전역 예외 처리 및 공통 예외 구조 구현

build.gradle.kts

@@ -28,8 +28,8 @@ repositories {
 
 dependencies {
     implementation("org.springframework.boot:spring-boot-starter-data-jpa")
-    implementation("org.springframework.boot:spring-boot-starter-oauth2-client")
-    implementation("org.springframework.boot:spring-boot-starter-security")
+//    implementation("org.springframework.boot:spring-boot-starter-oauth2-client")
+//    implementation("org.springframework.boot:spring-boot-starter-security")
     implementation("org.springframework.boot:spring-boot-starter-validation")
     implementation("org.springframework.boot:spring-boot-starter-web")
     implementation("org.springframework.boot:spring-boot-starter-data-redis")

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();
+	}
+}

src/main/java/com/example/log4u/common/exception/ApiErrorResponse.java

@@ -0,0 +1,29 @@
+package com.example.log4u.common.exception;
+
+import java.util.List;
+
+import org.springframework.validation.FieldError;
+
+import com.fasterxml.jackson.annotation.JsonInclude;
+
+import lombok.Builder;
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+@Getter
+@Builder
+@RequiredArgsConstructor
+public class ApiErrorResponse {
+	private final String errorMessage;
+	private final int errorCode;
+
+	@JsonInclude(JsonInclude.Include.NON_EMPTY)
+	private final List<ValidationError> errors;
+
+	public record ValidationError(String field, String message) {
+
+		public static ValidationError of(final FieldError fieldError) {
+			return new ValidationError(fieldError.getField(), fieldError.getDefaultMessage());
+		}
+	}
+}

src/main/java/com/example/log4u/common/exception/CommonErrorCode.java

@@ -0,0 +1,33 @@
+package com.example.log4u.common.exception;
+
+import org.springframework.http.HttpStatus;
+
+import com.example.log4u.common.exception.base.ErrorCode;
+
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+@Getter
+@RequiredArgsConstructor
+public enum CommonErrorCode implements ErrorCode {
+
+    INVALID_PARAMETER(HttpStatus.BAD_REQUEST, "잘못된 요청입니다"),
+    UNAUTHENTICATED(HttpStatus.UNAUTHORIZED,"로그인이 필요한 기능입니다."),
+    FORBIDDEN(HttpStatus.FORBIDDEN, "접근 권한이 없습니다"),
+    RESOURCE_NOT_FOUND(HttpStatus.NOT_FOUND, "요청 정보를 찾을 수 없습니다"),
+    INTERNAL_SERVER_ERROR(HttpStatus.INTERNAL_SERVER_ERROR, "서버 내부 오류입니다. 관리자에게 문의하세요.")
+    ;
+
+    private final HttpStatus httpStatus;
+    private final String message;
+
+    @Override
+    public HttpStatus getHttpStatus() {
+        return this.httpStatus;
+    }
+
+    @Override
+    public String getErrorMessage() {
+        return this.message;
+    }
+}

src/main/java/com/example/log4u/common/exception/base/ErrorCode.java

@@ -0,0 +1,9 @@
+package com.example.log4u.common.exception.base;
+
+import org.springframework.http.HttpStatus;
+
+public interface ErrorCode {
+    String name();
+    HttpStatus getHttpStatus();
+    String getErrorMessage();
+}

src/main/java/com/example/log4u/common/exception/base/ServiceException.java

@@ -0,0 +1,15 @@
+package com.example.log4u.common.exception.base;
+
+
+import lombok.Getter;
+
+@Getter
+public class ServiceException extends RuntimeException {
+
+    private final ErrorCode errorCode;
+
+    public ServiceException(ErrorCode errorCode) {
+        super(errorCode.getErrorMessage());
+        this.errorCode = errorCode;
+    }
+}

src/main/java/com/example/log4u/common/external/ClientConfig.java

@@ -0,0 +1,18 @@
+package com.example.log4u.common.external;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.web.client.RestTemplate;
+
+import com.example.log4u.common.external.hanlder.ApiResponseErrorHandler;
+
+@Configuration
+public class ClientConfig {
+
+    @Bean
+    public RestTemplate restTemplate() {
+        RestTemplate restTemplate = new RestTemplate();
+        restTemplate.setErrorHandler(new ApiResponseErrorHandler());
+        return restTemplate;
+    }
+}

src/main/java/com/example/log4u/common/external/exception/ExternalApiRequestException.java

