refactor: API 응답 포맷 통일 및 i18n 키 메시지 적용

src/main/java/com/zimdugo/common/entrypoint/GlobalExceptionHandler.java

@@ -1,76 +1,115 @@
 package com.zimdugo.common.entrypoint;
 
-import com.zimdugo.core.exception.BusinessException;
+import com.zimdugo.core.exception.CustomException;
 import com.zimdugo.core.exception.ErrorCode;
-import com.zimdugo.core.exception.ErrorResponse;
-import jakarta.servlet.http.HttpServletRequest;
-import java.util.Map;
+import com.zimdugo.core.exception.ExternalApiException;
+import com.zimdugo.core.response.RestResponse;
+import com.zimdugo.core.response.ValidationError;
+import jakarta.validation.ConstraintViolationException;
+import java.util.List;
 import lombok.extern.slf4j.Slf4j;
-import org.springframework.http.HttpHeaders;
-import org.springframework.http.HttpStatusCode;
 import org.springframework.http.ResponseEntity;
-import org.springframework.validation.FieldError;
 import org.springframework.web.bind.MethodArgumentNotValidException;
 import org.springframework.web.bind.annotation.ExceptionHandler;
 import org.springframework.web.bind.annotation.RestControllerAdvice;
-import org.springframework.web.context.request.ServletWebRequest;
-import org.springframework.web.context.request.WebRequest;
-import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;
 
 @Slf4j
 @RestControllerAdvice
-public class GlobalExceptionHandler extends ResponseEntityExceptionHandler {
+public class GlobalExceptionHandler {
 
-    @ExceptionHandler(BusinessException.class)
-    public ResponseEntity<Map<String, Object>> handleBusinessException(
-        BusinessException e,
-        HttpServletRequest request
-    ) {
+    @ExceptionHandler(ExternalApiException.class)
+    public ResponseEntity<RestResponse<Void>> handleExternalApiException(ExternalApiException e) {
         ErrorCode errorCode = e.getErrorCode();
-        log.warn("BusinessException: code={}, message={}", errorCode.code(), e.getMessage());
+        log.error("ExternalApiException 발생: code={}, message={}", errorCode.code(), e.getMessage(), e);
         return ResponseEntity.status(errorCode.httpStatus())
-            .body(ErrorResponse.of(errorCode, request.getRequestURI(), e.getMessage()));
+            .body(RestResponse.error(errorCode));
+    }
+
+    @ExceptionHandler(CustomException.class)
+    public ResponseEntity<RestResponse<Void>> handleCustomException(CustomException e) {
+        ErrorCode errorCode = e.getErrorCode();
+        log.warn("CustomException 발생: code={}, message={}", errorCode.code(), e.getMessage());
+        return ResponseEntity.status(errorCode.httpStatus())
+            .body(RestResponse.error(errorCode));
     }
 
     @ExceptionHandler(IllegalArgumentException.class)
-    public ResponseEntity<Map<String, Object>> handleIllegalArgument(
-        IllegalArgumentException e,
-        HttpServletRequest request
-    ) {
-        log.warn("IllegalArgumentException: {}", e.getMessage());
+    public ResponseEntity<RestResponse<Void>> handleIllegalArgumentException(IllegalArgumentException e) {
+        log.warn("IllegalArgumentException 발생: {}", e.getMessage());
+        return ResponseEntity.status(ErrorCode.BAD_REQUEST.httpStatus())
+            .body(RestResponse.error(ErrorCode.BAD_REQUEST));
+    }
+
+    @ExceptionHandler(ConstraintViolationException.class)
+    public ResponseEntity<RestResponse<Void>> handleConstraintViolationException(ConstraintViolationException e) {
+        List<ValidationError> validationErrors = e.getConstraintViolations().stream()
+            .map(violation -> new ValidationError(
+                extractLastPathSegment(violation.getPropertyPath().toString()),
+                toValidationMessage(
+                    violation.getConstraintDescriptor().getAnnotation().annotationType().getSimpleName()
+                )
+            ))
+            .toList();
+
+        log.warn("ConstraintViolationException 발생: {}", e.getMessage());
         return ResponseEntity.status(ErrorCode.BAD_REQUEST.httpStatus())
-            .body(ErrorResponse.of(ErrorCode.BAD_REQUEST, request.getRequestURI(), e.getMessage()));
+            .body(RestResponse.error(
+                ErrorCode.BAD_REQUEST,
+                validationErrors
+            ));
     }
 
