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springboot 拦挡形式
理论我的项目中,咱们常常须要输入申请参数,响应后果,办法耗时,对立的权限校验等。
本文首先为大家介绍 HTTP 申请中三种常见的拦挡实现,并且比拟一下其中的差别。
(1)基于 Aspect 的拦挡形式
(2)基于 HandlerInterceptor 的拦挡形式
(3)基于 ResponseBodyAdvice 的拦挡形式
举荐浏览:
对立日志框架: https://github.com/houbb/auto-log
springboot 入门案例
为了便于大家学习,咱们首先从最根本的 springboot 例子讲起。
maven 引入
引入必须的 jar 包。
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.9.RELEASE</version>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjrt</artifactId>
<version>1.8.10</version>
</dependency>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.8.10</version>
</dependency>
</dependencies>
<!-- Package as an executable jar -->
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
启动类
实现最简略的启动类。
@SpringBootApplication
public class Application {public static void main(String[] args) {SpringApplication.run(Application.class, args);
}
}
定义 Controller
为了演示不便,咱们首先实现一个简略的 controller。
@RestController
public class IndexController {@RequestMapping("/index")
public AsyncResp index() {AsyncResp asyncResp = new AsyncResp();
asyncResp.setResult("ok");
asyncResp.setRespCode("00");
asyncResp.setRespDesc("胜利");
System.out.println("IndexController#index:" + asyncResp);
return asyncResp;
}
}
其中 AsyncResp 的定义如下:
public class AsyncResp {
private String respCode;
private String respDesc;
private String result;
// getter & setter & toString()}
拦挡形式定义
基于 Aspect
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.annotation.EnableAspectJAutoProxy;
import org.springframework.stereotype.Component;
import java.util.Arrays;
/**
*
* @author binbin.hou
* @since 1.0.0
*/
@Aspect
@Component
@EnableAspectJAutoProxy
public class AspectLogInterceptor {
/**
* 日志实例
* @since 1.0.0
*/
private static final Logger LOG = LoggerFactory.getLogger(AspectLogInterceptor.class);
/**
* 拦挡 controller 下所有的 public 办法
*/
@Pointcut("execution(public * com.github.houbb.springboot.learn.aspect.controller..*(..))")
public void pointCut() {//}
/**
* 拦挡解决
*
* @param point point 信息
* @return result
* @throws Throwable if any
*/
@Around("pointCut()")
public Object around(ProceedingJoinPoint point) throws Throwable {
try {
//1. 设置 MDC
// 获取以后拦挡的办法签名
String signatureShortStr = point.getSignature().toShortString();
//2. 打印入参信息
Object[] args = point.getArgs();
LOG.info("{} 参数: {}", signatureShortStr, Arrays.toString(args));
//3. 打印后果
Object result = point.proceed();
LOG.info("{} 后果: {}", signatureShortStr, result);
return result;
} finally {// 移除 mdc}
}
}
这种实现的长处是比拟通用,能够联合注解实现更加灵便弱小的性能。
是集体十分喜爱的一种形式。
主要用途:
(1)日志的出参 / 入参
(2)对立设置 TraceId
(3)办法的调用耗时统计
基于 HandlerInterceptor
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import javax.servlet.DispatcherType;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* @author binbin.hou
* @since 1.0.0
*/
@Component
public class LogHandlerInterceptor implements HandlerInterceptor {private Logger logger = LoggerFactory.getLogger(LogHandlerInterceptor.class);
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
// 对立的权限校验、路由等
logger.info("LogHandlerInterceptor#preHandle 申请地址:{}", request.getRequestURI());
if (request.getDispatcherType().equals(DispatcherType.ASYNC)) {return true;}
