feat: RestTemplate용 ResponseErrorHandler 및 설정 클래스 추가

Author: dnzp75

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/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);
+    }
+}