     @ExceptionHandler(Exception.class)
-    public ResponseEntity<Map<String, Object>> handleException(
-        Exception e,
-        HttpServletRequest request
-    ) {
+    public ResponseEntity<RestResponse<Void>> handleException(Exception e) {
         log.error("Unhandled exception", e);
         return ResponseEntity.status(ErrorCode.INTERNAL_SERVER_ERROR.httpStatus())
-            .body(ErrorResponse.of(ErrorCode.INTERNAL_SERVER_ERROR, request.getRequestURI()));
+            .body(RestResponse.error(ErrorCode.INTERNAL_SERVER_ERROR));
     }
 
-    @Override
-    protected ResponseEntity<Object> handleMethodArgumentNotValid(
-        MethodArgumentNotValidException ex,
-        HttpHeaders headers,
-        HttpStatusCode status,
-        WebRequest request
-    ) {
-        String message = ex.getBindingResult().getFieldErrors().stream()
-            .findFirst()
-            .map(this::toFieldMessage)
-            .orElse("validation failed");
+    @ExceptionHandler(MethodArgumentNotValidException.class)
+    public ResponseEntity<RestResponse<Void>> handleMethodArgumentNotValid(MethodArgumentNotValidException ex) {
+        List<ValidationError> validationErrors = ex.getBindingResult().getFieldErrors().stream()
+            .map(fieldError -> new ValidationError(
+                fieldError.getField(),
+                toValidationMessage(fieldError.getCode())
+            ))
+            .collect(java.util.stream.Collectors.toCollection(java.util.ArrayList::new));
+        ex.getBindingResult().getGlobalErrors().stream()
+            .map(objectError -> new ValidationError(
+                "global",
+                toValidationMessage(objectError.getCode())
+            ))
+            .forEach(validationErrors::add);
 
-        String path = ((ServletWebRequest) request).getRequest().getRequestURI();
-        log.warn("ValidationException: {}", message);
+        log.warn("MethodArgumentNotValidException 발생");
         return ResponseEntity.status(ErrorCode.BAD_REQUEST.httpStatus())
-            .body(ErrorResponse.of(ErrorCode.BAD_REQUEST, path, message));
+            .body(RestResponse.error(
+                ErrorCode.BAD_REQUEST,
+                validationErrors
+            ));
+    }
+
+    private String extractLastPathSegment(String path) {
+        if (path == null || path.isBlank()) {
+            return "global";
+        }
+
+        int lastDotIndex = path.lastIndexOf('.');
+        if (lastDotIndex >= 0 && lastDotIndex < path.length() - 1) {
+            return path.substring(lastDotIndex + 1);
+        }
+        return path;
     }
 
-    private String toFieldMessage(FieldError fieldError) {
-        return fieldError.getField() + ": " + fieldError.getDefaultMessage();
+    private String toValidationMessage(String rawCode) {
+        if (rawCode == null || rawCode.isBlank()) {
+            return "validation.invalid";
+        }
+
+        String snake = rawCode
+            .replaceAll("([a-z0-9])([A-Z])", "$1_$2")
+            .replace('-', '_')
+            .toLowerCase();
+        return "validation." + snake;
     }
 }

src/main/java/com/zimdugo/common/security/CustomAccessDeniedHandler.java

@@ -2,11 +2,10 @@
 
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.zimdugo.core.exception.ErrorCode;
-import com.zimdugo.core.exception.ErrorResponse;
+import com.zimdugo.core.response.RestResponse;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
 import java.io.IOException;
-import java.util.Map;
 import org.springframework.security.access.AccessDeniedException;
 import org.springframework.security.web.access.AccessDeniedHandler;
 import org.springframework.stereotype.Component;
@@ -28,7 +27,7 @@ public void handle(
         response.setContentType(APPLICATION_JSON);
         response.setCharacterEncoding(UTF_8);
 