@@ -0,0 +1,13 @@
+package com.example.log4u.common.external.exception;
+
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+@Getter
+@RequiredArgsConstructor
+public class ExternalApiRequestException extends RuntimeException{
+
+    private final String statusCode;
+    private final String message;
+
+}

src/main/java/com/example/log4u/common/external/hanlder/ApiResponseErrorHandler.java

@@ -0,0 +1,34 @@
+package com.example.log4u.common.external.hanlder;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.stream.Collectors;
+
+import org.springframework.http.client.ClientHttpResponse;
+import org.springframework.web.client.ResponseErrorHandler;
+
+import com.example.log4u.common.external.exception.ExternalApiRequestException;
+
+import lombok.extern.slf4j.Slf4j;
+
+@Slf4j
+public class ApiResponseErrorHandler implements ResponseErrorHandler {
+    @Override
+    public boolean hasError(ClientHttpResponse response) throws IOException {
+        return !response.getStatusCode().is2xxSuccessful();
+    }
+
+    @Override
+    public void handleError(ClientHttpResponse response) throws IOException {
+        String body;
+        try (BufferedReader reader = new BufferedReader(new InputStreamReader(response.getBody()))) {
+            body = reader.lines().collect(Collectors.joining("\n"));
+        }
+
+        log.error("API 호출 중 에러 발생: HTTP 상태 코드: {}, 응답 본문: {}", response.getStatusCode().value(), body);
+
+        throw new ExternalApiRequestException(response.getStatusCode().toString(),
+                "API 호출 중 에러 발생: " + response.getStatusCode().value() + " 응답 본문: " + body);
+    }
+}

src/main/java/com/example/log4u/domain/comment/exception/CommentErrorCode.java

@@ -0,0 +1,28 @@
+package com.example.log4u.domain.comment.exception;
+
+import org.springframework.http.HttpStatus;
+
+import com.example.log4u.common.exception.base.ErrorCode;
+
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+@Getter
+@RequiredArgsConstructor
+public enum CommentErrorCode implements ErrorCode {
+
+	NOT_FOUND_COMMENT(HttpStatus.NOT_FOUND, "댓글을 찾을 수 없습니다.");
+
+	private final HttpStatus httpStatus;
+	private final String message;
+
+	@Override
+	public HttpStatus getHttpStatus() {
+		return httpStatus;
+	}
+
+	@Override
+	public String getErrorMessage() {
+		return message;
+	}
+}

src/main/java/com/example/log4u/domain/comment/exception/CommentException.java

@@ -0,0 +1,10 @@
+package com.example.log4u.domain.comment.exception;
+
+import com.example.log4u.common.exception.base.ErrorCode;
+import com.example.log4u.common.exception.base.ServiceException;
+
+public class CommentException extends ServiceException {
+	public CommentException(ErrorCode errorCode) {
+		super(errorCode);
+	}
+}

src/main/java/com/example/log4u/domain/comment/exception/NotFoundCommentException.java

@@ -0,0 +1,7 @@
+package com.example.log4u.domain.comment.exception;
+
+public class NotFoundCommentException extends CommentException {
+	public NotFoundCommentException() {
+		super(CommentErrorCode.NOT_FOUND_COMMENT);
+	}
+}

src/main/java/com/example/log4u/domain/comment/testController/TestController.java

@@ -0,0 +1,34 @@
+package com.example.log4u.domain.comment.testController;
+
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.example.log4u.domain.comment.testDto.TestRequest;
+import com.example.log4u.domain.comment.exception.NotFoundCommentException;
+
+import jakarta.validation.Valid;
+
+@RestController
+@RequestMapping("/test")
+public class TestController {
+
+	@PostMapping("/valid")
+	public ResponseEntity<Void> testValidation(@RequestBody @Valid TestRequest request) {
+		return ResponseEntity.ok().build();
+	}
+
+	@GetMapping("/illegal")
+	public String testIllegalArgument() {
+		throw new IllegalArgumentException("잘못된 인자입니다!");
+	}
+
+	@GetMapping("/log4u")
+	public String testLog4uException() {
+		throw new NotFoundCommentException(); // 또는 임의의 ServiceException
+	}
+
+}

src/main/java/com/example/log4u/domain/comment/testDto/TestRequest.java

@@ -0,0 +1,19 @@
+package com.example.log4u.domain.comment.testDto;
+
+// dto/TestRequest.java
+import jakarta.validation.constraints.Min;
+import jakarta.validation.constraints.NotBlank;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+
+@Getter
+@AllArgsConstructor
+public class TestRequest {
+
+	@NotBlank
+	private String name;
+
+	@Min(value = 18, message = "나이는 18세 이상이어야 합니다.")
+	private int age;
+
+}