return true;
}
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {logger.info("LogHandlerInterceptor#postHandle 调用");
}
@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {}}
而后须要指定对应的 url 和拦挡形式之间的关系才会失效:
import com.github.houbb.springboot.learn.aspect.aspect.LogHandlerInterceptor;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
/**
* spring mvc 配置
* @since 1.0.0
*/
@Configuration
public class SpringMvcConfig extends WebMvcConfigurerAdapter {
@Autowired
private LogHandlerInterceptor logHandlerInterceptor;
@Override
public void addInterceptors(InterceptorRegistry registry) {registry.addInterceptor(logHandlerInterceptor)
.addPathPatterns("/**")
.excludePathPatterns("/version");
super.addInterceptors(registry);
}
}
这种形式的长处就是能够依据 url 灵便指定不同的拦挡形式。
毛病是次要用于 Controller 层。
基于 ResponseBodyAdvice
此接口有 beforeBodyWrite 办法,参数 body 是响应对象 response 中的响应体,那么咱们就能够用此办法来对响应体做一些对立的操作。
比方加密,签名等。
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.MethodParameter;
import org.springframework.http.MediaType;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.server.ServerHttpRequest;
import org.springframework.http.server.ServerHttpResponse;
import org.springframework.http.server.ServletServerHttpRequest;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.servlet.mvc.method.annotation.ResponseBodyAdvice;
import javax.servlet.http.HttpServletRequest;
/**
* @author binbin.hou
* @since 1.0.0
*/
@ControllerAdvice
public class MyResponseBodyAdvice implements ResponseBodyAdvice<Object> {
/**
* 日志实例
* @since 1.0.0
*/
private static final Logger LOG = LoggerFactory.getLogger(MyResponseBodyAdvice.class);
@Override
public boolean supports(MethodParameter methodParameter, Class aClass) {
// 这个中央如果返回 false, 不会执行 beforeBodyWrite 办法
return true;
}
@Override
public Object beforeBodyWrite(Object resp, MethodParameter methodParameter, MediaType mediaType, Class<? extends HttpMessageConverter<?>> aClass, ServerHttpRequest serverHttpRequest, ServerHttpResponse serverHttpResponse) {String uri = serverHttpRequest.getURI().getPath();
LOG.info("MyResponseBodyAdvice#beforeBodyWrite 申请地址:{}", uri);
ServletServerHttpRequest servletServerHttpRequest = (ServletServerHttpRequest) serverHttpRequest;
HttpServletRequest servletRequest = servletServerHttpRequest.getServletRequest();
// 能够做对立的拦挡形式解决
// 能够对后果做动静批改等
LOG.info("MyResponseBodyAdvice#beforeBodyWrite 响应后果:{}", resp);
return resp;
}
}
测试
咱们启动利用,页面拜访:
http://localhost:18080/index
页面响应:
{"respCode":"00","respDesc":"胜利","result":"ok"}
后端日志:
c.g.h.s.l.a.a.LogHandlerInterceptor : LogHandlerInterceptor#preHandle 申请地址:/index
c.g.h.s.l.a.aspect.AspectLogInterceptor : IndexController.index() 参数: []
IndexController#index:AsyncResp{respCode='00', respDesc='胜利', result='ok'}
c.g.h.s.l.a.aspect.AspectLogInterceptor : IndexController.index() 后果: AsyncResp{respCode='00', respDesc='胜利', result='ok'}
c.g.h.s.l.a.aspect.MyResponseBodyAdvice : MyResponseBodyAdvice#beforeBodyWrite 申请地址:/index
c.g.h.s.l.a.aspect.MyResponseBodyAdvice : MyResponseBodyAdvice#beforeBodyWrite 响应后果:AsyncResp{respCode='00', respDesc='胜利', result='ok'}
c.g.h.s.l.a.a.LogHandlerInterceptor : LogHandlerInterceptor#postHandle 调用
