s3api: implement GetObjectAttributes handler

Add GetObjectAttributesHandler that returns selected object metadata (ETag, Checksum, StorageClass, ObjectSize, ObjectParts) without returning the object body. Follows the same versioning and conditional header patterns as HeadObjectHandler. The handler parses the X-Amz-Object-Attributes header to determine which attributes to include in the XML response, and supports ObjectParts pagination via X-Amz-Max-Parts and X-Amz-Part-Number-Marker. Ref: https://docs.aws.amazon.com/AmazonS3/latest/API/API_GetObjectAttributes.html Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
3 days ago · a38ae284bf
1 changed files with 307 additions and 0 deletions
--- a/weed/s3api/s3api_object_handlers_attributes.go
+++ b/weed/s3api/s3api_object_handlers_attributes.go
@ -0,0 +1,307 @@
+package s3api
+
+import (
+	"encoding/json"
+	"encoding/xml"
+	"errors"
+	"net/http"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/seaweedfs/seaweedfs/weed/glog"
+	"github.com/seaweedfs/seaweedfs/weed/pb/filer_pb"
+	"github.com/seaweedfs/seaweedfs/weed/s3api/s3_constants"
+	"github.com/seaweedfs/seaweedfs/weed/s3api/s3err"
+)
+
+const maxPartsListDefault = 1000
+
+// GetObjectAttributesResponse is the XML response for GetObjectAttributes.
+type GetObjectAttributesResponse struct {
+	XMLName      xml.Name                  `xml:"GetObjectAttributesResponse"`
+	ETag         string                    `xml:"ETag,omitempty"`
+	Checksum     *ObjectAttributesChecksum `xml:"Checksum,omitempty"`
+	ObjectParts  *ObjectAttributesParts    `xml:"ObjectParts,omitempty"`
+	StorageClass string                    `xml:"StorageClass,omitempty"`
+	ObjectSize   *int64                    `xml:"ObjectSize,omitempty"`
+}
+
+// ObjectAttributesChecksum holds checksum info for GetObjectAttributes.
+type ObjectAttributesChecksum struct {
+	ChecksumCRC32  string `xml:"ChecksumCRC32,omitempty"`
+	ChecksumCRC32C string `xml:"ChecksumCRC32C,omitempty"`
+	ChecksumSHA1   string `xml:"ChecksumSHA1,omitempty"`
+	ChecksumSHA256 string `xml:"ChecksumSHA256,omitempty"`
+}
+
+// ObjectAttributesParts holds parts info for GetObjectAttributes.
+type ObjectAttributesParts struct {
+	IsTruncated          bool                    `xml:"IsTruncated"`
+	MaxParts             int                     `xml:"MaxParts"`
+	NextPartNumberMarker int                     `xml:"NextPartNumberMarker"`
+	PartNumberMarker     int                     `xml:"PartNumberMarker"`
+	PartsCount           int                     `xml:"PartsCount"`
+	Parts                []*ObjectAttributesPart `xml:"Part"`
+}
+
+// ObjectAttributesPart holds info for a single part.
+type ObjectAttributesPart struct {
+	PartNumber int   `xml:"PartNumber"`
+	Size       int64 `xml:"Size"`
+}
+
+// parseObjectAttributes parses the X-Amz-Object-Attributes header.
+func parseObjectAttributes(h http.Header) map[string]struct{} {
+	attrs := make(map[string]struct{})
+	for _, headerVal := range h.Values(s3_constants.AmzObjectAttributes) {
+		for _, v := range strings.Split(strings.TrimSpace(headerVal), ",") {
+			v = strings.TrimSpace(v)
+			if v != "" {
+				attrs[v] = struct{}{}
+			}
+		}
+	}
+	return attrs
+}
+
+// validateObjectAttributes checks that all requested attributes are valid.
