iceberg: cleanup metadata on non-conflict commit errors

weed/s3api/iceberg/iceberg.go

@@ -8,6 +8,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"math/rand/v2"
 	"net/http"
 	"os"
 	"path"
@@ -311,6 +312,9 @@ type setStatisticsUpdate struct {
 
 func (u *setStatisticsUpdate) asStatisticsFile() (*table.StatisticsFile, error) {
 	if u.Statistics != nil {
+		if u.Statistics.BlobMetadata == nil {
+			u.Statistics.BlobMetadata = []table.BlobMetadata{}
+		}
 		return u.Statistics, nil
 	}
 	if u.SnapshotID == nil || u.StatisticsPath == "" || u.FileSizeInBytes == nil || u.FileFooterSizeInBytes == nil {
@@ -1349,6 +1353,8 @@ func (s *Server) handleUpdateTable(w http.ResponseWriter, r *http.Request) {
 			writeError(w, http.StatusInternalServerError, "InternalServerError", "Failed to serialize metadata: "+err.Error())
 			return
 		}
+		// iceberg-go does not currently support set/remove-statistics updates in MetadataBuilder.
+		// Patch the encoded metadata JSON and parse it back to keep the response object consistent.
 		metadataBytes, err = applyStatisticsUpdates(metadataBytes, statisticsUpdates)
 		if err != nil {
 			writeError(w, http.StatusBadRequest, "BadRequestException", "Failed to apply statistics updates: "+err.Error())
@@ -1404,13 +1410,17 @@ func (s *Server) handleUpdateTable(w http.ResponseWriter, r *http.Request) {
 			}
 			if attempt < maxCommitAttempts {
 				glog.V(1).Infof("Iceberg: CommitTable conflict for %s (attempt %d/%d), retrying", tableName, attempt, maxCommitAttempts)
-				time.Sleep(time.Duration(50*attempt) * time.Millisecond)
+				jitter := time.Duration(rand.Int64N(int64(25 * time.Millisecond)))
+				time.Sleep(time.Duration(50*attempt)*time.Millisecond + jitter)
 				continue
 			}
 			writeError(w, http.StatusConflict, "CommitFailedException", "Version token mismatch")
 			return
 		}
 
+		if cleanupErr := s.deleteMetadataFile(r.Context(), metadataBucket, metadataPath, metadataFileName); cleanupErr != nil {
+			glog.V(1).Infof("Iceberg: failed to cleanup metadata file %s after update failure: %v", newMetadataLocation, cleanupErr)
+		}
 		glog.Errorf("Iceberg: CommitTable UpdateTable error: %v", err)
 		writeError(w, http.StatusInternalServerError, "InternalServerError", "Failed to commit table update: "+err.Error())
 		return