feat(canvas): 绘图工具支持自定义 tldraw License Key (#100)

* feat(canvas): 绘图工具 - 支持自定义 tldraw License Key

* docs(canvas): 绘图工具 - 添加 License Key 页面截图

backend/internal/repository/repository.go

@@ -590,6 +590,17 @@ func (r *Repository) SaveSystemSetting(setting *model.SystemSetting) error {
 	return r.db.Save(setting).Error
 }
 
+func (r *Repository) SaveSystemSettings(settings ...*model.SystemSetting) error {
+	return r.db.Transaction(func(tx *gorm.DB) error {
+		for _, setting := range settings {
+			if err := tx.Save(setting).Error; err != nil {
+				return err
+			}
+		}
+		return nil
+	})
+}
+
 func (r *Repository) DeleteSystemSetting(key string) error {
 	return r.db.Delete(&model.SystemSetting{}, "key = ?", key).Error
 }

backend/internal/service/drawing_engine.go

@@ -11,7 +11,10 @@ import (
 	"gorm.io/gorm"
 )
 
-const drawingEngineSettingKey = "drawing_engine"
+const (
+	drawingEngineSettingKey    = "drawing_engine"
+	tldrawLicenseKeySettingKey = "tldraw_license_key"
+)
 
 const (
 	DrawingEngineTldraw     = "tldraw"
@@ -19,7 +22,8 @@ const (
 )
 
 type DrawingEngineSetting struct {
-	DefaultEngine string `json:"defaultEngine"`
+	DefaultEngine    string `json:"defaultEngine"`
+	TldrawLicenseKey string `json:"tldrawLicenseKey"`
 }
 
 type PublicDrawingEngineSetting struct {
@@ -57,11 +61,22 @@ func (s *Service) UpdateDrawingEngineSetting(actor *model.User, value DrawingEng
 	if err := validateDrawingEngineSetting(value); err != nil {
 		return nil, err
 	}
+	value.TldrawLicenseKey = strings.TrimSpace(value.TldrawLicenseKey)
 	current, before, err := s.readDrawingEngineSetting()
 	if err != nil {
 		return nil, err
 	}
-	encoded, err := json.Marshal(value)
+	currentLicenseSetting, _, err := s.readTldrawLicenseKey()
+	if err != nil {
+		return nil, err
+	}
+	encoded, err := json.Marshal(struct {
+		DefaultEngine string `json:"defaultEngine"`
+	}{DefaultEngine: value.DefaultEngine})
+	if err != nil {
+		return nil, err
+	}
+	encodedLicenseKey, err := json.Marshal(value.TldrawLicenseKey)
 	if err != nil {
 		return nil, err
 	}
@@ -69,10 +84,14 @@ func (s *Service) UpdateDrawingEngineSetting(actor *model.User, value DrawingEng
 	if current != nil {
 		setting.CreatedAt = current.CreatedAt
 	}
-	if err := s.repo.SaveSystemSetting(&setting); err != nil {
+	licenseSetting := model.SystemSetting{Key: tldrawLicenseKeySettingKey, ValueJSON: string(encodedLicenseKey), UpdatedBy: actor.ID}
+	if currentLicenseSetting != nil {
+		licenseSetting.CreatedAt = currentLicenseSetting.CreatedAt
+	}
+	if err := s.repo.SaveSystemSettings(&setting, &licenseSetting); err != nil {
 		return nil, err
 	}
-	if err := s.appendAdminAudit(actor, "drawing_engine.update", "system_setting", drawingEngineSettingKey, "更新默认绘图工具", map[string]any{"before": before, "after": value}); err != nil {
+	if err := s.appendAdminAudit(actor, "drawing_engine.update", "system_setting", drawingEngineSettingKey, "更新绘图工具配置", map[string]any{"before": drawingEngineAuditValue(before), "after": drawingEngineAuditValue(value)}); err != nil {
 		return nil, err
 	}
 	return publicDrawingEngineSetting(&setting, value), nil
@@ -80,22 +99,42 @@ func (s *Service) UpdateDrawingEngineSetting(actor *model.User, value DrawingEng
 
 func (s *Service) readDrawingEngineSetting() (*model.SystemSetting, DrawingEngineSetting, error) {
 	setting, err := s.repo.SystemSetting(drawingEngineSettingKey)
+	value := defaultDrawingEngineSetting()
 	if errors.Is(err, gorm.ErrRecordNotFound) {
-		return nil, defaultDrawingEngineSetting(), nil
+		setting = nil
+	} else if err != nil {
+		return nil, DrawingEngineSetting{}, err
+	} else {
+		if strings.TrimSpace(setting.ValueJSON) == "" || json.Unmarshal([]byte(setting.ValueJSON), &value) != nil {
+			return nil, DrawingEngineSetting{}, errors.New("绘图工具配置格式无效")
+		}
+		if err := validateDrawingEngineSetting(value); err != nil {
+			return nil, DrawingEngineSetting{}, err
+		}
 	}
+	_, licenseKey, err := s.readTldrawLicenseKey()
 	if err != nil {
 		return nil, DrawingEngineSetting{}, err
 	}
-	value := DrawingEngineSetting{}
-	if strings.TrimSpace(setting.ValueJSON) == "" || json.Unmarshal([]byte(setting.ValueJSON), &value) != nil {
-		return nil, DrawingEngineSetting{}, errors.New("绘图工具配置格式无效")
-	}
-	if err := validateDrawingEngineSetting(value); err != nil {
-		return nil, DrawingEngineSetting{}, err
-	}
+	value.TldrawLicenseKey = licenseKey
 	return setting, value, nil
 }
 