+func validateObjectAttributes(attrs map[string]struct{}) bool {
+	for attr := range attrs {
+		switch attr {
+		case "ETag", "Checksum", "StorageClass", "ObjectSize", "ObjectParts":
+		default:
+			return false
+		}
+	}
+	return true
+}
+
+func (s3a *S3ApiServer) GetObjectAttributesHandler(w http.ResponseWriter, r *http.Request) {
+	bucket, object := s3_constants.GetBucketAndObject(r)
+	glog.V(3).Infof("GetObjectAttributesHandler %s %s", bucket, object)
+
+	// Parse and validate requested attributes
+	requestedAttrs := parseObjectAttributes(r.Header)
+	if len(requestedAttrs) == 0 || !validateObjectAttributes(requestedAttrs) {
+		s3err.WriteErrorResponse(w, r, s3err.ErrInvalidAttributeName)
+		return
+	}
+
+	// Parse optional pagination headers for ObjectParts
+	maxParts := maxPartsListDefault
+	if v := r.Header.Get(s3_constants.AmzMaxParts); v != "" {
+		if parsed, err := strconv.Atoi(v); err == nil && parsed >= 0 {
+			maxParts = parsed
+			if maxParts > maxPartsListDefault {
+				maxParts = maxPartsListDefault
+			}
+		}
+	}
+	partNumberMarker := 0
+	if v := r.Header.Get(s3_constants.AmzPartNumberMarker); v != "" {
+		if parsed, err := strconv.Atoi(v); err == nil && parsed >= 0 {
+			partNumberMarker = parsed
+		}
+	}
+
+	// Process conditional headers
+	result, handled := s3a.processConditionalHeaders(w, r, bucket, object, "GetObjectAttributesHandler")
+	if handled {
+		return
+	}
+
+	// Check for specific version ID
+	versionId := r.URL.Query().Get("versionId")
+
+	var (
+		entry *filer_pb.Entry
+		err   error
+	)
+
+	versioningConfigured, err := s3a.isVersioningConfigured(bucket)
+	if err != nil {
+		if err == filer_pb.ErrNotFound {
+			s3err.WriteErrorResponse(w, r, s3err.ErrNoSuchBucket)
+			return
+		}
+		glog.Errorf("Error checking versioning for bucket %s: %v", bucket, err)
+		s3err.WriteErrorResponse(w, r, s3err.ErrInternalError)
+		return
+	}
+
+	if versioningConfigured {
+		var targetVersionId string
+
+		if versionId != "" {
+			entry, err = s3a.getSpecificObjectVersion(bucket, object, versionId)
+			if err != nil {
+				s3err.WriteErrorResponse(w, r, s3err.ErrNoSuchKey)
+				return
+			}
+			targetVersionId = versionId
+		} else {
+			bucketDir := s3a.bucketDir(bucket)
+			normalizedObject := s3_constants.NormalizeObjectKey(object)
+			versionsDir := normalizedObject + s3_constants.VersionsFolder
+
+			versionsEntry, versionsErr := s3a.getEntry(bucketDir, versionsDir)
+			if versionsErr == nil && versionsEntry != nil {
+				entry, err = s3a.getLatestObjectVersion(bucket, object)
+				if err != nil {
+					s3err.WriteErrorResponse(w, r, s3err.ErrNoSuchKey)
+					return
+				}
+			} else if errors.Is(versionsErr, filer_pb.ErrNotFound) {
+				regularEntry, regularErr := s3a.getEntry(bucketDir, normalizedObject)
+				if regularErr == nil && regularEntry != nil {
+					entry = regularEntry
+					targetVersionId = "null"
+				} else {
+					s3err.WriteErrorResponse(w, r, s3err.ErrNoSuchKey)
+					return
+				}
+			} else {
+				entry, err = s3a.getLatestObjectVersion(bucket, object)
+				if err != nil {
+					s3err.WriteErrorResponse(w, r, s3err.ErrNoSuchKey)
+					return
+				}
+			}
+
+			if targetVersionId == "" {
+				if entry.Extended != nil {
+					if versionIdBytes, exists := entry.Extended[s3_constants.ExtVersionIdKey]; exists {
+						targetVersionId = string(versionIdBytes)
+					}
+				}
+				if targetVersionId == "" {
+					targetVersionId = "null"
