[SPRING] Page RestTemplate 파싱오류 > PageImpl 구현체

• gateway-api
  • 외부 or 프론트 수신 프로젝트
• core-api
  • db 처리 및 코어 로직 프로젝트
  • 외부에서 접근 X
  • 외부용 api에서만 접근하도록 구성 됨
• 구성 (resttemplate 사용)
  • 요청 gateway-api >> core-api
  • 응답 gateway-api << core-api

[문제사항]

gateway-api 응답받는 과정에서 Page<Dto> 파싱 오류 발생

@Override
public Page<Dto> getAdminCountrySafetyPage(final RequestApiArgBuilder argBuilder) {
    return dcrOtisApiClient.get(argBuilder, new ParameterizedTypeReference<Page<Dto>>() {
    }).getData();
}

[오류]

"org.springframework.http.converter.HttpMessageConversionException: Type definition error: [simple type, class org.springframework.data.domain.Page]; nested exception is com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `org.springframework.data.domain.Page` (no Creators, like default constructor, exist): abstract types either need to be mapped to concrete types, have custom deserializer, or contain additional type information\\n at [Source: (ByteArrayInputStream); line: 1, column: 57] (through reference chain: com.hanatour.dcr.core.servlet.dto.HntApiResponse[\\"data\\"])\\n\\tat org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.readJavaType(AbstractJackson2HttpMessageConverter.java:386)\\n\\tat org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.read(AbstractJackson2HttpMessageConverter.java:342)\\n\\tat org.springframework.web.client.HttpMessageConverterExtractor.extractData(HttpMessageConverterExtractor.java:105)\\n\\tat org.springframework.web.client.RestTemplate$ResponseEntityResponseExtractor.extractData(RestTemplate.java:1037)\\n\\tat org.springframework.web.client.RestTemplate$ResponseEntityResponseExtractor.extractData(RestTemplate.java:1020)\\n\\tat org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:778)\\n\\tat org.springframework.web.client.RestTemplate.execute(RestTemplate.java:751)\\n\\tat org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:651)\\n\\tat com.hanatour.dcr.core.apiclient.AbstractApiClient.exchange(AbstractApiClient.java:234)\\n\\tat com.hanatour.dcr.core.apiclient.AbstractApiClient.getForEntity(AbstractApiClient.java:89)\\n\\tat com.hanatour.dcr.core.apiclient.AbstractApiClient.get(AbstractApiClient.java:66)\\n\\tat com.hanatour.dcr.adminapi.otisapi.service.impl.CountrySafetyServiceImpl.getAdminCountrySafetyPage(CountrySafetyServiceImpl.java:40)\\n\\tat com.hanatour.dcr.adminapi.otisapi.controller.CountrySafetyController.getAdminCountrySafety(CountrySafetyController.java:59)\\n\\tat java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\\n\\tat java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\\n\\tat java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\\n\\tat java.base/java.lang.reflect.Method.invoke(Method.java:566)\\n\\tat org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205)\\n\\tat org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:150)\\n\\tat org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117)\\n\\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895)\\n\\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808)\\n\\tat org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)\\n\\tat org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1067)\\n\\tat org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963)\\n\\tat org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)\\n\\tat org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)\\n\\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:655)\\n\\tat org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)\\n\\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:764)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)\\n\\tat org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)\\n\\tat com.hanatour.dcr.core.servlet.filter.LoggingFilter.doFilter(LoggingFilter.java:27)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)\\n\\tat org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:204)\\n\\tat org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:183)\\n\\tat org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:354)\\n\\tat org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:267)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)\\n\\tat org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)\\n\\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)\\n\\tat org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)\\n\\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)\\n\\tat org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:96)\\n\\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)\\n\\tat org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)\\n\\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)\\n\\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)\\n\\tat org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197)\\n\\tat org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97)\\n\\tat org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:540)\\n\\tat org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135)\\n\\tat org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)\\n\\tat org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78)\\n\\tat org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:357)\\n\\tat org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:382)\\n\\tat org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)\\n\\tat org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:895)\\n\\tat org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1732)\\n\\tat org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)\\n\\tat org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)\\n\\tat org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)\\n\\tat org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)\\n\\tat java.base/java.lang.Thread.run(Thread.java:829)\\nCaused by: com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `org.springframework.data.domain.Page` (no Creators, like default constructor, exist): abstract types either need to be mapped to concrete types, have custom deserializer, or contain additional type information\\n at [Source: (ByteArrayInputStream); line: 1, column: 57] (through reference chain: com.hanatour.dcr.core.servlet.dto.HntApiResponse[\\"data\\"])\\n\\tat com.fasterxml.jackson.databind.exc.InvalidDefinitionException.from(InvalidDefinitionException.java:67)\\n\\tat com.fasterxml.jackson.databind.DeserializationContext.reportBadDefinition(DeserializationContext.java:1904)\\n\\tat com.fasterxml.jackson.databind.DatabindContext.reportBadDefinition(DatabindContext.java:400)\\n\\tat com.fasterxml.jackson.databind.DeserializationContext.handleMissingInstantiator(DeserializationContext.java:1349)\\n\\tat com.fasterxml.jackson.databind.deser.AbstractDeserializer.deserialize(AbstractDeserializer.java:274)\\n\\tat com.fasterxml.jackson.databind.deser.impl.FieldProperty.deserializeAndSet(FieldProperty.java:138)\\n\\tat com.fasterxml.jackson.databind.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:391)\\n\\tat com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:184)\\n\\tat com.fasterxml.jackson.databind.deser.DefaultDeserializationContext.readRootValue(DefaultDeserializationContext.java:322)\\n\\tat com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:4674)\\n\\tat com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3682)\\n\\tat org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.readJavaType(AbstractJackson2HttpMessageConverter.java:378)\\n\\t... 75 more\\n",
    "message": "Type definition error: [simple type, class org.springframework.data.domain.Page]; nested exception is com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `org.springframework.data.domain.Page` (no Creators, like default constructor, exist): abstract types either need to be mapped to concrete types, have custom deserializer, or contain additional type information\\n at [Source: (ByteArrayInputStream); line: 1, column: 57] (through reference chain: com.hanatour.dcr.core.servlet.dto.HntApiResponse[\\"data\\"])"