这里执行的先后顺序也比拟明确,此处不再赘述。
异步执行
当然,如果只是下面这些内容,并不是本篇文章的重点。
接下来,咱们一起来看下,如果引入了异步执行会怎么样。
定义异步线程池
springboot 中定义异步线程池,非常简单。
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.task.AsyncTaskExecutor;
import org.springframework.scheduling.annotation.EnableAsync;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
/**
* 申请异步解决配置
*
* @author binbin.hou
*/
@Configuration
@EnableAsync
public class SpringAsyncConfig {@Bean(name = "asyncPoolTaskExecutor")
public AsyncTaskExecutor taskExecutor() {ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setMaxPoolSize(10);
executor.setQueueCapacity(10);
executor.setCorePoolSize(10);
executor.setWaitForTasksToCompleteOnShutdown(true);
return executor;
}
}
异步执行的 Controller
@RestController
public class MyAsyncController extends BaseAsyncController<String> {
@Override
protected String process(HttpServletRequest request) {return "ok";}
@RequestMapping("/async")
public AsyncResp hello(HttpServletRequest request) {AsyncResp resp = super.execute(request);
System.out.println("Controller#async 后果:" + resp);
return resp;
}
}
其中 BaseAsyncController 的实现如下:
@RestController
public abstract class BaseAsyncController<T> {protected abstract T process(HttpServletRequest request);
@Autowired
private AsyncTaskExecutor taskExecutor;
protected AsyncResp execute(HttpServletRequest request) {
// 异步响应后果
AsyncResp resp = new AsyncResp();
try {taskExecutor.execute(new Runnable() {
@Override
public void run() {
try {T result = process(request);
resp.setRespCode("00");
resp.setRespDesc("胜利");
resp.setResult(result.toString());
} catch (Exception exception) {resp.setRespCode("98");
resp.setRespDesc("工作异样");
}
}
});
} catch (TaskRejectedException e) {resp.setRespCode("99");
resp.setRespDesc("工作回绝");
}
return resp;
}
}
execute 的实现也比较简单:
(1)主线程创立一个 AsyncResp,用于返回。
(2)线程池异步执行具体的子类办法,并且设置对应的值。
思考
接下来,问大家一个问题。
如果咱们申请 http://localhost:18080/async,那么:
(1)页面失去的返回值是什么?
(2)Aspect 日志输入的返回值是?
(3)ResponseBodyAdvice 日志输入的返回值是什么?
你能够在这里略微停一下,记录下你的答案。
测试
咱们页面申请 http://localhost:18080/async。
页面响应如下:
{"respCode":"00","respDesc":"胜利","result":"ok"}
后端的日志:
c.g.h.s.l.a.a.LogHandlerInterceptor : LogHandlerInterceptor#preHandle 申请地址:/async
c.g.h.s.l.a.aspect.AspectLogInterceptor : MyAsyncController.hello(..) 参数: [org.apache.catalina.connector.RequestFacade@7e931750]
Controller#async 后果:AsyncResp{respCode='null', respDesc='null', result='null'}
c.g.h.s.l.a.aspect.AspectLogInterceptor : MyAsyncController.hello(..) 后果: AsyncResp{respCode='null', respDesc='null', result='null'}
c.g.h.s.l.a.aspect.MyResponseBodyAdvice : MyResponseBodyAdvice#beforeBodyWrite 申请地址:/async
c.g.h.s.l.a.aspect.MyResponseBodyAdvice : MyResponseBodyAdvice#beforeBodyWrite 响应后果:AsyncResp{respCode='00', respDesc='胜利', result='ok'}
c.g.h.s.l.a.a.LogHandlerInterceptor : LogHandlerInterceptor#postHandle 调用
比照一下,能够发现咱们下面问题的答案:
(1)页面失去的返回值是什么?
{"respCode":"00","respDesc":"胜利","result":"ok"}
能够获取到异步执行实现的后果。
(2)Aspect 日志输入的返回值是?
AsyncResp{respCode='null', respDesc='null', result='null'}
无奈获取异步后果。
(3)ResponseBodyAdvice 日志输入的返回值是什么?
AsyncResp{respCode='00', respDesc='胜利', result='ok'}
能够获取到异步执行实现的后果。
这个看起来有些奇怪,实质上起因是什么呢?又怎么验证呢?
