s3: fix SetModTime on GLACIER/ARCHIVE objects and implement set/get tier

- Read the storage class for each object
- Implement SetTier/GetTier
- Check the storage class on the **object** before using SetModTime

This updates the fix in 1a2fb52 so that SetModTime works when you are
using objects which have been migrated to GLACIER but you aren't using
GLACIER as a storage class.

Fixes #3522

backend/s3/s3.go

@@ -818,6 +818,7 @@ type Object struct {
 	lastModified time.Time          // Last modified
 	meta         map[string]*string // The object metadata if known - may be nil
 	mimeType     string             // MimeType of object - may be ""
+	storageClass string             // eg GLACIER
 }
 
 // ------------------------------------------------------------
@@ -1089,6 +1090,8 @@ func NewFs(name, root string, m configmap.Mapper) (fs.Fs, error) {
 		WriteMimeType:     true,
 		BucketBased:       true,
 		BucketBasedRootOK: true,
+		SetTier:           true,
+		GetTier:           true,
 	}).Fill(f)
 	if f.rootBucket != "" && f.rootDirectory != "" {
 		// Check to see if the object exists
@@ -1132,6 +1135,7 @@ func (f *Fs) newObjectWithInfo(ctx context.Context, remote string, info *s3.Obje
 		}
 		o.etag = aws.StringValue(info.ETag)
 		o.bytes = aws.Int64Value(info.Size)
+		o.storageClass = aws.StringValue(info.StorageClass)
 	} else {
 		err := o.readMetaData(ctx) // reads info and meta, returning an error
 		if err != nil {
@@ -1550,6 +1554,31 @@ func pathEscape(s string) string {
 	return strings.Replace(rest.URLPathEscape(s), "+", "%2B", -1)
 }
 
+// copy does a server side copy
+//
+// It adds the boiler plate to the req passed in and calls the s3
+// method
+func (f *Fs) copy(ctx context.Context, req *s3.CopyObjectInput, dstBucket, dstPath, srcBucket, srcPath string) error {
+	req.Bucket = &dstBucket
+	req.ACL = &f.opt.ACL
+	req.Key = &dstPath
+	source := pathEscape(path.Join(srcBucket, srcPath))
+	req.CopySource = &source
+	if f.opt.ServerSideEncryption != "" {
+		req.ServerSideEncryption = &f.opt.ServerSideEncryption
+	}
+	if f.opt.SSEKMSKeyID != "" {
+		req.SSEKMSKeyId = &f.opt.SSEKMSKeyID
+	}
+	if req.StorageClass == nil && f.opt.StorageClass != "" {
+		req.StorageClass = &f.opt.StorageClass
+	}
+	return f.pacer.Call(func() (bool, error) {
+		_, err := f.c.CopyObjectWithContext(ctx, req)
+		return f.shouldRetry(err)
+	})
+}
+
 // Copy src to this remote using server side copy operations.
 //
 // This is stored with the remote path given
@@ -1571,27 +1600,10 @@ func (f *Fs) Copy(ctx context.Context, src fs.Object, remote string) (fs.Object,
 		return nil, fs.ErrorCantCopy
 	}
 	srcBucket, srcPath := srcObj.split()
-	source := pathEscape(path.Join(srcBucket, srcPath))
 	req := s3.CopyObjectInput{
-		Bucket:            &dstBucket,
-		ACL:               &f.opt.ACL,
-		Key:               &dstPath,
-		CopySource:        &source,
 		MetadataDirective: aws.String(s3.MetadataDirectiveCopy),
 	}
-	if f.opt.ServerSideEncryption != "" {
+	err = f.copy(ctx, &req, dstBucket, dstPath, srcBucket, srcPath)
-		req.ServerSideEncryption = &f.opt.ServerSideEncryption
-	}
-	if f.opt.SSEKMSKeyID != "" {
-		req.SSEKMSKeyId = &f.opt.SSEKMSKeyID
-	}
-	if f.opt.StorageClass != "" {
-		req.StorageClass = &f.opt.StorageClass
-	}
-	err = f.pacer.Call(func() (bool, error) {
-		_, err = f.c.CopyObjectWithContext(ctx, &req)
-		return f.shouldRetry(err)
-	})
 	if err != nil {
 		return nil, err
 	}
@@ -1691,6 +1703,7 @@ func (o *Object) readMetaData(ctx context.Context) (err error) {
 	o.etag = aws.StringValue(resp.ETag)
 	o.bytes = size
 	o.meta = resp.Metadata
+	o.storageClass = aws.StringValue(resp.StorageClass)
 	if resp.LastModified == nil {
 		fs.Logf(o, "Failed to read last modified from HEAD: %v", err)
 		o.lastModified = time.Now()
@@ -1741,39 +1754,19 @@ func (o *Object) SetModTime(ctx context.Context, modTime time.Time) error {
 		return nil
 	}
 
