Spring boot应用程序不等待SIGTERM

Question

我正在尝试为我的spring boot应用程序添加一个SIGTERM支持。为了测试它，我添加了一个控制器映射，它应该模拟长请求：

@RequestMapping(value = "/sleep/{time}", method = RequestMethod.POST)
public void sleep(@PathVariable("time") int time) throws InterruptedException {
    int sleepLimit = 30000;
    if (time >= sleepLimit)
        throw new IllegalArgumentException("Sleep time cannot be more than " + sleepLimit + " ms.");
    Thread.sleep(time);
}

我使用的是嵌入式tomcat。问题在于，在请求处于活动状态时(在docker内的shell脚本中使用CTRL+C、/shutdown端点或陷阱)向进程发送kill SIGTERM时，应用程序会“关闭”测试请求，而不是等待调用完成。下面是调用SIGTERM时的日志：

2015-12-26 20:22:43.812  INFO 11608 --- [       Thread-8] ationConfigEmbeddedWebApplicationContext : Closing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@548753b8: startup date [Sat Dec 26 20:22:13
 IST 2015]; root of context hierarchy
2015-12-26 20:22:43.815  INFO 11608 --- [       Thread-8] o.s.c.support.DefaultLifecycleProcessor  : Stopping beans in phase 0
2015-12-26 20:22:43.854  INFO 11608 --- [       Thread-8] o.s.j.e.a.AnnotationMBeanExporter        : Unregistering JMX-exposed beans on shutdown
2015-12-26 20:22:43.856  INFO 11608 --- [       Thread-8] o.s.j.d.e.EmbeddedDatabaseFactory        : Shutting down embedded database: url='jdbc:hsqldb:mem:testdb'
2015-12-26 20:22:43.880  INFO 11608 --- [       Thread-8] org.mongodb.driver.connection            : Closed connection [connectionId{localValue:2, serverValue:2}] to 127.0.0.1:26140 because the pool has been closed.
2015-12-26 20:22:45.093  WARN 11608 --- [       Thread-3] d.f.e.p.store.CachingArtifactStore       : Already removed de.flapdoodle.embed.process.extract.ImmutableExtractedFileSet@45524cfd for Version{3.0.2}:Windows:B64, emergency shutdown?

如何让我的应用程序等待此请求结束？谢谢!

Answer 1

以下是我对此的解决方案：

import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.actuate.metrics.CounterService;
import org.springframework.boot.actuate.metrics.buffer.BufferMetricReader;
import org.springframework.boot.context.embedded.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Service;

import javax.annotation.PreDestroy;
import javax.servlet.*;
import java.io.IOException;

@Service
@Scope("singleton")
public class ActiveSessionsService {

    private static final org.slf4j.Logger logger = LoggerFactory.getLogger(ActiveSessionsService.class);
    @Autowired
    CounterService counterService;
    @Autowired
    BufferMetricReader metrics;

    @Bean
    public FilterRegistrationBean filterRegistrationBean() {
        Filter filter = new Filter() {
            @Override
            public void init(FilterConfig filterConfig) throws ServletException {
            }

            @Override
            public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
                try {
                    counterService.increment("active-http-sessions");
                    filterChain.doFilter(servletRequest, servletResponse);
                } finally {
                    counterService.decrement("active-http-sessions");
                }
            }

            @Override
            public void destroy() {
            }
        };
        FilterRegistrationBean registrationBean = new FilterRegistrationBean();
        registrationBean.setFilter(filter);
        registrationBean.addUrlPatterns("/base/*");
        return registrationBean;
    }
    @PreDestroy
    public void cleanUp() throws Exception {
        int waitTime=0;
        while (waitTime < 10) {
            if(!isThereActiveRequests())
                break;
            Thread.sleep(1000);
        }
    }

    private boolean isThereActiveRequests() {
        int activeCalls =metrics.findOne("counter.active-http-sessions").getValue().intValue();
        logger.info(activeCalls +" Active sessions");
        return activeCalls>0;
    }
}