more cart

pkg/actor/disk_storage.go

@@ -7,6 +7,7 @@ import (
 	"log"
 	"os"
 	"path/filepath"
+	"strings"
 	"sync"
 	"time"
 
@@ -201,6 +202,9 @@ func (s *DiskStorage[V]) SaveLoop(duration time.Duration) {
 }
 
 func (s *DiskStorage[V]) save() {
+	if s.queue == nil {
+		return
+	}
 	carts := 0
 	lines := 0
 	s.queue.Range(func(key, value any) bool {
@@ -295,3 +299,65 @@ func (s *DiskStorage[V]) openWriterCount() int {
 	defer s.writersMu.Unlock()
 	return len(s.writers)
 }
+
+func (s *DiskStorage[V]) PurgeOlderThan(ctx context.Context, retention time.Duration, isGrainActive func(id uint64) bool) (int, error) {
+	if err := s.ensureDir(); err != nil {
+		return 0, err
+	}
+
+	files, err := os.ReadDir(s.path)
+	if err != nil {
+		return 0, fmt.Errorf("read storage dir: %w", err)
+	}
+
+	cutoff := time.Now().Add(-retention)
+	purgedCount := 0
+
+	for _, entry := range files {
+		if entry.IsDir() {
+			continue
+		}
+		name := entry.Name()
+		if !strings.HasSuffix(name, ".events.log") {
+			continue
+		}
+
+		var id uint64
+		_, err := fmt.Sscanf(name, "%d.events.log", &id)
+		if err != nil {
+			continue
+		}
+
+		info, err := entry.Info()
+		if err != nil {
+			log.Printf("failed to get file info for %s: %v", name, err)
+			continue
+		}
+
+		if info.ModTime().Before(cutoff) {
+			// Check if grain is active in memory
+			if isGrainActive != nil && isGrainActive(id) {
+				continue
+			}
+
+			// Check if we have an active writer open
+			s.writersMu.Lock()
+			_, hasWriter := s.writers[id]
+			s.writersMu.Unlock()
+			if hasWriter {
+				continue
+			}
+
+			// Delete the file
+			fullPath := filepath.Join(s.path, name)
+			if err := os.Remove(fullPath); err != nil {
+				log.Printf("failed to delete expired cart log %s: %v", fullPath, err)
+			} else {
+				purgedCount++
+			}
+		}
+	}
+
+	return purgedCount, nil
+}
+

pkg/actor/disk_storage_test.go

@@ -2,6 +2,7 @@ package actor
 
 import (
 	"context"
+	"os"
 	"sync"
 	"testing"
 	"time"
@@ -317,3 +318,86 @@ func TestDiskStorageConcurrentWritesDifferentIDs(t *testing.T) {
 		}
 	}
 }
+
+func TestDiskStoragePurge(t *testing.T) {
+	reg := diskTestRegistry(t)
+	dir := t.TempDir()
+	storage := NewDiskStorage[testState](dir, reg)
+	t.Cleanup(storage.Close)
+
+	ctx := context.Background()
+	msg := &cart_messages.AddItem{ItemId: 1, Quantity: 1}
+
+	// Write mutations to create event logs for 1, 2, 3, 4
+	ids := []uint64{1, 2, 3, 4}
+	for _, id := range ids {
+		if err := storage.AppendMutations(id, msg); err != nil {
+			t.Fatalf("append %d: %v", id, err)
+		}
+	}
+
+	// Force save to disk
+	storage.save()
+
+	// 1. Grain 1: Old modification time, inactive, no writer -> should be purged
+	path1 := storage.logPath(1)
+	oldTime := time.Now().Add(-10 * 24 * time.Hour)
+	if err := os.Chtimes(path1, oldTime, oldTime); err != nil {
+		t.Fatal(err)
+	}
+
+	// We must close the writer for grain 1, 2, 4 to make them eligible for purging (no open writer)
+	storage.writersMu.Lock()
+	for _, id := range []uint64{1, 2, 4} {
+		if w, ok := storage.writers[id]; ok {
+			w.purged = true
+			w.file.Close()
+			delete(storage.writers, id)
+		}
+	}
+	storage.writersMu.Unlock()
+
+	// 2. Grain 2: Old mod time, but marked active -> should NOT be purged
+	path2 := storage.logPath(2)
+	if err := os.Chtimes(path2, oldTime, oldTime); err != nil {
+		t.Fatal(err)
+	}
+
+	// 3. Grain 3: Old mod time, but has open writer -> should NOT be purged
+	path3 := storage.logPath(3)
+	if err := os.Chtimes(path3, oldTime, oldTime); err != nil {
+		t.Fatal(err)
+	}
+
+	// 4. Grain 4: Recent mod time -> should NOT be purged
+	path4 := storage.logPath(4)
+
+	activeGrains := map[uint64]bool{2: true}
+	isGrainActive := func(id uint64) bool {
+		return activeGrains[id]
+	}
+
+	purged, err := storage.PurgeOlderThan(ctx, 5*24*time.Hour, isGrainActive)
+	if err != nil {
+		t.Fatalf("PurgeOlderThan failed: %v", err)
+	}
+
+	if purged != 1 {
+		t.Errorf("Expected exactly 1 purged file, got %d", purged)
+	}
+
+	// Verify file status
+	if _, err := os.Stat(path1); !os.IsNotExist(err) {
+		t.Error("Expected grain 1 log to be deleted")
+	}
+	if _, err := os.Stat(path2); err != nil {
+		t.Error("Expected grain 2 log to exist (active)")
+	}
+	if _, err := os.Stat(path3); err != nil {
+		t.Error("Expected grain 3 log to exist (active writer)")
+	}
+	if _, err := os.Stat(path4); err != nil {
+		t.Error("Expected grain 4 log to exist (recent)")
+	}
+}
+