feat(canvas): 画布同步 - 新增操作事务、预演保存与并发恢复能力

backend/internal/repository/structured_storage_usage_test.go

@@ -0,0 +1,89 @@
+package repository
+
+import (
+	"errors"
+	"path/filepath"
+	"testing"
+
+	"yingce/backend/internal/model"
+
+	"gorm.io/driver/sqlite"
+	"gorm.io/gorm"
+	"gorm.io/gorm/logger"
+)
+
+func TestUserStructuredStorageUsage(t *testing.T) {
+	db, err := gorm.Open(sqlite.Open(filepath.Join(t.TempDir(), "quota.db")), &gorm.Config{Logger: logger.Default.LogMode(logger.Silent)})
+	if err != nil {
+		t.Fatal(err)
+	}
+	sqlDB, err := db.DB()
+	if err != nil {
+		t.Fatal(err)
+	}
+	sqlDB.SetMaxOpenConns(1)
+	t.Cleanup(func() { _ = sqlDB.Close() })
+	// History tables are deliberately absent: canvas quota must not read them.
+	if err := db.AutoMigrate(&model.Asset{}, &model.CanvasProject{}); err != nil {
+		t.Fatal(err)
+	}
+	repo := New(db)
+	assetPayload := `{"title":"素材 🎬"}`
+	canvasPayload := `{"title":"画布","nodes":[]}`
+	assets := []model.Asset{
+		{ID: "asset", UserID: "owner", PayloadJSON: assetPayload},
+		{ID: "empty", UserID: "owner"},
+		{ID: "null", UserID: "owner"},
+		{ID: "foreign-asset", UserID: "other", PayloadJSON: assetPayload},
+	}
+	canvases := []model.CanvasProject{
+		{ID: "canvas", UserID: "owner", PayloadJSON: canvasPayload},
+		{ID: "foreign-canvas", UserID: "other", PayloadJSON: canvasPayload},
+	}
+	if err := db.Create(&assets).Error; err != nil {
+		t.Fatal(err)
+	}
+	if err := db.Model(&model.Asset{}).Where("id = ?", "null").UpdateColumn("payload_json", nil).Error; err != nil {
+		t.Fatal(err)
+	}
+	if err := db.Create(&canvases).Error; err != nil {
+		t.Fatal(err)
+	}
+	want := UserStorageUsage{AssetCount: 3, AssetBytes: int64(len(assetPayload)), CanvasCount: 1, CanvasBytes: int64(len(canvasPayload))}
+	assertUsage := func(repo *Repository, userID string, expected UserStorageUsage) {
+		t.Helper()
+		got, err := repo.UserStructuredStorageUsage(userID)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if got != expected {
+			t.Fatalf("usage for %s = %+v, want %+v", userID, got, expected)
+		}
+	}
+	assertUsage(repo, "owner", want)
+	assertUsage(repo, "missing", UserStorageUsage{})
+	assertUsage(repo, "other", UserStorageUsage{AssetCount: 1, AssetBytes: int64(len(assetPayload)), CanvasCount: 1, CanvasBytes: int64(len(canvasPayload))})
+
+	rollback := errors.New("rollback quota probe")
+	err = repo.Transaction(func(tx *Repository) error {
+		project := model.CanvasProject{ID: "uncommitted", UserID: "owner", PayloadJSON: canvasPayload}
+		if err := tx.UpsertCanvasProject(&project); err != nil {
+			return err
+		}
+		inside := want
+		inside.CanvasCount++
+		inside.CanvasBytes += int64(len(canvasPayload))
+		assertUsage(tx, "owner", inside)
+		return rollback
+	})
+	if !errors.Is(err, rollback) {
+		t.Fatalf("transaction error = %v", err)
+	}
+	assertUsage(repo, "owner", want)
+	if err := db.Migrator().DropTable(&model.Asset{}); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := repo.UserStructuredStorageUsage("owner"); err == nil {
+		t.Fatal("database error must not become zero usage")
+	}
+}