-        Map<String, Object> body = ErrorResponse.of(ErrorCode.FORBIDDEN, request.getRequestURI());
+        RestResponse<Void> body = RestResponse.error(ErrorCode.FORBIDDEN);
 
         response.getWriter().write(objectMapper.writeValueAsString(body));
     }

src/main/java/com/zimdugo/common/security/CustomAuthenticationEntryPoint.java

@@ -2,11 +2,10 @@
 
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.zimdugo.core.exception.ErrorCode;
-import com.zimdugo.core.exception.ErrorResponse;
+import com.zimdugo.core.response.RestResponse;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
 import java.io.IOException;
-import java.util.Map;
 import org.springframework.security.core.AuthenticationException;
 import org.springframework.security.web.AuthenticationEntryPoint;
 import org.springframework.stereotype.Component;
@@ -28,7 +27,7 @@ public void commence(
         response.setContentType(APPLICATION_JSON);
         response.setCharacterEncoding(UTF_8);
 
-        Map<String, Object> body = ErrorResponse.of(ErrorCode.UNAUTHORIZED, request.getRequestURI());
+        RestResponse<Void> body = RestResponse.error(ErrorCode.UNAUTHORIZED);
 
         response.getWriter().write(objectMapper.writeValueAsString(body));
     }

src/main/java/com/zimdugo/core/exception/BusinessException.java

@@ -1,15 +1,16 @@
 package com.zimdugo.core.exception;
 
-public class BusinessException extends RuntimeException {
-
-    private final ErrorCode errorCode;
+public class BusinessException extends CustomException {
 
     public BusinessException(ErrorCode errorCode) {
-        super(errorCode.message());
-        this.errorCode = errorCode;
+        super(errorCode);
+    }
+
+    public BusinessException(ErrorCode errorCode, String message) {
+        super(errorCode, message);
     }
 
-    public ErrorCode getErrorCode() {
-        return errorCode;
+    public BusinessException(ErrorCode errorCode, String message, Throwable cause) {
+        super(errorCode, message, cause);
     }
 }

src/main/java/com/zimdugo/core/exception/CustomException.java

@@ -0,0 +1,25 @@
+package com.zimdugo.core.exception;
+
+import lombok.Getter;
+
+@Getter
+public class CustomException extends RuntimeException {
+
+    private final ErrorCode errorCode;
+
+    public CustomException(ErrorCode errorCode) {
+        super(errorCode.getMessage());
+        this.errorCode = errorCode;
+    }
+
+    public CustomException(ErrorCode errorCode, String message) {
+        super(message);
+        this.errorCode = errorCode;
+    }
+
+    public CustomException(ErrorCode errorCode, String message, Throwable cause) {
+        super(message, cause);
+        this.errorCode = errorCode;
+    }
+
+}

src/main/java/com/zimdugo/core/exception/ErrorCode.java

@@ -1,24 +1,36 @@
 package com.zimdugo.core.exception;
 
+import com.zimdugo.core.response.BaseCode;
+import lombok.Getter;
 import org.springframework.http.HttpStatus;
 
