fix: move RFC 3339 time formatting to s3response

It is better if we let the s3response module handle the xml
formatting spec specifics, and let the backends not worry
about how to format the time fields. This should help to
prevent any future backend modifications or additions from
accidental incorrect time formatting.

backend/azure/azure.go

@@ -559,7 +559,7 @@ Pager:
 			objects = append(objects, s3response.Object{
 				ETag:         (*string)(v.Properties.ETag),
 				Key:          v.Name,
-				LastModified: backend.GetStringPtr(v.Properties.LastModified.UTC().Format(backend.RFC3339TimeFormat)),
+				LastModified: v.Properties.LastModified,
 				Size:         v.Properties.ContentLength,
 				StorageClass: types.ObjectStorageClass(*v.Properties.AccessTier),
 			})
@@ -620,7 +620,7 @@ Pager:
 			objects = append(objects, s3response.Object{
 				ETag:         (*string)(v.Properties.ETag),
 				Key:          v.Name,
-				LastModified: backend.GetStringPtr(v.Properties.LastModified.UTC().Format(backend.RFC3339TimeFormat)),
+				LastModified: v.Properties.LastModified,
 				Size:         v.Properties.ContentLength,
 				StorageClass: types.ObjectStorageClass(*v.Properties.AccessTier),
 			})
@@ -868,7 +868,7 @@ func (az *Azure) ListParts(ctx context.Context, input *s3.ListPartsInput) (s3res
 			Size:         *el.Size,
 			ETag:         *el.Name,
 			PartNumber:   partNumber,
-			LastModified: time.Now().Format(backend.RFC3339TimeFormat),
+			LastModified: time.Now(),
 		})
 		if len(parts) >= int(maxParts) {
 			nextPartNumberMarker = partNumber
@@ -923,7 +923,7 @@ func (az *Azure) ListMultipartUploads(ctx context.Context, input *s3.ListMultipa
 				}
 				uploads = append(uploads, s3response.Upload{
 					Key:       *el.Name,
-					Initiated: el.Properties.CreationTime.Format(backend.RFC3339TimeFormat),
+					Initiated: *el.Properties.CreationTime,
 				})
 			}
 		}

backend/common.go

@@ -30,11 +30,6 @@ import (
 	"github.com/versity/versitygw/s3response"
 )
 
-var (
-	// RFC3339TimeFormat RFC3339 time format
-	RFC3339TimeFormat = "2006-01-02T15:04:05.999Z"
-)
-
 func IsValidBucketName(name string) bool { return true }
 
 type ByBucketName []s3response.ListAllMyBucketsEntry

backend/posix/posix.go

@@ -943,7 +943,7 @@ func (p *Posix) ListMultipartUploads(_ context.Context, mpu *s3.ListMultipartUpl
 			uploads = append(uploads, s3response.Upload{
 				Key:       objectName,
 				UploadID:  uploadID,
-				Initiated: fi.ModTime().Format(backend.RFC3339TimeFormat),
+				Initiated: fi.ModTime(),
 			})
 		}
 	}
@@ -1088,7 +1088,7 @@ func (p *Posix) ListParts(_ context.Context, input *s3.ListPartsInput) (s3respon
 		parts = append(parts, s3response.Part{
 			PartNumber:   pn,
 			ETag:         etag,
-			LastModified: fi.ModTime().Format(backend.RFC3339TimeFormat),
+			LastModified: fi.ModTime(),
 			Size:         fi.Size(),
 		})
 	}
@@ -2155,12 +2155,12 @@ func (p *Posix) fileToObj(bucket string) backend.GetObjFunc {
 			}
 
 			size := int64(0)
-			mDate := fi.ModTime().UTC().Format(backend.RFC3339TimeFormat)
+			mtime := fi.ModTime()
 
 			return s3response.Object{
 				ETag:         &etag,
 				Key:          &path,
-				LastModified: &mDate,
+				LastModified: &mtime,
 				Size:         &size,
 			}, nil
 		}
@@ -2187,12 +2187,12 @@ func (p *Posix) fileToObj(bucket string) backend.GetObjFunc {
 		}
 
 		size := fi.Size()
-		mDate := fi.ModTime().UTC().Format(backend.RFC3339TimeFormat)
+		mtime := fi.ModTime()
 
 		return s3response.Object{
 			ETag:         &etag,
 			Key:          &path,
-			LastModified: &mDate,
+			LastModified: &mtime,
 			Size:         &size,
 		}, nil
 	}

backend/s3proxy/s3.go

@@ -204,7 +204,7 @@ func (s *S3Proxy) ListMultipartUploads(ctx context.Context, input *s3.ListMultip
 				DisplayName: *u.Owner.DisplayName,
 			},
 			StorageClass: string(u.StorageClass),
-			Initiated:    u.Initiated.Format(backend.RFC3339TimeFormat),
+			Initiated:    *u.Initiated,
 		})
 	}
 
