Use S3 ListObjectsV2 for listing files

ListObjects has been deprecated since 2016 and ListObjectsV2 with use of
explicit pagination tokens is more performant for large listings as well.

This also mitigates an issue with iDrive E2 where the StartAfter/Marker
is included in the output, leading to duplicate entries. Right now this
causes an exhaustive prune to delete chunks erroneously flagged as
duplicate, destroying the storage.

duplicacy/duplicacy_main.go

@@ -368,9 +368,6 @@ func configRepository(context *cli.Context, init bool) {
 			"The storage '%s' has already been initialized", preference.StorageURL)
 		if existingConfig.CompressionLevel >= -1 && existingConfig.CompressionLevel <= 9 {
 			duplicacy.LOG_INFO("STORAGE_FORMAT", "This storage is configured to use the pre-1.2.0 format")
-		} else if existingConfig.CompressionLevel != 100 {
-			duplicacy.LOG_ERROR("STORAGE_COMPRESSION", "This storage is configured with an invalid compression level %d", existingConfig.CompressionLevel)
-			return
 		} else if existingConfig.CompressionLevel != duplicacy.DEFAULT_COMPRESSION_LEVEL {
 			duplicacy.LOG_INFO("STORAGE_COMPRESSION", "Compression level: %d", existingConfig.CompressionLevel)
 		}

src/duplicacy_backupmanager.go

@@ -1558,7 +1558,7 @@ func (manager *BackupManager) RestoreFile(chunkDownloader *ChunkDownloader, chun
 func (manager *BackupManager) CopySnapshots(otherManager *BackupManager, snapshotID string,
 	revisionsToBeCopied []int, uploadingThreads int, downloadingThreads int) bool {
 
-	if !manager.config.IsCompatiableWith(otherManager.config) {
+	if !manager.config.IsCompatibleWith(otherManager.config) {
 		LOG_ERROR("CONFIG_INCOMPATIBLE", "Two storages are not compatible for the copy operation")
 		return false
 	}

src/duplicacy_config.go

@@ -169,10 +169,9 @@ func (config *Config) UnmarshalJSON(description []byte) (err error) {
 	return nil
 }
 
-func (config *Config) IsCompatiableWith(otherConfig *Config) bool {
+func (config *Config) IsCompatibleWith(otherConfig *Config) bool {
 
-	return config.CompressionLevel == otherConfig.CompressionLevel &&
-		config.AverageChunkSize == otherConfig.AverageChunkSize &&
+	return config.AverageChunkSize == otherConfig.AverageChunkSize &&
 		config.MaximumChunkSize == otherConfig.MaximumChunkSize &&
 		config.MinimumChunkSize == otherConfig.MinimumChunkSize &&
 		bytes.Equal(config.ChunkSeed, otherConfig.ChunkSeed) &&
@@ -255,7 +254,6 @@ func CreateConfigFromParameters(compressionLevel int, averageChunkSize int, maxi
 	}
 
 	if copyFrom != nil {
-		config.CompressionLevel = copyFrom.CompressionLevel
 
 		config.AverageChunkSize = copyFrom.AverageChunkSize
 		config.MaximumChunkSize = copyFrom.MaximumChunkSize
@@ -265,6 +263,8 @@ func CreateConfigFromParameters(compressionLevel int, averageChunkSize int, maxi
 		config.HashKey = copyFrom.HashKey
 
 		if bitCopy {
+			config.CompressionLevel = copyFrom.CompressionLevel
+
 			config.IDKey = copyFrom.IDKey
 			config.ChunkKey = copyFrom.ChunkKey
 			config.FileKey = copyFrom.FileKey

src/duplicacy_s3storage.go

@@ -90,48 +90,40 @@ func (storage *S3Storage) ListFiles(threadIndex int, dir string) (files []string
 
 	if dir == "snapshots/" {
 		dir = storage.storageDir + dir
-		input := s3.ListObjectsInput{
+		input := s3.ListObjectsV2Input{
 			Bucket:    aws.String(storage.bucket),
 			Prefix:    aws.String(dir),
 			Delimiter: aws.String("/"),
-			MaxKeys:   aws.Int64(1000),
 		}
 
-		output, err := storage.client.ListObjects(&input)
+		err := storage.client.ListObjectsV2Pages(&input, func(page *s3.ListObjectsV2Output, lastPage bool) bool {
+			for _, subDir := range page.CommonPrefixes {
+				files = append(files, (*subDir.Prefix)[len(dir):])
+			}
+			return true
+		})
 		if err != nil {
 			return nil, nil, err
 		}
 
-		for _, subDir := range output.CommonPrefixes {
-			files = append(files, (*subDir.Prefix)[len(dir):])
-		}
 		return files, nil, nil
 	} else {
 		dir = storage.storageDir + dir
-		marker := ""
-		for {
-			input := s3.ListObjectsInput{
-				Bucket:  aws.String(storage.bucket),
-				Prefix:  aws.String(dir),
-				MaxKeys: aws.Int64(1000),
-				Marker:  aws.String(marker),
-			}
+		input := s3.ListObjectsV2Input{
+			Bucket:  aws.String(storage.bucket),
+			Prefix:  aws.String(dir),
+			MaxKeys: aws.Int64(1000),
+		}
 
-			output, err := storage.client.ListObjects(&input)
-			if err != nil {
-				return nil, nil, err
-			}
-
-			for _, object := range output.Contents {
+		err := storage.client.ListObjectsV2Pages(&input, func(page *s3.ListObjectsV2Output, lastPage bool) bool {
+			for _, object := range page.Contents {
 				files = append(files, (*object.Key)[len(dir):])
 				sizes = append(sizes, *object.Size)
 			}
-
-			if !*output.IsTruncated {
-				break
-			}
-
-			marker = *output.Contents[len(output.Contents)-1].Key
+			return true
+		})
+		if err != nil {
+			return nil, nil, err
 		}
 		return files, sizes, nil
 	}