-public enum ErrorCode {
-    BAD_REQUEST("C400", "bad request", HttpStatus.BAD_REQUEST),
-    UNAUTHORIZED("C401", "unauthorized", HttpStatus.UNAUTHORIZED),
-    FORBIDDEN("C403", "forbidden", HttpStatus.FORBIDDEN),
-    NOT_FOUND("C404", "resource not found", HttpStatus.NOT_FOUND),
-    INTERNAL_SERVER_ERROR("C500", "internal server error", HttpStatus.INTERNAL_SERVER_ERROR),
-
-    REFRESH_TOKEN_NOT_FOUND("A4001", "refresh token not found", HttpStatus.BAD_REQUEST),
-    INVALID_REFRESH_TOKEN("A4002", "invalid refresh token", HttpStatus.BAD_REQUEST),
-    REFRESH_TOKEN_MISMATCH("A4003", "refresh token mismatch", HttpStatus.BAD_REQUEST),
-    REFRESH_TOKEN_REVOKED("A4004", "refresh token revoked", HttpStatus.BAD_REQUEST),
-    USER_NOT_FOUND("U4041", "user not found", HttpStatus.NOT_FOUND),
-    USER_ALREADY_WITHDRAWN("U4002", "user already withdrawn", HttpStatus.BAD_REQUEST),
-    UNSUPPORTED_SOCIAL_LOGIN("A4005", "unsupported social login provider", HttpStatus.BAD_REQUEST),
-    AUTHENTICATED_USER_NOT_FOUND("A4011", "authenticated user not found", HttpStatus.UNAUTHORIZED);
+public enum ErrorCode implements BaseCode {
+    BAD_REQUEST("C400", "common.bad_request", HttpStatus.BAD_REQUEST),
+    UNAUTHORIZED("C401", "common.unauthorized", HttpStatus.UNAUTHORIZED),
+    FORBIDDEN("C403", "common.forbidden", HttpStatus.FORBIDDEN),
+    NOT_FOUND("C404", "common.not_found", HttpStatus.NOT_FOUND),
+    INTERNAL_SERVER_ERROR("C500", "common.internal_server_error", HttpStatus.INTERNAL_SERVER_ERROR),
 
+
+    REFRESH_TOKEN_NOT_FOUND("A4001", "auth.refresh_token_not_found", HttpStatus.BAD_REQUEST),
+    INVALID_REFRESH_TOKEN("A4002", "auth.invalid_refresh_token", HttpStatus.BAD_REQUEST),
+    REFRESH_TOKEN_MISMATCH("A4003", "auth.refresh_token_mismatch", HttpStatus.BAD_REQUEST),
+    REFRESH_TOKEN_REVOKED("A4004", "auth.refresh_token_revoked", HttpStatus.BAD_REQUEST),
+
+
+    EXTERNAL_API_ERROR("E5021", "external.api_error", HttpStatus.BAD_GATEWAY),
+
+
+    USER_NOT_FOUND("U4041", "user.not_found", HttpStatus.NOT_FOUND),
+    USER_ALREADY_WITHDRAWN("U4002", "user.already_withdrawn", HttpStatus.BAD_REQUEST),
+
+
+    UNSUPPORTED_SOCIAL_LOGIN("A4005", "auth.unsupported_social_login", HttpStatus.BAD_REQUEST),
+    AUTHENTICATED_USER_NOT_FOUND("A4011", "auth.authenticated_user_not_found", HttpStatus.UNAUTHORIZED);
+
+    @Getter
     private final String code;
+    @Getter
     private final String message;
     private final HttpStatus httpStatus;
 
@@ -39,4 +51,8 @@ public String message() {
     public HttpStatus httpStatus() {
         return httpStatus;
     }
+
+    public HttpStatus getStatus() {
+        return httpStatus;
+    }
 }

src/main/java/com/zimdugo/core/exception/ExternalApiException.java

@@ -0,0 +1,12 @@
+package com.zimdugo.core.exception;
+
+public class ExternalApiException extends CustomException {
+
+    public ExternalApiException(String message) {
+        super(ErrorCode.EXTERNAL_API_ERROR, message);
+    }
+
+    public ExternalApiException(String message, Throwable cause) {
+        super(ErrorCode.EXTERNAL_API_ERROR, message, cause);
+    }
+}

src/main/java/com/zimdugo/core/response/BaseCode.java

@@ -0,0 +1,11 @@
+package com.zimdugo.core.response;
+
+import org.springframework.http.HttpStatus;
+
+public interface BaseCode {
+    String getCode();
+
+    String getMessage();
+
+    HttpStatus getStatus();
+}