feat: add gsc and go_storage package

gcs.go

@@ -0,0 +1,156 @@
+package go_storage
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"os"
+
+	"cloud.google.com/go/storage"
+	"google.golang.org/api/iterator"
+	"google.golang.org/api/option"
+)
+
+// GCSStorage implements Storage interface for Google Cloud Storage.
+type GCSStorage struct {
+	client *storage.Client
+	bucket string
+}
+
+// NewGCSStorage creates a new Google Cloud Storage instance.
+func NewGCSStorage(config Config) (*GCSStorage, error) {
+	if err := validateConfig(config, map[string]string{
+		"bucket": config.GCSBucket,
+	}); err != nil {
+		return nil, fmt.Errorf("gcs: %w", err)
+	}
+
+	options := make([]option.ClientOption, 0)
+
+	if config.GCSEndpoint != "" {
+		options = append(options, option.WithEndpoint(config.GCSEndpoint))
+	}
+
+	if config.GCSCredentialsFile != "" {
+		options = append(options, option.WithCredentialsFile(config.GCSCredentialsFile))
+	}
+
+	client, err := storage.NewClient(context.Background(), options...)
+	if err != nil {
+		return nil, fmt.Errorf("gcs: failed to create client: %w", err)
+	}
+
+	return &GCSStorage{
+		client: client,
+		bucket: config.GCSBucket,
+	}, nil
+}
+
+// Upload uploads a file to GCS.
+func (g *GCSStorage) Upload(ctx context.Context, localPath string, remotePath string) error {
+	file, err := os.Open(localPath)
+	if err != nil {
+		return fmt.Errorf("gcs: failed to open local file: %w", err)
+	}
+	defer func(file *os.File) {
+		err = file.Close()
+		if err != nil {
+			fmt.Printf("gcs: failed to close file: %v\n", err)
+		}
+	}(file)
+
+	obj := g.client.Bucket(g.bucket).Object(normalizePathSeparators(remotePath)).NewWriter(ctx)
+	defer func(obj *storage.Writer) {
+		err = obj.Close()
+		if err != nil {
+			fmt.Printf("gcs: failed to close object writer: %v\n", err)
+		}
+	}(obj)
+
+	if _, err := io.Copy(obj, file); err != nil {
+		return fmt.Errorf("gcs: failed to write data: %w", err)
+	}
+
+	if err = obj.Close(); err != nil {
+		return fmt.Errorf("gcs: failed to finalize upload: %w", err)
+	}
+
+	return nil
+}
+
+// Download downloads a file from GCS.
+func (g *GCSStorage) Download(ctx context.Context, remotePath string, localPath string) error {
+	file, err := os.Create(localPath)
+	if err != nil {
+		return fmt.Errorf("gcs: failed to create local file: %w", err)
+	}
+	defer func(file *os.File) {
+		err = file.Close()
+		if err != nil {
+			fmt.Printf("gcs: failed to close file: %v\n", err)
+		}
+	}(file)
+
+	obj, err := g.client.Bucket(g.bucket).Object(normalizePathSeparators(remotePath)).NewReader(ctx)
+	if err != nil {
+		return fmt.Errorf("gcs: failed to create reader: %w", err)
+	}
+	defer func(obj *storage.Reader) {
+		err = obj.Close()
+		if err != nil {
+			fmt.Printf("gcs: failed to close object reader: %v\n", err)
+		}
+	}(obj)
+
+	if _, err = io.Copy(file, obj); err != nil {
+		return fmt.Errorf("gcs: failed to read data: %w", err)
+	}
+
+	return nil
+}
+
+// List lists objects in GCS with the given prefix.
+func (g *GCSStorage) List(ctx context.Context, prefix string) ([]Item, error) {
+	items := make([]Item, 0)
+
+	query := &storage.Query{
+		Prefix: normalizePathSeparators(prefix),
+	}
+
+	it := g.client.Bucket(g.bucket).Objects(ctx, query)
+
+	for {
+		attrs, err := it.Next()
+		if err == iterator.Done {
+			break
+		}
+		if err != nil {
+			return nil, fmt.Errorf("gcs: failed to iterate objects: %w", err)
+		}
+
+		items = append(items, Item{
+			Key:          attrs.Name,
+			ModifiedTime: attrs.Updated,
+			Size:         attrs.Size,
+			IsDirectory:  false,
+		})
+	}
+
+	return items, nil
+}
+
+// Remove deletes an object from GCS.
+func (g *GCSStorage) Remove(ctx context.Context, remotePath string) error {
+	obj := g.client.Bucket(g.bucket).Object(normalizePathSeparators(remotePath))
+
+	if err := obj.Delete(ctx); err != nil {
+		return fmt.Errorf("gcs: failed to remove object from bucket %s: %w", g.bucket, err)
+	}
+
+	return nil
+}
+
+// Close releases resources.
+func (g *GCSStorage) Close() error {
+	return g.client.Close()
+}