+				}
+			}
+		}
+
+		// Check for delete marker
+		if entry.Extended != nil {
+			if deleteMarker, exists := entry.Extended[s3_constants.ExtDeleteMarkerKey]; exists && string(deleteMarker) == "true" {
+				w.Header().Set(s3_constants.AmzDeleteMarker, "true")
+				s3err.WriteErrorResponse(w, r, s3err.ErrNoSuchKey)
+				return
+			}
+		}
+
+		w.Header().Set("x-amz-version-id", targetVersionId)
+	} else {
+		// Non-versioned: reuse entry from conditional check or fetch
+		if result.Entry != nil {
+			entry = result.Entry
+		} else {
+			entry, err = s3a.fetchObjectEntry(bucket, object)
+			if err != nil {
+				s3err.WriteErrorResponse(w, r, s3err.ErrInternalError)
+				return
+			}
+			if entry == nil {
+				s3err.WriteErrorResponse(w, r, s3err.ErrNoSuchKey)
+				return
+			}
+		}
+	}
+
+	if entry == nil {
+		s3err.WriteErrorResponse(w, r, s3err.ErrInternalError)
+		return
+	}
+
+	// Build response with only requested attributes
+	resp := &GetObjectAttributesResponse{}
+
+	if _, ok := requestedAttrs["ETag"]; ok {
+		etag := s3a.getObjectETag(entry)
+		resp.ETag = strings.Trim(etag, `"`)
+	}
+
+	if _, ok := requestedAttrs["StorageClass"]; ok {
+		storageClass := "STANDARD"
+		if entry.Extended != nil {
+			if sc, exists := entry.Extended[s3_constants.AmzStorageClass]; exists && len(sc) > 0 {
+				storageClass = string(sc)
+			}
+		}
+		resp.StorageClass = storageClass
+	}
+
+	if _, ok := requestedAttrs["ObjectSize"]; ok {
+		var size int64
+		if entry.Attributes != nil {
+			size = int64(entry.Attributes.FileSize)
+		}
+		resp.ObjectSize = &size
+	}
+
+	if _, ok := requestedAttrs["ObjectParts"]; ok {
+		resp.ObjectParts = s3a.buildObjectAttributesParts(entry, maxParts, partNumberMarker)
+	}
+
+	// Set Last-Modified, remove Content-Type
+	if entry.Attributes != nil && entry.Attributes.Mtime > 0 {
+		w.Header().Set("Last-Modified", time.Unix(entry.Attributes.Mtime, 0).UTC().Format(http.TimeFormat))
+	}
+	w.Header().Del("Content-Type")
+
+	writeSuccessResponseXML(w, r, resp)
+}
+
+// buildObjectAttributesParts builds the ObjectParts section from multipart metadata.
+func (s3a *S3ApiServer) buildObjectAttributesParts(entry *filer_pb.Entry, maxParts, partNumberMarker int) *ObjectAttributesParts {
+	if entry.Extended == nil {
+		return nil
+	}
+
+	boundariesJSON, exists := entry.Extended[s3_constants.SeaweedFSMultipartPartBoundaries]
+	if !exists {
+		return nil
+	}
+
+	var boundaries []PartBoundaryInfo
+	if err := json.Unmarshal(boundariesJSON, &boundaries); err != nil {
+		glog.Warningf("GetObjectAttributes: failed to unmarshal part boundaries: %v", err)
+		return nil
+	}
+
+	if len(boundaries) == 0 {
+		return nil
+	}
+
+	parts := &ObjectAttributesParts{
+		PartNumberMarker: partNumberMarker,
+		MaxParts:         maxParts,
+		PartsCount:       len(boundaries),
+	}
+
+	chunks := entry.GetChunks()
+	for _, b := range boundaries {
+		if b.PartNumber <= partNumberMarker {
+			continue
+		}
+		if len(parts.Parts) >= maxParts {
+			parts.IsTruncated = true
+			break
+		}
+
+		var partSize int64
+		if b.StartChunk < len(chunks) && b.EndChunk <= len(chunks) && b.StartChunk < b.EndChunk {
+			for ci := b.StartChunk; ci < b.EndChunk; ci++ {
+				partSize += int64(chunks[ci].Size)
+			}
+		}
+
+		parts.NextPartNumberMarker = b.PartNumber
+		parts.Parts = append(parts.Parts, &ObjectAttributesPart{
+			PartNumber: b.PartNumber,
+			Size:       partSize,
+		})
+	}
+
+	return parts
+}