간략하게 설명하자면

이 문제는 Jackson이 추상 유형을 인스턴스화할 수 없다는 것입니다.

구체적인 유형으로 Page를 인스턴스화하는 방법에 대한 정보를 Jackson에게 제공해야 합니다. 그러나 구체적인 유형인 PageImpl에는 기본 생성자나 해당 문제에 대한 @JsonCreators가 없으므로 다음 코드도 사용할 수 없습니다.

[해결]

추상화 객체에 대해서 @JsonCreators 구현체를 생성함

public class CustomPageImpl<T> extends PageImpl<T> {

    @JsonCreator(mode = JsonCreator.Mode.PROPERTIES)
    public CustomPageImpl(@JsonProperty("content") List<T> content,
                        @JsonProperty("number") int number,
                        @JsonProperty("size") int size,
                        @JsonProperty("totalElements") Long totalElements,
                        @JsonProperty("pageable") JsonNode pageable,
                        @JsonProperty("last") boolean last,
                        @JsonProperty("totalPages") int totalPages,
                        @JsonProperty("sort") JsonNode sort,
                        @JsonProperty("first") boolean first,
                        @JsonProperty("numberOfElements") int numberOfElements) {

        super(content, PageRequest.of(number, size), totalElements);
    }

    public CustomPageImpl(List<T> content, Pageable pageable, long total) {
        super(content, pageable, total);
    }

    public CustomPageImpl(List<T> content) {
        super(content);
    }

    public CustomPageImpl() {
        super(new ArrayList<>());
    }
}

수정항목 반영

@Override
public Page<Dto> getAdminCountrySafetyPage(final RequestApiArgBuilder argBuilder) {
    return dcrOtisApiClient.get(argBuilder, new ParameterizedTypeReference<CustomPageImpl<Dto>>() {
    }).getData();
}

반영 후 제대로 파싱되어 오류없이 응답 성공!