From fb3dc6a695889c0fc3eabfa7cde65976cb13f7a3 Mon Sep 17 00:00:00 2001
From: Chris Lu <chris.lu@gmail.com>
Date: Mon, 9 Feb 2026 22:32:53 -0800
Subject: [PATCH] iceberg: refine commit retry and statistics patching

---
 weed/s3api/iceberg/iceberg.go                 | 47 ++++++++++++-------
 .../iceberg/iceberg_commit_updates_test.go    |  8 +++-
 2 files changed, 38 insertions(+), 17 deletions(-)

diff --git a/weed/s3api/iceberg/iceberg.go b/weed/s3api/iceberg/iceberg.go
index 10c0f4b14..f0b4703f8 100644
--- a/weed/s3api/iceberg/iceberg.go
+++ b/weed/s3api/iceberg/iceberg.go
@@ -292,6 +292,8 @@ type statisticsUpdate struct {
 	remove *int64
 }
 
+var ErrIncompleteSetStatistics = errors.New("set-statistics requires snapshot-id, statistics-path, file-size-in-bytes, and file-footer-size-in-bytes")
+
 type commitAction struct {
 	Action string `json:"action"`
 }
@@ -312,7 +314,7 @@ func (u *setStatisticsUpdate) asStatisticsFile() (*table.StatisticsFile, error)
 		return u.Statistics, nil
 	}
 	if u.SnapshotID == nil || u.StatisticsPath == "" || u.FileSizeInBytes == nil || u.FileFooterSizeInBytes == nil {
-		return nil, errors.New("set-statistics requires snapshot-id, statistics-path, file-size-in-bytes, and file-footer-size-in-bytes")
+		return nil, ErrIncompleteSetStatistics
 	}
 
 	stats := &table.StatisticsFile{
@@ -400,27 +402,38 @@ func applyStatisticsUpdates(metadataBytes []byte, updates []statisticsUpdate) ([
 		}
 	}
 
+	statisticsBySnapshot := make(map[int64]table.StatisticsFile, len(statistics))
+	orderedSnapshotIDs := make([]int64, 0, len(statistics))
+	inOrder := make(map[int64]bool, len(statistics))
+	for _, stat := range statistics {
+		statisticsBySnapshot[stat.SnapshotID] = stat
+		if !inOrder[stat.SnapshotID] {
+			orderedSnapshotIDs = append(orderedSnapshotIDs, stat.SnapshotID)
+			inOrder[stat.SnapshotID] = true
+		}
+	}
+
 	for _, update := range updates {
 		if update.set != nil {
-			next := make([]table.StatisticsFile, 0, len(statistics)+1)
-			for _, existing := range statistics {
-				if existing.SnapshotID != update.set.SnapshotID {
-					next = append(next, existing)
-				}
+			statisticsBySnapshot[update.set.SnapshotID] = *update.set
+			if !inOrder[update.set.SnapshotID] {
+				orderedSnapshotIDs = append(orderedSnapshotIDs, update.set.SnapshotID)
+				inOrder[update.set.SnapshotID] = true
 			}
-			next = append(next, *update.set)
-			statistics = next
 			continue
 		}
 		if update.remove != nil {
-			next := make([]table.StatisticsFile, 0, len(statistics))
-			for _, existing := range statistics {
-				if existing.SnapshotID != *update.remove {
-					next = append(next, existing)
-				}
-			}
-			statistics = next
+			delete(statisticsBySnapshot, *update.remove)
+		}
+	}
+
+	statistics = make([]table.StatisticsFile, 0, len(statisticsBySnapshot))
+	for _, snapshotID := range orderedSnapshotIDs {
+		stat, ok := statisticsBySnapshot[snapshotID]
+		if !ok {
+			continue
 		}
+		statistics = append(statistics, stat)
 	}
 
 	if len(statistics) == 0 {
@@ -1249,6 +1262,7 @@ func (s *Server) handleUpdateTable(w http.ResponseWriter, r *http.Request) {
 	}
 
 	maxCommitAttempts := 3
+	generatedLegacyUUID := uuid.New()
 	for attempt := 1; attempt <= maxCommitAttempts; attempt++ {
 		getReq := &s3tables.GetTableRequest{
 			TableBucketARN: bucketARN,
@@ -1282,7 +1296,7 @@ func (s *Server) handleUpdateTable(w http.ResponseWriter, r *http.Request) {
 			}
 		}
 		if tableUUID == uuid.Nil {
-			tableUUID = uuid.New()
+			tableUUID = generatedLegacyUUID
 		}
 
 		var currentMetadata table.Metadata
@@ -1390,6 +1404,7 @@ 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)
 				continue
 			}
 			writeError(w, http.StatusConflict, "CommitFailedException", "Version token mismatch")
diff --git a/weed/s3api/iceberg/iceberg_commit_updates_test.go b/weed/s3api/iceberg/iceberg_commit_updates_test.go
index e583d4216..96ed7e402 100644
--- a/weed/s3api/iceberg/iceberg_commit_updates_test.go
+++ b/weed/s3api/iceberg/iceberg_commit_updates_test.go
@@ -39,10 +39,13 @@ func TestParseCommitUpdatesRejectsIncompleteSetStatistics(t *testing.T) {
 	if err == nil {
 		t.Fatalf("parseCommitUpdates() expected error")
 	}
+	if !errors.Is(err, ErrIncompleteSetStatistics) {
+		t.Fatalf("parseCommitUpdates() error = %v, want ErrIncompleteSetStatistics", err)
+	}
 }
 
 func TestApplyStatisticsUpdatesUpsertAndRemove(t *testing.T) {
-	metadata := []byte(`{"format-version":2,"statistics":[{"snapshot-id":1,"statistics-path":"s3://bucket/stats-1.puffin","file-size-in-bytes":10,"file-footer-size-in-bytes":1,"blob-metadata":[]}]} `)
+	metadata := []byte(`{"format-version":2,"statistics":[{"snapshot-id":1,"statistics-path":"s3://bucket/stats-1.puffin","file-size-in-bytes":10,"file-footer-size-in-bytes":1,"blob-metadata":[]},{"snapshot-id":2,"statistics-path":"s3://bucket/stats-2.puffin","file-size-in-bytes":20,"file-footer-size-in-bytes":2,"blob-metadata":[]}]} `)
 
 	snapshotID := int64(2)
 	setUpdates := []statisticsUpdate{
@@ -74,6 +77,9 @@ func TestApplyStatisticsUpdatesUpsertAndRemove(t *testing.T) {
 	if got := int64(stats[0]["snapshot-id"].(float64)); got != 1 {
 		t.Fatalf("remaining snapshot-id = %d, want 1", got)
 	}
+	if got := int64(stats[0]["file-size-in-bytes"].(float64)); got != 11 {
+		t.Fatalf("remaining file-size-in-bytes = %d, want 11", got)
+	}
 }
 
 var statisticsFileForTest = table.StatisticsFile{