spring-boot - 使用 BeanPostProcessor 在 Spring 中自定义注解

Question

我们正在尝试在 Spring 中为我们的 rest api 创建一个自定义注释。我是创建自定义注释的新手，我在下面给出了代码片段

Spring Boot 应用程序 --

@SpringBootApplication
@ComponentScan(basePackageClasses = {ServiceController.class, CustomAnnotatorProcessor.class})
public class ServiceApp {
    public static void main(String[] args) {            
        SpringApplication.run(ServiceApp.class, args);
    }
}

休息 Controller --

@RestController
public class ServiceController {

    @RequestMapping(method = RequestMethod.GET, value="/service/v1/version")
    @ApiResponses(value = { 
            @ApiResponse(code = 200, message = "Success", response = String.class),
            @ApiResponse(code = 401, message = "Unauthorized"),
            @ApiResponse(code = 403, message = "Forbidden"),
            @ApiResponse(code = 404, message = "Not Found"),
            @ApiResponse(code = 500, message = "Failure")}) 
    @CustomAnnotation()
    public String getVersion() {
        return "success";
    }
}

自定义注释 --

@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.METHOD})
@Documented
public @interface CustomAnnotation {

}

注解处理器--

@Component
public class CustomAnnotatorProcessor implements BeanPostProcessor {    

private ConfigurableListableBeanFactory configurableBeanFactory;

@Autowired
public CustomAnnotatorProcessor(ConfigurableListableBeanFactory beanFactory) {
    this.configurableBeanFactory = beanFactory;
}

@Override
public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
    return bean;
}

@Override
public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
    MethodCallback methodCallback = new CustomAnnotationMethodCallback(configurableBeanFactory, bean);
    ReflectionUtils.doWithMethods(bean.getClass(), methodCallback);
    return bean;
}

方法回调--

public class CustomAnnotationMethodCallback implements MethodCallback{
    @Override
    public void doWith(Method method) throws IllegalArgumentException, IllegalAccessException {
        if (method.isAnnotationPresent(CustomAnnotation.class)) {
            System.out.println("doWith is getting called for CustomAnnotationMethodCallback");
            ReflectionUtils.makeAccessible(method);     
            //DO VALIDATION WHETHER A SPECIFIC HEADER IS PRESENT IN THE GIVEN REQUEST
            return;
        }       
    }

}   

我正在尝试在实现 BeanPostProcessor 的类中处理自定义注释，但我遇到了问题

问题_1:回调被调用一次，但我无法对进入/service/v1/version API 的每个请求应用验证。我需要验证每个请求，我们的设计/方法是否正确，如果正确如何解决这个问题，如果不正确，请提出不同的方法

问题_2:如果我需要将完整的请求对象(与 header 一起)传递到我的@customAnnotation，我应该怎么做？

如果您需要更多详细信息，请告诉我

谢谢

Answer 1

为了处理自定义注释@validateAuthentication，我们创建了扩展HandlerInterceptorAdapter 的拦截器类。

我们在 preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) 方法中实现请求 header 的验证。