+func (s *Service) readTldrawLicenseKey() (*model.SystemSetting, string, error) {
+	setting, err := s.repo.SystemSetting(tldrawLicenseKeySettingKey)
+	if errors.Is(err, gorm.ErrRecordNotFound) {
+		return nil, "", nil
+	}
+	if err != nil {
+		return nil, "", err
+	}
+	var value string
+	if strings.TrimSpace(setting.ValueJSON) == "" || json.Unmarshal([]byte(setting.ValueJSON), &value) != nil {
+		return nil, "", errors.New("tldraw License Key 配置格式无效")
+	}
+	return setting, strings.TrimSpace(value), nil
+}
+
 func validateDrawingEngineSetting(value DrawingEngineSetting) error {
 	if value.DefaultEngine != DrawingEngineTldraw && value.DefaultEngine != DrawingEngineExcalidraw {
 		return BadAuthRequest("默认绘图工具必须是 tldraw 或 Excalidraw")
@@ -103,6 +142,10 @@ func validateDrawingEngineSetting(value DrawingEngineSetting) error {
 	return nil
 }
 
+func drawingEngineAuditValue(value DrawingEngineSetting) map[string]any {
+	return map[string]any{"defaultEngine": value.DefaultEngine, "hasTldrawLicenseKey": strings.TrimSpace(value.TldrawLicenseKey) != ""}
+}
+
 func publicDrawingEngineSetting(setting *model.SystemSetting, value DrawingEngineSetting) *PublicDrawingEngineSetting {
 	result := &PublicDrawingEngineSetting{DrawingEngineSetting: value, Configured: setting != nil}
 	if setting != nil {

backend/internal/service/drawing_engine_test.go

@@ -1,6 +1,16 @@
 package service
 
-import "testing"
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+
+	"infinite-canvas/backend/internal/model"
+	"infinite-canvas/backend/internal/repository"
+
+	"gorm.io/driver/sqlite"
+	"gorm.io/gorm"
+)
 
 func TestDefaultDrawingEngineUsesExcalidraw(t *testing.T) {
 	setting := defaultDrawingEngineSetting()
@@ -19,3 +29,53 @@ func TestValidateDrawingEngineSetting(t *testing.T) {
 		t.Fatal("validate unknown engine = nil")
 	}
 }
+
+func TestUpdateDrawingEngineSettingKeepsDefaultEngineAndStoresTldrawLicenseSeparately(t *testing.T) {
+	db, err := gorm.Open(sqlite.Open(":memory:"), &gorm.Config{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if sqlDB, err := db.DB(); err == nil {
+		sqlDB.SetMaxOpenConns(1)
+	}
+	if err := db.AutoMigrate(&model.SystemSetting{}, &model.AdminAuditEvent{}); err != nil {
+		t.Fatal(err)
+	}
+	repo := repository.New(db)
+	svc := New(repo, t.TempDir())
+	actor := &model.User{ID: "admin-1", Role: model.UserRoleAdmin}
+
+	setting, err := svc.UpdateDrawingEngineSetting(actor, DrawingEngineSetting{
+		DefaultEngine:    DrawingEngineExcalidraw,
+		TldrawLicenseKey: "license-key-for-test",
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if setting.DefaultEngine != DrawingEngineExcalidraw {
+		t.Fatalf("default engine = %q, want %q", setting.DefaultEngine, DrawingEngineExcalidraw)
+	}
+	if setting.TldrawLicenseKey != "license-key-for-test" {
+		t.Fatalf("license key = %q", setting.TldrawLicenseKey)
+	}
+
+	licenseSetting, err := repo.SystemSetting(tldrawLicenseKeySettingKey)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var savedLicenseKey string
+	if err := json.Unmarshal([]byte(licenseSetting.ValueJSON), &savedLicenseKey); err != nil {
+		t.Fatal(err)
+	}
+	if savedLicenseKey != "license-key-for-test" {
+		t.Fatalf("stored license key = %q", savedLicenseKey)
+	}
+
+	engineSetting, err := repo.SystemSetting(drawingEngineSettingKey)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if strings.Contains(engineSetting.ValueJSON, "license-key-for-test") {
+		t.Fatalf("drawing engine setting must not contain the license key: %s", engineSetting.ValueJSON)
+	}
+}