스코프와 Provider

 

스코프와 Provider

앞선 포스팅에서 나온 에러를 잡는 방법을 살펴보자

 

LogDemoController 수정

@Controller
@RequiredArgsConstructor
public class LogDemoController {

    private final LogDemoService logDemoService;
    private final ObjectProvider<MyLogger> myLoggerProvider; // 이것도 타입 바꿔줌

    @RequestMapping("log-demo")
    @ResponseBody
    public String logDemo(HttpServletRequest request) {

        String requestURL = request.getRequestURL().toString();
        MyLogger myLogger = myLoggerProvider.getObject(); // 여기서 꺼낸다.
        myLogger.setRequestURL(requestURL);

        myLogger.log("controller test");
        logDemoService.logic("testId");
        return "OK";
    }
}

이렇게 바꿔서 실행해도

똑같은 에러가 나온다.

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'logDemoService' defined in file [C:\Inflearn_Spring\spring_core\out\production\classes\inflearn\spring_core\logdemo\LogDemoService.class]: Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.support.ScopeNotActiveException: Error creating bean with name 'myLogger': Scope 'request' is not active for the current thread; consider defining a scoped proxy for this bean if you intend to refer to it from a singleton; nested exception is java.lang.IllegalStateException: No thread-bound request found: Are you referring to request attributes outside of an actual web request, or processing a request outside of the originally receiving thread? If you are actually operating within a web request and still receive this message, your code is probably running outside of DispatcherServlet: In this case, use RequestContextListener or RequestContextFilter to expose the current request.
	at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:801) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:224) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1372) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1222) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:582) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:955) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:921) ~[spring-context-5.3.30.jar:5.3.30]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:583) ~[spring-context-5.3.30.jar:5.3.30]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:147) ~[spring-boot-2.7.16.jar:2.7.16]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:731) ~[spring-boot-2.7.16.jar:2.7.16]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:408) ~[spring-boot-2.7.16.jar:2.7.16]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:307) ~[spring-boot-2.7.16.jar:2.7.16]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1303) ~[spring-boot-2.7.16.jar:2.7.16]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1292) ~[spring-boot-2.7.16.jar:2.7.16]
	at inflearn.spring_core.SpringCoreApplication.main(SpringCoreApplication.java:10) ~[classes/:na]
Caused by: org.springframework.beans.factory.support.ScopeNotActiveException: Error creating bean with name 'myLogger': Scope 'request' is not active for the current thread; consider defining a scoped proxy for this bean if you intend to refer to it from a singleton; nested exception is java.lang.IllegalStateException: No thread-bound request found: Are you referring to request attributes outside of an actual web request, or processing a request outside of the originally receiving thread? If you are actually operating within a web request and still receive this message, your code is probably running outside of DispatcherServlet: In this case, use RequestContextListener or RequestContextFilter to expose the current request.
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:383) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1391) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1311) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:911) ~[spring-beans-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:788) ~[spring-beans-5.3.30.jar:5.3.30]
	... 19 common frames omitted
Caused by: java.lang.IllegalStateException: No thread-bound request found: Are you referring to request attributes outside of an actual web request, or processing a request outside of the originally receiving thread? If you are actually operating within a web request and still receive this message, your code is probably running outside of DispatcherServlet: In this case, use RequestContextListener or RequestContextFilter to expose the current request.
	at org.springframework.web.context.request.RequestContextHolder.currentRequestAttributes(RequestContextHolder.java:131) ~[spring-web-5.3.30.jar:5.3.30]
	at org.springframework.web.context.request.AbstractRequestAttributesScope.get(AbstractRequestAttributesScope.java:42) ~[spring-web-5.3.30.jar:5.3.30]
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:371) ~[spring-beans-5.3.30.jar:5.3.30]
	... 25 common frames omitted


Process finished with exit code 1

 

서비스 부분을 고친다.

LogDemoService 수정

@Service
@RequiredArgsConstructor
public class LogDemoService {

    private final ObjectProvider<MyLogger> myLoggerProvider; // 여기

    public void logic(String id) {
        MyLogger myLogger = myLoggerProvider.getObject(); // 이거 추가
        myLogger.log("service id = " + id);
    }
}

 

이제 다시 SpringCoreApplication 실행하면

문제 없이 실행이 된다.

화면 잘 떴고, 콘솔 확인

이 초록색을 보면 동일한 UUID -> 한 명에게 온 요청임을 확인할 수 있음.

두 번 더 새로고참을 햅면

이렇게 같은 요청을 구분 가능

 

코드의 동작 흐름을 보면

    @RequestMapping("log-demo")
    @ResponseBody
    public String logDemo(HttpServletRequest request) {

        String requestURL = request.getRequestURL().toString();
        MyLogger myLogger = myLoggerProvider.getObject();
        myLogger.setRequestURL(requestURL);

        myLogger.log("controller test");
        logDemoService.logic("testId");
        return "OK";
    }

여기서 최초로 만들어지고 

 

 

그러면

여기서

    @PostConstruct
    public void init() {
        uuid = UUID.randomUUID().toString(); // UUID 생성
        System.out.println("[" + uuid + "] request scope bean create:" + this);
    }

init() 이 호출되면서 HttpRequest랑 uuid를 연결시킨다.

 

이제

 myLogger.setRequestURL(requestURL); 여기서 url 세팅이 되었고

 myLogger.log("controller test") 여기서 로그 찍으면 uuid랑 url이랑 다 알기 때문에 깔끔하게 나온다.

 

---

정리

• ObjectProvider 덕분에 ObjectProvider.getObject() 를 호출하는 시점까지 request scope 빈의 생성을 지연할 수 있다.
• ObjectProvider.getObject() 를 호출하시는 시점에는 HTTP 요청이 진행중이므로 request scope 빈의 생성이 정상 처리된다.
• ObjectProvider.getObject() 를 LogDemoController , LogDemoService 에서 각각 한번씩 따로 호출해도 같은 HTTP 요청이면 같은 스프링 빈이 반환된다!

 

정확하게는 빈의 생성의 지연이 아니라 스프링 컨테이너에게 요청을 하는 것을 지연한다.