@InitBinder autoGrowCollectionLimit

백엔드/spring

@InitBinder autoGrowCollectionLimit

콤비네이션피자라지 2022. 6. 4. 21:24

@InitBinder는 spring web에서 폼값, 입력값등을 바인딩 하는 WebDataBinder 관련 설정을 가능하게 한다.

WebDataBinder 간단 설명

스프링 컨트롤러에 매핑되어 있는 메서드 내에서 object argument로 바인딩하는 역할을 담당한다.
@RequestMapping 되어 있는 모든 메서드에 적용된다.
Initbinder 메서드는 반드시 리턴 값이 없어야 한다.

코드 예시

@RestController
public class ModelAttributeController {

    @PostMapping("/model")
    public boolean getModel(@ModelAttribute RandomCollection randomCollection) {
        return true;
    }

    @Data
    @NoArgsConstructor
    @AllArgsConstructor
    @Validated
    public static class RandomCollection {
        private List<Long> randomCollections;
    }

    @InitBinder
    public void initBinder(WebDataBinder webDataBinder) {
        webDataBinder.setAutoGrowCollectionLimit(255);
    }
}

테스트

그렇다면 설정이 잘 동작하는지 확인하기 위해서, setAutoGrowCollectionLimit을 255로 설정 한 뒤, curl을 이용해서
테스트를 진행해보자.

curl -X 'POST' \
  'http://127.0.0.1:8080/model' \
  -H 'accept: application/json;charset=UTF-8' \
  -H 'Content-Type: application/x-www-form-urlencoded' \
  -d "randomCollections[0]=1&randomCollections[256]=2"

application/x-www-form-urlencoded 타입으로 256 번째 인덱스 값을 실어서 호출하였다.

에러 메시지

{"timestamp":"2022-06-04T11:50:07.454+00:00","status":500,"error":"Internal Server Error","trace":"org.springframework.beans.InvalidPropertyException: Invalid property 'randomCollections[256]' of bean class [com.joohyeok.jeong.spring.controller.ModelAttributeController$RandomCollection]: Invalid list index in property path 'randomCollections[256]'; 
nested exception is java.lang.IndexOutOfBoundsException: Index 256 out of bounds for length 1
\tat org.springframework.beans.AbstractNestablePropertyAccessor.processKeyedProperty(AbstractNestablePropertyAccessor.java:351)
\tat org.springframework.beans.AbstractNestablePropertyAccessor.setPropertyValue(AbstractNestablePropertyAccessor.java:275)
\tat org.springframework.beans.AbstractNestablePropertyAccessor.setPropertyValue(AbstractNestablePropertyAccessor.java:266)
\tat 
org.springframework.beans.AbstractPropertyAccessor.setPropertyValues(AbstractPropertyAccessor.java:104)
\tat org.springframework.validation.DataBinder.applyPropertyValues(DataBinder.java:889)
\tat org.springframework.validation.DataBinder.doBind(DataBinder.java:780)
\tat org.springframework.web.bind.WebDataBinder.doBind(WebDataBinder.java:207)
\tat org.springframework.web.bind.ServletRequestDataBinder.bind(ServletRequestDataBinder.java:129)
\tat org.springframework.web.servlet.mvc.method.annotation.ServletModelAttributeMethodProcessor.bindRequestParameters(ServletModelAttributeMethodProcessor.java:158)
\tat org.springframework.web.method.annotation.ModelAttributeMethodProcessor.resolveArgument(ModelAttributeMethodProcessor.java:171)
\tat org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:122)
\tat org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:179)
\tat org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:146)
\tat org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117)
\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895)
\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808)
\tat org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
\tat org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1067)
\tat org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963)
\tat org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
\tat org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909)
\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:681)
\tat org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:764)
\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227)
\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
\tat org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
\tat org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)
\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)
\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
\tat org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)
\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)
\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
\tat org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)
\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)
\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
\tat org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197)
\tat org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97)
\tat org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541)
\tat org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135)
\tat org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
\tat org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78)
\tat org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:360)
\tat org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399)
\tat org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
\tat org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:890)
\tat org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1743)
\tat org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
\tat org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
\tat org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
\tat org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
\tat java.base/java.lang.Thread.run(Thread.java:833)
Caused by: java.lang.IndexOutOfBoundsException: Index 256 out of bounds for length 1
\tat java.base/jdk.internal.util.Preconditions.outOfBounds(Preconditions.java:64)
\tat java.base/jdk.internal.util.Preconditions.outOfBoundsCheckIndex(Preconditions.java:70)
\tat java.base/jdk.internal.util.Preconditions.checkIndex(Preconditions.java:266)
\tat java.base/java.util.Objects.checkIndex(Objects.java:359)
\tat java.base/java.util.ArrayList.set(ArrayList.java:441)
\tat org.springframework.beans.AbstractNestablePropertyAccessor.processKeyedProperty(AbstractNestablePropertyAccessor.java:348)
\t... 56 more
","message":"Invalid property 'randomCollections[256]' of bean class [com.joohyeok.jeong.spring.controller.ModelAttributeController$RandomCollection]: Invalid list index in property path 'randomCollections[256]'; nested exception is java.lang.IndexOutOfBoundsException: Index 256 out of bounds for length 1","path":"/model"}

복잡한데, 코드를 따라내려가면 다음과 같다.

RequestMappingHandler 가 호출되면서 @ModelAttribute 파라미터를 설정했을 때 위 순서대로 호출이 진행된다.

그렇다면, 우리가 설정한 속성은 언제 적용이 되면서 Exception이 발생하는 걸까?

AbstractNestablePropertyAccessor 내에서, List의 파라미터를 바인딩하는 과정에서 신규로 read한 프로퍼티가 list의 크기보다 크면서, 설정한 autoGrowCollectionLimit보다 낮을 경우에 한 해서 List add 하고, 아닐 경우 이미 생성된 ArrayList에 set하게 된다. 이 때 생성된 리스트의 크기는 설정하려는 index보다 작기 때문에 java.lang.IndexOutOfBoundsException이 발생하게 된다.

발견하기 어려운 속성이며 장애를 맞기 쉬운 설정이다.
이를 막기위해서는 mockMvc를 통한 Junit Controller 테스트가 작성되고, 배포 전 수행되는 CI/CD가 구성되어야 할 것이다.