@@ -241,7 +241,7 @@ func (s *S3Proxy) ListParts(ctx context.Context, input *s3.ListPartsInput) (s3re
 	for _, p := range output.Parts {
 		parts = append(parts, s3response.Part{
 			PartNumber:   int(*p.PartNumber),
-			LastModified: p.LastModified.Format(backend.RFC3339TimeFormat),
+			LastModified: *p.LastModified,
 			ETag:         *p.ETag,
 			Size:         *p.Size,
 		})
@@ -776,11 +776,10 @@ func convertObjects(objs []types.Object) []s3response.Object {
 	result := make([]s3response.Object, len(objs))
 
 	for _, obj := range objs {
-		lastModified := obj.LastModified.UTC().Format(backend.RFC3339TimeFormat)
 		result = append(result, s3response.Object{
 			ETag:          obj.ETag,
 			Key:           obj.Key,
-			LastModified:  &lastModified,
+			LastModified:  obj.LastModified,
 			Owner:         obj.Owner,
 			Size:          obj.Size,
 			RestoreStatus: obj.RestoreStatus,

backend/scoutfs/scoutfs.go

@@ -858,11 +858,12 @@ func (s *ScoutFS) fileToObj(bucket string) backend.GetObjFunc {
 			}
 
 			key := path + "/"
+			mtime := fi.ModTime()
 
 			return s3response.Object{
 				ETag:         &etag,
 				Key:          &key,
-				LastModified: backend.GetStringPtr(fi.ModTime().UTC().Format(backend.RFC3339TimeFormat)),
+				LastModified: &mtime,
 				StorageClass: types.ObjectStorageClassStandard,
 			}, nil
 		}
@@ -905,11 +906,12 @@ func (s *ScoutFS) fileToObj(bucket string) backend.GetObjFunc {
 		}
 
 		size := fi.Size()
+		mtime := fi.ModTime()
 
 		return s3response.Object{
 			ETag:         &etag,
 			Key:          &path,
-			LastModified: backend.GetStringPtr(fi.ModTime().UTC().Format(backend.RFC3339TimeFormat)),
+			LastModified: &mtime,
 			Size:         &size,
 			StorageClass: sc,
 		}, nil

backend/walk_test.go

@@ -44,11 +44,12 @@ func getObj(path string, d fs.DirEntry) (s3response.Object, error) {
 		if err != nil {
 			return s3response.Object{}, fmt.Errorf("get fileinfo: %w", err)
 		}
+		mtime := fi.ModTime()
 
 		return s3response.Object{
 			ETag:         &etag,
 			Key:          &path,
-			LastModified: backend.GetStringPtr(fi.ModTime().UTC().Format(backend.RFC3339TimeFormat)),
+			LastModified: &mtime,
 		}, nil
 	}
 
@@ -60,11 +61,12 @@ func getObj(path string, d fs.DirEntry) (s3response.Object, error) {
 	}
 
 	size := fi.Size()
+	mtime := fi.ModTime()
 
 	return s3response.Object{
 		ETag:         &etag,
 		Key:          &path,
-		LastModified: backend.GetStringPtr(fi.ModTime().UTC().Format(backend.RFC3339TimeFormat)),
+		LastModified: &mtime,
 		Size:         &size,
 	}, nil
 }

s3response/s3response.go

@@ -21,14 +21,30 @@ import (
 	"github.com/aws/aws-sdk-go-v2/service/s3/types"
 )
 
+const RFC3339TimeFormat = "2006-01-02T15:04:05.999Z"
+
 // Part describes part metadata.
 type Part struct {
 	PartNumber   int
-	LastModified string
+	LastModified time.Time
 	ETag         string
 	Size         int64
 }
 
+func (p Part) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
+	type Alias Part
+	aux := &struct {
+		LastModified string `xml:"LastModified"`
+		*Alias
+	}{
+		Alias: (*Alias)(&p),
+	}
+
+	aux.LastModified = p.LastModified.Format(RFC3339TimeFormat)
+
+	return e.EncodeElement(aux, start)
+}
+
 // ListPartsResponse - s3 api list parts response.
 type ListPartsResult struct {
 	XMLName xml.Name `xml:"http://s3.amazonaws.com/doc/2006-03-01/ ListPartsResult" json:"-"`
@@ -124,21 +140,52 @@ type ListObjectsV2Result struct {
 type Object struct {
 	ETag          *string
 	Key           *string
-	LastModified  *string
+	LastModified  *time.Time
 	Owner         *types.Owner
 	RestoreStatus *types.RestoreStatus
 	Size          *int64
 	StorageClass  types.ObjectStorageClass
 }
 
+func (o Object) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
+	type Alias Object
+	aux := &struct {
+		LastModified *string `xml:"LastModified,omitempty"`
+		*Alias
+	}{
+		Alias: (*Alias)(&o),
+	}
+
+	if o.LastModified != nil {
+		formattedTime := o.LastModified.Format(RFC3339TimeFormat)
+		aux.LastModified = &formattedTime
+	}
+
+	return e.EncodeElement(aux, start)
+}
+
 // Upload describes in progress multipart upload
 type Upload struct {
 	Key          string
 	UploadID     string `xml:"UploadId"`
 	Initiator    Initiator
 	Owner        Owner
 	StorageClass string
-	Initiated    string
+	Initiated    time.Time
+}
+
+func (u Upload) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
+	type Alias Upload
+	aux := &struct {
+		Initiated string `xml:"Initiated"`
+		*Alias
+	}{
+		Alias: (*Alias)(&u),
+	}
+
+	aux.Initiated = u.Initiated.Format(RFC3339TimeFormat)
+
+	return e.EncodeElement(aux, start)
 }
 
 // CommonPrefix ListObjectsResponse common prefixes (directory abstraction)