feat(s3): Add support for S3 object storage classes

Introduces a new 'storage_class' configuration option for S3 providers. Users can now specify the desired storage class (e.g., Standard, GLACIER, DEEP_ARCHIVE) for objects uploaded to S3-compatible services like AWS S3 and Tencent COS.

The input storage class string is normalized to match AWS SDK constants, supporting various common aliases. If an unknown storage class is provided, it will be used as a raw value with a warning. This enhancement provides greater control over storage costs and data access patterns.

drivers/s3/driver.go

@@ -15,6 +15,7 @@ import (
 	"github.com/alist-org/alist/v3/internal/stream"
 	"github.com/alist-org/alist/v3/pkg/cron"
 	"github.com/alist-org/alist/v3/server/common"
+	"github.com/aws/aws-sdk-go/aws"
 	"github.com/aws/aws-sdk-go/aws/session"
 	"github.com/aws/aws-sdk-go/service/s3"
 	"github.com/aws/aws-sdk-go/service/s3/s3manager"
@@ -32,6 +33,33 @@ type S3 struct {
 	cron   *cron.Cron
 }
 
+var storageClassLookup = map[string]string{
+	"standard":            s3.ObjectStorageClassStandard,
+	"reduced_redundancy":  s3.ObjectStorageClassReducedRedundancy,
+	"glacier":             s3.ObjectStorageClassGlacier,
+	"standard_ia":         s3.ObjectStorageClassStandardIa,
+	"onezone_ia":          s3.ObjectStorageClassOnezoneIa,
+	"intelligent_tiering": s3.ObjectStorageClassIntelligentTiering,
+	"deep_archive":        s3.ObjectStorageClassDeepArchive,
+	"outposts":            s3.ObjectStorageClassOutposts,
+	"glacier_ir":          s3.ObjectStorageClassGlacierIr,
+	"snow":                s3.ObjectStorageClassSnow,
+	"express_onezone":     s3.ObjectStorageClassExpressOnezone,
+}
+
+func (d *S3) resolveStorageClass() *string {
+	value := strings.TrimSpace(d.StorageClass)
+	if value == "" {
+		return nil
+	}
+	normalized := strings.ToLower(strings.ReplaceAll(value, "-", "_"))
+	if v, ok := storageClassLookup[normalized]; ok {
+		return aws.String(v)
+	}
+	log.Warnf("s3: unknown storage class %q, using raw value", d.StorageClass)
+	return aws.String(value)
+}
+
 func (d *S3) Config() driver.Config {
 	return d.config
 }
@@ -179,6 +207,9 @@ func (d *S3) Put(ctx context.Context, dstDir model.Obj, s model.FileStreamer, up
 		}),
 		ContentType: &contentType,
 	}
+	if storageClass := d.resolveStorageClass(); storageClass != nil {
+		input.StorageClass = storageClass
+	}
 	_, err := uploader.UploadWithContext(ctx, input)
 	return err
 }

drivers/s3/meta.go

@@ -21,6 +21,7 @@ type Addition struct {
 	ListObjectVersion        string `json:"list_object_version" type:"select" options:"v1,v2" default:"v1"`
 	RemoveBucket             bool   `json:"remove_bucket" help:"Remove bucket name from path when using custom host."`
 	AddFilenameToDisposition bool   `json:"add_filename_to_disposition" help:"Add filename to Content-Disposition header."`
+	StorageClass             string `json:"storage_class" type:"select" options:",standard,standard_ia,onezone_ia,intelligent_tiering,glacier,glacier_ir,deep_archive,archive" help:"Storage class for new objects. AWS and Tencent COS support different subsets (COS uses ARCHIVE/DEEP_ARCHIVE)."`
 }
 
 func init() {

drivers/s3/util.go

@@ -202,6 +202,9 @@ func (d *S3) copyFile(ctx context.Context, src string, dst string) error {
 		CopySource: aws.String(url.PathEscape(d.Bucket + "/" + srcKey)),
 		Key:        &dstKey,
 	}
+	if storageClass := d.resolveStorageClass(); storageClass != nil {
+		input.StorageClass = storageClass
+	}
 	_, err := d.client.CopyObject(input)
 	return err
 }