feat: 전역 예외 처리 클래스(GlobalExceptionHandler) 구현

Author: dnzp75

src/main/java/com/example/log4u/common/advice/GlobalExceptionHandler.java

@@ -0,0 +1,114 @@
+package com.example.log4u.common.advice;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatusCode;
+import org.springframework.http.ResponseEntity;
+import org.springframework.lang.NonNull;
+import org.springframework.validation.BindException;
+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;
+
+import com.example.log4u.common.exception.ApiErrorResponse;
+import com.example.log4u.common.exception.CommonErrorCode;
+import com.example.log4u.common.exception.base.ErrorCode;
+import com.example.log4u.common.exception.base.ServiceException;
+
+import jakarta.servlet.http.HttpServletRequest;
+import lombok.extern.slf4j.Slf4j;
+
+@RestControllerAdvice
+@Slf4j
+public class GlobalExceptionHandler extends ResponseEntityExceptionHandler {
+
+	@Override
+	public ResponseEntity<Object> handleMethodArgumentNotValid(
+		MethodArgumentNotValidException e,
+		@NonNull HttpHeaders headers,
+		@NonNull HttpStatusCode status,
+		@NonNull WebRequest request) {
+		HttpServletRequest servletRequest = ((ServletWebRequest)request).getRequest();
+
+		String requestUrl = servletRequest.getRequestURI();
+		String httpMethod = servletRequest.getMethod();
+		List<String> errors = e.getBindingResult()
+			.getFieldErrors()
+			.stream()
+			.map(fieldError -> fieldError.getField() + ": " + fieldError.getDefaultMessage())
+			.collect(Collectors.toList());
+
+		log.warn("Validation failed for request to {} {}. Errors: {}",
+			httpMethod, requestUrl, errors);
+		CommonErrorCode errorCode = CommonErrorCode.INVALID_PARAMETER;
+		return handleExceptionInternal(e, errorCode);
+	}
+
+	@ExceptionHandler(IllegalArgumentException.class)
+	public ResponseEntity<ApiErrorResponse> handleIllegalArgument(IllegalArgumentException e) {
+		String location = getExceptionLocation(e);
+
+		log.warn("Illegal argument encountered at {}: {}", location, e.getMessage());
+
+		CommonErrorCode errorCode = CommonErrorCode.INVALID_PARAMETER;
+		return handleExceptionInternal(errorCode);
+	}
+
+	@ExceptionHandler(ServiceException.class)
+	public ResponseEntity<ApiErrorResponse> handleGiveMeTiConException(ServiceException e) {
+		String location = getExceptionLocation(e);
+		log.warn("Error invoke in our app at {}: {} ErrorCode: {}", location, e.getMessage(), e.getErrorCode());
+		ErrorCode errorCode = e.getErrorCode();
+		return handleExceptionInternal(errorCode);
+	}
+
+	@ExceptionHandler({Exception.class})
+	public ResponseEntity<ApiErrorResponse> handleAllException(Exception e) {
+		String location = getExceptionLocation(e);
+		log.warn("Unhandled exception occurred at {}: {}", location, e.getMessage());
+
+		CommonErrorCode errorCode = CommonErrorCode.INTERNAL_SERVER_ERROR;
+		return handleExceptionInternal(errorCode);
+	}
+
+	private ResponseEntity<ApiErrorResponse> handleExceptionInternal(ErrorCode errorCode) {
+		return ResponseEntity.status(errorCode.getHttpStatus())
+			.body(makeErrorResponse(errorCode));
+	}
+
+	private ApiErrorResponse makeErrorResponse(ErrorCode errorCode) {
+		return ApiErrorResponse.builder()
+			.errorMessage(errorCode.getErrorMessage())
+			.errorCode(errorCode.getHttpStatus().value())
+			.build();
+	}
+
+	private ResponseEntity<Object> handleExceptionInternal(BindException e, ErrorCode errorCode) {
+		return ResponseEntity.status(errorCode.getHttpStatus())
+			.body(makeErrorResponse(e, errorCode));
+	}
+
+	private ApiErrorResponse makeErrorResponse(BindException e, ErrorCode errorCode) {
+		List<ApiErrorResponse.ValidationError> validationErrorList = e.getBindingResult()
+			.getFieldErrors()
+			.stream()
+			.map(ApiErrorResponse.ValidationError::of)
+			.collect(Collectors.toList());
+
+		return ApiErrorResponse.builder()
+            .errorMessage(errorCode.getErrorMessage())
+            .errorCode(errorCode.getHttpStatus().value())
+			.errors(validationErrorList)
+			.build();
+	}
+
+	private String getExceptionLocation(Exception e) {
+		StackTraceElement element = e.getStackTrace()[0];
+		return element.getClassName() + "." + element.getMethodName() + ":" + element.getLineNumber();
+	}
+}