Configuring Swagger

The dependencies are added, now we can configure the infrastructure for Swagger. The configuration is pretty simple. We will create a class with @Configuration to produce the Swagger configuration for the Spring container. Let's do it.

Take a look at the following Swagger configuration:

package springfive.cms.infra.swagger;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.bind.annotation.RestController;
import springfox.documentation.builders.ParameterBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spring.web.plugins.Docket;
import springfox.documentation.swagger2.annotations.EnableSwagger2;

@Configuration
@EnableSwagger2
public class SwaggerConfiguration {

  @Bean
  public Docket documentation() {
    return new Docket(DocumentationType.SWAGGER_2)
        .select()
        .apis(RequestHandlerSelectors.withClassAnnotation(RestController.class))
        .paths(PathSelectors.any())
        .build(); 
  }

}

The @Configuration instructs the Spring to generate a bean definition for Swagger. The annotation, @EnableSwagger2 adds support for Swagger. @EnableSwagger2 should be accompanied by @Configuration, it is mandatory.

The Docket class is a builder to create an API definition, and it provides sensible defaults and convenience methods for configuration of the Spring Swagger MVC Framework.

The invocation of method .apis(RequestHandlerSelectors.withClassAnnotation(RestController.class)) instructs the framework to handle classes annotated with @RestController.

There are many methods to customize the API documentation, for example, there is a method to add authentication headers.

That is the Swagger configuration, in the next section, we will create a first documented API.