异步执行
起因
实质上,异步执行和 spring 自身的机制关系不大。
只不过是异步执行的办法自身须要工夫,拦挡形式越靠后,如果异步执行完了,刚好就能够获取到对应的信息而已。
验证形式
如何验证这个猜测呢?
咱们在 process 中增加一个 sleep 即可。
代码调整
- BaseAsyncController.java
execute 中增加一些执行的日志信息,便于查看工夫。
taskExecutor.execute(new Runnable() {
@Override
public void run() {
try {logger.info("AsyncResp#execute 异步开始执行。");
T result = process(request);
resp.setRespCode("00");
resp.setRespDesc("胜利");
resp.setResult(result.toString());
logger.info("AsyncResp#execute 异步实现执行。");
} catch (Exception exception) {resp.setRespCode("98");
resp.setRespDesc("工作异样");
}
}
});
- MyAsyncController.java
执行时增加沉睡工夫。
@Override
protected String process(HttpServletRequest request) {
try {TimeUnit.SECONDS.sleep(5);
return "ok";
} catch (InterruptedException e) {return "error";}
}
测试
页面拜访 http://localhost:18080/async
页面返回如下:
{"respCode":null,"respDesc":null,"result":null}
对应的日志如下:
2021-07-10 09:16:08.661 INFO 11008 --- [io-18080-exec-1] c.g.h.s.l.a.a.LogHandlerInterceptor : LogHandlerInterceptor#preHandle 申请地址:/async
2021-07-10 09:16:08.685 INFO 11008 --- [io-18080-exec-1] c.g.h.s.l.a.aspect.AspectLogInterceptor : MyAsyncController.hello(..) 参数: [org.apache.catalina.connector.RequestFacade@1d491e0]
Controller#async 后果:AsyncResp{respCode='null', respDesc='null', result='null'}
2021-07-10 09:16:08.722 INFO 11008 --- [io-18080-exec-1] c.g.h.s.l.a.aspect.AspectLogInterceptor : MyAsyncController.hello(..) 后果: AsyncResp{respCode='null', respDesc='null', result='null'}
2021-07-10 09:16:08.722 INFO 11008 --- [lTaskExecutor-1] c.g.h.s.l.a.c.BaseAsyncController : AsyncResp#execute 异步开始执行。2021-07-10 09:16:08.777 INFO 11008 --- [io-18080-exec-1] c.g.h.s.l.a.aspect.MyResponseBodyAdvice : MyResponseBodyAdvice#beforeBodyWrite 申请地址:/async
2021-07-10 09:16:08.777 INFO 11008 --- [io-18080-exec-1] c.g.h.s.l.a.aspect.MyResponseBodyAdvice : MyResponseBodyAdvice#beforeBodyWrite 响应后果:AsyncResp{respCode='null', respDesc='null', result='null'}
2021-07-10 09:16:08.797 INFO 11008 --- [io-18080-exec-1] c.g.h.s.l.a.a.LogHandlerInterceptor : LogHandlerInterceptor#postHandle 调用
2021-07-10 09:16:13.729 INFO 11008 --- [lTaskExecutor-1] c.g.h.s.l.a.c.BaseAsyncController : AsyncResp#execute 异步实现执行。
能够发现 spring 自身仍然依照失常的流程执行,因为 process 的执行工夫过长,导致三种拦挡形式都是无奈获取异步内容。
反思
写到这里,本人的播种还是不少。
(1)拦截器的叫法问题
平时会习惯的叫日志拦截器之类的,所以一开始题目应用的是 3 种拦截器,诚然,谨严的说并不能将这些一概而论。
否则,就如评论区所言,filter 也能够称为拦截器了。
所以将拦截器对立修改为拦挡形式。
(2)对常识的了解问题
第一次实现的时候,因为 process 工夫太短,让人产生误以为 spring 会有非凡的解决机制。
学习自身还是要谨严一些,所以本文从新做了修改。
小结
心愿本文对你有帮忙,如果有其余想法的话,也能够评论区和大家分享哦。
各位极客的点赞珍藏转发,是老马继续写作的最大能源!
我是老马,期待与你的下次重逢。