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Author: KodaiD

core/src/main/java/com/scalar/db/storage/objectstorage/cloudstorage/CloudStorageWrapper.java

@@ -26,7 +26,9 @@
 
 @ThreadSafe
 public class CloudStorageWrapper implements ObjectStorageWrapper {
+  // Batch API has a limit of 100 operations per request
   public static final int BATCH_DELETE_SIZE_LIMIT = 100;
+
   private final Storage storage;
   private final String bucket;
   private final Integer parallelUploadBlockSizeInBytes;

core/src/main/java/com/scalar/db/storage/objectstorage/s3/S3Wrapper.java

@@ -35,7 +35,9 @@
 
 @ThreadSafe
 public class S3Wrapper implements ObjectStorageWrapper {
+  // DeleteObjects API has a limit of 1000 objects per request
   public static final int BATCH_DELETE_SIZE_LIMIT = 1000;
+
   private final S3AsyncClient client;
   private final String bucket;
 
@@ -281,8 +283,12 @@ public void deleteByPrefix(String prefix) throws ObjectStorageWrapperException {
   }
 
   @Override
-  public void close() {
-    client.close();
+  public void close() throws ObjectStorageWrapperException {
+    try {
+      client.close();
+    } catch (Exception e) {
+      throw new ObjectStorageWrapperException("Failed to close the storage wrapper", e);
+    }
   }
 
   private Optional<S3Exception> findS3Exception(Throwable throwable) {

core/src/test/java/com/scalar/db/storage/objectstorage/cloudstorage/CloudStorageWrapperTest.java

@@ -424,6 +424,8 @@ public void deleteByPrefix_StorageExceptionThrown_ShouldThrowObjectStorageWrappe
 
   @Test
   public void close_ShouldCloseTheStorage() throws Exception {
+    // Arrange
+
     // Act
     wrapper.close();
 

core/src/test/java/com/scalar/db/storage/objectstorage/s3/S3WrapperTest.java

@@ -552,7 +552,7 @@ public void deleteByPrefix_S3ExceptionThrown_ShouldThrowObjectStorageWrapperExce
   }
 
   @Test
-  public void close_ShouldCloseTheClient() {
+  public void close_ShouldCloseTheClient() throws Exception {
     // Arrange
 
     // Act