-	// Guess the content type
+	// Can't update metadata here, so return this error to force a recopy
-	mimeType := fs.MimeType(ctx, o)
+	if o.storageClass == "GLACIER" || o.storageClass == "DEEP_ARCHIVE" {
+		return fs.ErrorCantSetModTime
+	}
 
 	// Copy the object to itself to update the metadata
 	bucket, bucketPath := o.split()
-	sourceKey := path.Join(bucket, bucketPath)
-	directive := s3.MetadataDirectiveReplace // replace metadata with that passed in
 	req := s3.CopyObjectInput{
-		Bucket:            &bucket,
+		ContentType:       aws.String(fs.MimeType(ctx, o)), // Guess the content type
-		ACL:               &o.fs.opt.ACL,
-		Key:               &bucketPath,
-		ContentType:       &mimeType,
-		CopySource:        aws.String(pathEscape(sourceKey)),
 		Metadata:          o.meta,
-		MetadataDirective: &directive,
+		MetadataDirective: aws.String(s3.MetadataDirectiveReplace), // replace metadata with that passed in
 	}
-	if o.fs.opt.ServerSideEncryption != "" {
+	return o.fs.copy(ctx, &req, bucket, bucketPath, bucket, bucketPath)
-		req.ServerSideEncryption = &o.fs.opt.ServerSideEncryption
-	}
-	if o.fs.opt.SSEKMSKeyID != "" {
-		req.SSEKMSKeyId = &o.fs.opt.SSEKMSKeyID
-	}
-	if o.fs.opt.StorageClass == "GLACIER" || o.fs.opt.StorageClass == "DEEP_ARCHIVE" {
-		return fs.ErrorCantSetModTime
-	}
-	if o.fs.opt.StorageClass != "" {
-		req.StorageClass = &o.fs.opt.StorageClass
-	}
-	err = o.fs.pacer.Call(func() (bool, error) {
-		_, err := o.fs.c.CopyObjectWithContext(ctx, &req)
-		return o.fs.shouldRetry(err)
-	})
-	return err
 }
 
 // Storable raturns a boolean indicating if this object is storable
@@ -1998,6 +1991,31 @@ func (o *Object) MimeType(ctx context.Context) string {
 	return o.mimeType
 }
 
+// SetTier performs changing storage class
+func (o *Object) SetTier(tier string) (err error) {
+	ctx := context.TODO()
+	tier = strings.ToUpper(tier)
+	bucket, bucketPath := o.split()
+	req := s3.CopyObjectInput{
+		MetadataDirective: aws.String(s3.MetadataDirectiveCopy),
+		StorageClass:      aws.String(tier),
+	}
+	err = o.fs.copy(ctx, &req, bucket, bucketPath, bucket, bucketPath)
+	if err != nil {
+		return err
+	}
+	o.storageClass = tier
+	return err
+}
+
+// GetTier returns storage class as string
+func (o *Object) GetTier() string {
+	if o.storageClass == "" {
+		return "STANDARD"
+	}
+	return o.storageClass
+}
+
 // Check the interfaces are satisfied
 var (
 	_ fs.Fs          = &Fs{}
@@ -2006,4 +2024,6 @@ var (
 	_ fs.ListRer     = &Fs{}
 	_ fs.Object      = &Object{}
 	_ fs.MimeTyper   = &Object{}
+	_ fs.GetTierer   = &Object{}
+	_ fs.SetTierer   = &Object{}
 )

backend/s3/s3_test.go

@@ -13,6 +13,7 @@ func TestIntegration(t *testing.T) {
 	fstests.Run(t, &fstests.Opt{
 		RemoteName:  "TestS3:",
 		NilObject:   (*Object)(nil),
+		TiersToTest: []string{"STANDARD", "STANDARD_IA"},
 		ChunkedUpload: fstests.ChunkedUploadConfig{
 			MinChunkSize: minChunkSize,
 		},