feat: add gsc and go_storage package

storage.go

@@ -0,0 +1,140 @@
+package go_storage
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"strings"
+	"time"
+)
+
+// Storage defines the interface for remote file storage operations.
+// All implementations must be safe for concurrent use.
+type Storage interface {
+	// Upload uploads a local file to the remote storage with the given target name.
+	Upload(ctx context.Context, localPath string, remotePath string) error
+
+	// Download downloads a file from remote storage to a local path.
+	Download(ctx context.Context, remotePath string, localPath string) error
+
+	// List returns all items in the storage that match the given prefix.
+	List(ctx context.Context, prefix string) ([]Item, error)
+
+	// Remove deletes a file from remote storage.
+	Remove(ctx context.Context, remotePath string) error
+
+	// Close releases any resources held by the storage implementation.
+	Close() error
+}
+
+// Item represents a file or directory in remote storage.
+type Item struct {
+	Key          string    // The path/key of the item
+	ModifiedTime time.Time // Last modification time
+	Size         int64     // Size in bytes (0 for directories)
+	IsDirectory  bool      // Whether this item is a directory
+}
+
+// Config holds configuration options for creating storage instances.
+type Config struct {
+	// S3 configuration
+	S3Region     string
+	S3Bucket     string
+	S3Profile    string
+	S3KeyID      string
+	S3Secret     string
+	S3Endpoint   string
+	S3ForcePath  bool
+	S3DisableTLS bool
+
+	// B2 configuration
+	B2KeyID                 string
+	B2AppKey                string
+	B2Bucket                string
+	B2ConcurrentConnections int
+	B2ForcePath             bool
+
+	// Google Cloud Storage configuration
+	GCSBucket          string
+	GCSEndpoint        string
+	GCSCredentialsFile string
+
+	// Azure configuration
+	AzureAccount   string
+	AzureKey       string
+	AzureContainer string
+	AzureEndpoint  string
+
+	// SFTP configuration
+	SFTPHost             string
+	SFTPPort             string
+	SFTPUsername         string
+	SFTPPassword         string
+	SFTPDirectory        string
+	SFTPIdentityFile     string
+	SFTPIgnoreKnownHosts bool
+
+	// FTP configuration
+	FTPHost      string
+	FTPPort      string
+	FTPUsername  string
+	FTPPassword  string
+	FTPDirectory string
+}
+
+// StorageType represents the type of storage backend.
+type StorageType string
+
+const (
+	StorageTypeS3    StorageType = "s3"
+	StorageTypeGCS   StorageType = "gcs"
+	StorageTypeAzure StorageType = "azure"
+	StorageTypeSFTP  StorageType = "sftp"
+	StorageTypeFTP   StorageType = "ftp"
+	StorageTypeLocal StorageType = "local"
+)
+
+// NewStorage creates a new Storage instance based on the specified type and configuration.
+func NewStorage(storageType StorageType, config Config) (Storage, error) {
+	switch storageType {
+	case StorageTypeS3:
+		return NewS3Storage(config)
+	case StorageTypeGCS:
+		return NewGCSStorage(config)
+	case StorageTypeAzure:
+		return NewAzureStorage(config)
+	case StorageTypeSFTP:
+		return NewSFTPStorage(config)
+	case StorageTypeFTP:
+		return NewFTPStorage(config)
+	case StorageTypeLocal:
+		return NewLocalStorage("/backups")
+	default:
+		return nil, fmt.Errorf("unsupported storage type: %s", storageType)
+	}
+}
+
+// normalizePathSeparators converts OS-specific path separators to forward slashes.
+// This is necessary for cloud storage services which expect forward slashes.
+func normalizePathSeparators(path string) string {
+	if os.PathSeparator == '/' {
+		return path
+	}
+	return strings.ReplaceAll(path, string(os.PathSeparator), "/")
+}
+
+// validateConfig checks if the required configuration fields are present.
+func validateConfig(_ Config, requiredFields map[string]string) error {
+	var missing []string
+	for field, value := range requiredFields {
+		if value == "" {
+			missing = append(missing, field)
+		}
+	}
+
+	if len(missing) > 0 {
+		return fmt.Errorf("missing required configuration: %s", strings.Join(missing, ", "))
+	}
+
+	return nil
+}