[BE] 이미지 병렬 업로드 기능 추가

server/src/main/java/server/haengdong/application/ImageService.java

@@ -6,12 +6,14 @@
 import java.io.InputStream;
 import java.util.List;
 import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.stereotype.Service;
 import org.springframework.web.multipart.MultipartFile;
-import server.haengdong.application.response.ImageNameAppResponse;
 import server.haengdong.exception.HaengdongErrorCode;
 import server.haengdong.exception.HaengdongException;
 import software.amazon.awssdk.services.s3.S3Client;
@@ -30,18 +32,26 @@ public class ImageService {
     private String directoryPath;
 
     private final S3Client s3Client;
+    private final ExecutorService executorService;
 
     public List<String> uploadImages(List<MultipartFile> images) {
-        return images.stream()
-                .map(this::uploadImage)
+        List<CompletableFuture<String>> futures = images.stream()
+                .map(image -> CompletableFuture.supplyAsync(() -> uploadImage(image), executorService))
                 .toList();
+
+        CompletableFuture<List<String>> result = CompletableFuture.allOf(futures.toArray(new CompletableFuture[futures.size()]))
+                .thenApply(v -> futures.stream()
+                        .map(this::getFuture)
+                        .toList());
+
+        return result.join();
     }
 
     private String uploadImage(MultipartFile image) {
         try (InputStream inputStream = image.getInputStream()) {
             return uploadImageToStorage(inputStream, image);
         } catch (IOException e) {
-            throw new HaengdongException(HaengdongErrorCode.IMAGE_UPLOAD_FAIL);
+            throw new HaengdongException(HaengdongErrorCode.IMAGE_UPLOAD_FAIL, e);
         }
     }
 
@@ -61,6 +71,14 @@ private String uploadImageToStorage(InputStream inputStream, MultipartFile image
         return imageName;
     }
 
+    private String getFuture(CompletableFuture<String> future) {
+        try {
+            return future.get();
+        } catch (InterruptedException | ExecutionException e) {
+            throw new HaengdongException(HaengdongErrorCode.IMAGE_UPLOAD_FAIL, e);
+        }
+    }
+
     public void deleteImage(String imageName) {
         DeleteObjectRequest deleteObjectRequest = DeleteObjectRequest.builder()
                 .bucket(bucketName)

server/src/main/java/server/haengdong/config/S3Config.java

@@ -1,5 +1,7 @@
 package server.haengdong.config;
 
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import software.amazon.awssdk.regions.Region;
@@ -8,10 +10,17 @@
 @Configuration
 public class S3Config {
 
+    private static final int THREAD_POOL_SIZE = 10;
+
     @Bean
     public S3Client s3Client() {
         return S3Client.builder()
                 .region(Region.AP_NORTHEAST_2)
                 .build();
     }
+
+    @Bean
+    public ExecutorService executorService() {
+        return Executors.newFixedThreadPool(THREAD_POOL_SIZE);
+    }
 }

server/src/main/java/server/haengdong/exception/HaengdongException.java

@@ -16,4 +16,9 @@ public HaengdongException(HaengdongErrorCode errorCode, Object... args) {
         super(String.format(errorCode.getMessage(), args));
         this.errorCode = errorCode;
     }
+
+    public HaengdongException(HaengdongErrorCode errorCode, Throwable cause) {
+        super(errorCode.getMessage(), cause);
+        this.errorCode = errorCode;
+    }
 }