagger-api/swagger-codegen/issues/8045
https://github.com/swagger-api/swagger-codegen/issues/5614

Answer 2

I resolved configuring two executions of same plugin. One with configuration to generate only the model classes (java8=true and dateLibrary=java8-localdatetime) and another to generate only the api interfaces (java=false and dateLibrary empty).

<plugin>
   <groupId>io.swagger.codegen.v3</groupId>
   <artifactId>swagger-codegen-maven-plugin</artifactId>
   <version>3.0.8</version>
   <executions>
      <execution>
         <id>gera-api-model</id>
         <goals>
            <goal>generate</goal>
         </goals>
         <configuration>
            <inputSpec>${project.basedir}/src/main/openapi-spec/openapi.yaml</inputSpec>
            <language>spring</language>

            <generateModels>true</generateModels>
            <generateApis>false</generateApis>
            <configOptions>
               <dateLibrary>java8-localdatetime</dateLibrary>
               <java8>true</java8> 
             </configOptions>
         </configuration>
      </execution>
      <execution>
         <id>gera-api-interface</id>
         <goals>
            <goal>generate</goal>
         </goals>
         <configuration>
            <inputSpec>${project.basedir}/src/main/openapi-spec/openapi.yaml</inputSpec>
            <language>spring</language>
            <generateModels>false</generateModels>
            <generateApis>true</generateApis>
            <configOptions>
               <java8>false</java8>
            </configOptions>
         </configuration>
      </execution>
   </executions>
   <configuration>
      <inputSpec>${project.basedir}/src/main/openapi-spec/openapi.yaml</inputSpec>
      <language>spring</language>
      <output>${project.build.directory}/generated-sources</output>
      <apiPackage>br.com.acme.myproject.api</apiPackage>
      <modelPackage>br.com.acme.myproject.model</modelPackage>
      <library>spring-mvc</library>
      <generateApiDocumentation>false</generateApiDocumentation>
      <generateModelDocumentation>false</generateModelDocumentation>
      <generateSupportingFiles>false</generateSupportingFiles>
      <generateApiTests>false</generateApiTests>
      <generateModelTests>false</generateModelTests>
      <configOptions>
         <bigDecimalAsString>true</bigDecimalAsString>
         <serializableModel>true</serializableModel>
         <reactive>false</reactive>
         <interfaceOnly>true</interfaceOnly>
      </configOptions>
   </configuration>
   <dependencies>
      <dependency>
         <groupId>io.swagger.codegen.v3</groupId>
         <artifactId>swagger-codegen-generators</artifactId>
         <version>1.0.8</version>
      </dependency>
   </dependencies>
</plugin>

Note: I am using the version 'v3' of the plugin.

Answer 3

I managed to avoid these default methods by using < java8 > false < /java8 > in the project forked from swagger codegen: https://github.com/OpenAPITools/openapi-generator

Example that works for me:

<plugin>
    <groupId>org.openapitools</groupId>
    <artifactId>openapi-generator-maven-plugin</artifactId>
    <version>4.0.0</version>
    <executions>
        <execution>
            <goals>
                <goal>generate</goal>
            </goals>
            <configuration>
                <inputSpec>${maven.multiModuleProjectDirectory}/api/target/generated/swagger-api-spec/swagger.json</inputSpec>  
                            <language>spring</language>
                            <library>spring-boot</library>
                <skipValidateSpec>true</skipValidateSpec>
                <generateSupportingFiles>true</generateSupportingFiles>
                <configOptions>
                    <sourceFolder>src/gen/java/main</sourceFolder>
                    <java8>false</java8>
                    <dateLibrary>java8</dateLibrary>
                    <interfaceOnly>false</interfaceOnly>
                    <groupId>com.company.groupid</groupId>
                    <artifactId>${project.artifactId}</artifactId>
                    <artifactVersion>${project.version}</artifactVersion>
                </configOptions>
            </configuration>
        </execution>
    </executions>
</plugin>