kakao token 발급 시 에러

Question

안녕하세요 ! 강의 수강 중에 에러난 부분이 해결되지 않아 질문 남깁니다. 지금 '카카오 토큰 발급 구현(2) - 토큰 받기' 강의 마지막까지 코드 작성 후 api 실행 했는데 결과 {"errorCode":"500 INTERNAL_SERVER_ERROR","errorMessage":"Could not extract response: no suitable HttpMessageConverter found for response type [class com.app.web.kakaotoken.dto.KakaoTokenDto$Response] and content type [text/html]"} 로 나오고 있습니다. 콘솔창의 에러는 feign.codec.DecodeException: Could not extract response: no suitable HttpMessageConverter found for response type [class com.app.web.kakaotoken.dto.KakaoTokenDto$Response] and content type [text/html] at feign.InvocationContext.proceed(InvocationContext.java:40) ~[feign-core-11.10.jar:na] at feign.AsyncResponseHandler.decode(AsyncResponseHandler.java:116) ~[feign-core-11.10.jar:na] at feign.AsyncResponseHandler.handleResponse(AsyncResponseHandler.java:89) ~[feign-core-11.10.jar:na] at feign.SynchronousMethodHandler.executeAndDecode(SynchronousMethodHandler.java:141) ~[feign-core-11.10.jar:na] at feign.SynchronousMethodHandler.invoke(SynchronousMethodHandler.java:91) ~[feign-core-11.10.jar:na] at feign.ReflectiveFeign$FeignInvocationHandler.invoke(ReflectiveFeign.java:100) ~[feign-core-11.10.jar:na] at com.sun.proxy.$Proxy109.requestKakaoToken(Unknown Source) ~[na:na] at com.app.web.kakaotoken.controller.KakaoTokenController.loginCallback(KakaoTokenController.java:39) ~[main/:na] at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na] at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na] at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na] at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[na:na] at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) ~[spring-web-5.3.20.jar:5.3.20] at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:150) ~[spring-web-5.3.20.jar:5.3.20] at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117) ~[spring-webmvc-5.3.20.jar:5.3.20] at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895) ~[spring-webmvc-5.3.20.jar:5.3.20] at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808) ~[spring-webmvc-5.3.20.jar:5.3.20] at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.3.20.jar:5.3.20] at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1067) ~[spring-webmvc-5.3.20.jar:5.3.20] at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963) ~[spring-webmvc-5.3.20.jar:5.3.20] at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.3.20.jar:5.3.20] at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) ~[spring-webmvc-5.3.20.jar:5.3.20] at javax.servlet.http.HttpServlet.service(HttpServlet.java:655) ~[tomcat-embed-core-9.0.63.jar:4.0.FR] at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.3.20.jar:5.3.20] at javax.servlet.http.HttpServlet.service(HttpServlet.java:764) ~[tomcat-embed-core-9.0.63.jar:4.0.FR] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.63.jar:9.0.63] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-5.3.20.jar:5.3.20] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.20.jar:5.3.20] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-5.3.20.jar:5.3.20] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.20.jar:5.3.20] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-5.3.20.jar:5.3.20] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.20.jar:5.3.20] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:360) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:890) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1743) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-embed-core-9.0.63.jar:9.0.63] at java.base/java.lang.Thread.run(Thread.java:829) ~[na:na] Caused by: org.springframework.web.client.UnknownContentTypeException: Could not extract response: no suitable HttpMessageConverter found for response type [class com.app.web.kakaotoken.dto.KakaoTokenDto$Response] and content type [text/html] at org.springframework.web.client.HttpMessageConverterExtractor.extractData(HttpMessageConverterExtractor.java:126) ~[spring-web-5.3.20.jar:5.3.20] at org.springframework.cloud.openfeign.support.SpringDecoder.decode(SpringDecoder.java:75) ~[spring-cloud-openfeign-core-3.1.8.jar:3.1.8] at org.springframework.cloud.openfeign.support.ResponseEntityDecoder.decode(ResponseEntityDecoder.java:61) ~[spring-cloud-openfeign-core-3.1.8.jar:3.1.8] at feign.optionals.OptionalDecoder.decode(OptionalDecoder.java:36) ~[feign-core-11.10.jar:na] at feign.InvocationContext.proceed(InvocationContext.java:36) ~[feign-core-11.10.jar:na] ... 57 common frames omitted     코드를 여러 번 봐도 강사님이랑 다른 부분이 없는 거 같아서 여쭤봅니다. 감사합니다 !!

구파고 · Answer

에러를 다시 보니깐 KakaoTokenClient로 카카오 토큰을 받아올 때 변환이 안되서 그렇군요! Response의 contentType을 text/html 로 인식하는거 같네요 혹시 모르니 코드도 복사해서 붙여 넣어보시면 좋을꺼 같습니다. @GetMapping("/oauth/kakao/callback") public @ResponseBody String loginCallback(String code) { String contentType = "application/x-www-form-urlencoded;charset=utf-8"; KakaoTokenDto.Request kakaoTokenRequestDto = KakaoTokenDto.Request.builder() .client_id(clientId) .client_secret(clientSecret) .grant_type("authorization_code") .code(code) .redirect_uri("http://localhost:8080/oauth/kakao/callback") .build(); KakaoTokenDto.Response kakaoToken = kakaoTokenClient.requestKakaoToken(contentType, kakaoTokenRequestDto); return "kakao toekn : " + kakaoToken; }   KakaoTokenClient @FeignClient(url = "https://kauth.kakao.com", name = "kakaoTokenClient") public interface KakaoTokenClient { @PostMapping(value = "/oauth/token", consumes = "application/json") KakaoTokenDto.Response requestKakaoToken(@RequestHeader("Content-Type") String contentType, @SpringQueryMap KakaoTokenDto.Request request ); } KakaoTokenDto의 Response에서 기본생성자가 없을 경우 오류가 발생하시는 분들도 있으셔서 @NoArgsConstructor와 @AllArgsConstructor도 한번 추가해 보시면 좋을꺼 같습니다. public class KakaoTokenDto { @ToString @Builder @Getter @NoArgsConstructor @AllArgsConstructor public static class Response { private String token_type; private String access_token; private Integer expires_in; private String refresh_token; private Integer refresh_token_expires_in; private String scope; } }

구파고 · Answer

안녕하세요! 혹시 @ResponseBody가 빠졌는지 확인해보시면 좋을꺼 같네요. 에러메세지를 보면 text/html을 찾을 수 없다 이런식으로 나오는데 loginCallback에서는 json을 클라이언트로 반환해줘야합니다. public @ResponseBody String loginCallback(String code) {