spring-boot - 拦截请求并发送到外部

Question

我正在开发一个 Spring Boot 项目。

我的 Controller 的一个例子:

@Controller
public class RestController {

    @GetMapping(value = "/student/{studentId}")
    public @ResponseBody Student getData(@PathVariable Integer studentId) {
        Student student = new Student();
        student.setName("Peter");
        student.setId(studentId);

        return student;
    }
}

我也实现了其他端点。

我需要拦截每个到达我的端点的请求并将请求转发到另一个服务(微服务)，换句话说，我需要将每个请求转发到另一个 Web 应用程序，该 Web 应用程序与当前运行在同一台本地机器上，基于来自那个的响应服务来决定是否继续转发请求。

我的粗略想法是使用 HandlerIntercept ，但我不确定我是否朝着正确的方向前进。有人可以分享一些经验，实现这一目标的最佳方法是什么？如果您能展示一些示例代码，那就太好了。提前致谢。

Answer 1

您可以使用 HandlerInterceptorAdapter。

如下定义拦截器。

@Component
public class RequestInterceptor extends HandlerInterceptorAdapter {

    @Override
    public boolean preHandle(HttpServletRequest request,
                             HttpServletResponse response, Object object) throws Exception {
        System.out.println("In preHandle we are Intercepting the Request");
        System.out.println("____________________________________________");
        //Call the Rest API and Validate 
        if (conditionsNotMet()) {
           response.getWriter().write("something");
           response.setStatus(someErrorCode);

           return false;
        }
    }

}

注册 HandlerInterceptorAdapter

@Configuration
public class PathMatchingConfigurationAdapter extends WebMvcConfigurerAdapter {

    @Autowired
    private RequestInterceptor requestInterceptor;

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(requestInterceptor);
    }
}

使用 WebMvcConfigurer

@Configuration
public class PathMatchingConfigurationAdapter implements WebMvcConfigurer {

    @Autowired
    private RequestInterceptor requestInterceptor;

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(requestInterceptor);
    }

    @Override
    public void addResourceHandlers(ResourceHandlerRegistry resourceHandlerRegistry) {

    }

    @Override
    public void addCorsMappings(CorsRegistry corsRegistry) {

    }

    @Override
    public void addViewControllers(ViewControllerRegistry viewControllerRegistry) {

    }

    @Override
    public void configureViewResolvers(ViewResolverRegistry viewResolverRegistry) {

    }

    @Override
    public void addArgumentResolvers(List<HandlerMethodArgumentResolver> list) {

    }

    @Override
    public void addReturnValueHandlers(List<HandlerMethodReturnValueHandler> list) {

    }

    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> list) {

    }

    @Override
    public void extendMessageConverters(List<HttpMessageConverter<?>> list) {

    }

    @Override
    public void configureHandlerExceptionResolvers(List<HandlerExceptionResolver> list) {

    }

    @Override
    public void extendHandlerExceptionResolvers(List<HandlerExceptionResolver> list) {

    }

    @Override
    public Validator getValidator() {
        return null;
    }

    @Override
    public MessageCodesResolver getMessageCodesResolver() {
        return null;
    }

    @Override
    public void configureContentNegotiation(ContentNegotiationConfigurer configurer) {
        configurer.favorPathExtension(false);
    }

    @Override
    public void configureAsyncSupport(AsyncSupportConfigurer asyncSupportConfigurer) {

    }

    @Override
    public void configureDefaultServletHandling(DefaultServletHandlerConfigurer defaultServletHandlerConfigurer) {

    }

    @Override
    public void addFormatters(FormatterRegistry formatterRegistry) {

    }

    @Override
    public void configurePathMatch(PathMatchConfigurer configurer) {
        configurer.setUseSuffixPatternMatch(false);
    }
}