enhance: serialize user update methods

Author: eternal-flame-AD

api/user.go

@@ -9,18 +9,21 @@ import (
 	"github.com/gin-gonic/gin"
 	"github.com/gotify/server/v3/auth"
 	"github.com/gotify/server/v3/auth/password"
+	"github.com/gotify/server/v3/database"
 	"github.com/gotify/server/v3/model"
 )
 
+var errCannotDeleteLastAdmin = errors.New("cannot delete last admin")
+
 // The UserDatabase interface for encapsulating database access.
-type UserDatabase interface {
-	GetUsers() ([]*model.User, error)
+type UserDatabase[T UserDatabase[T]] interface {
+	Txn(fn func(txdb T) error) error
+	GetUsers(condition ...any) ([]*model.User, error)
 	GetUserByID(id uint) (*model.User, error)
 	GetUserByName(name string) (*model.User, error)
 	DeleteUserByID(id uint) error
 	UpdateUser(user *model.User) error
 	CreateUser(user *model.User) error
-	CountUser(condition ...any) (int64, error)
 }
 
 // UserChangeNotifier notifies listeners for user changes.
@@ -59,7 +62,7 @@ func (c *UserChangeNotifier) fireUserAdded(uid uint) error {
 
 // The UserAPI provides handlers for managing users.
 type UserAPI struct {
-	DB                 UserDatabase
+	DB                 database.GormDatabase
 	PasswordStrength   int
 	UserChangeNotifier *UserChangeNotifier
 	Registration       bool
@@ -343,19 +346,26 @@ func (a *UserAPI) DeleteUserByID(ctx *gin.Context) {
 			return
 		}
 		if user != nil {
-			adminCount, err := a.DB.CountUser(&model.User{Admin: true})
-			if success := successOrAbort(ctx, 500, err); !success {
-				return
-			}
-			if user.Admin && adminCount == 1 {
-				ctx.AbortWithError(400, errors.New("cannot delete last admin"))
-				return
-			}
-			if err := a.UserChangeNotifier.fireUserDeleted(id); err != nil {
-				ctx.AbortWithError(500, err)
-				return
+			for range 3 {
+				err = a.DB.Txn(func(txdb *database.GormDatabase) error {
+					if err := txdb.DeleteUserByID(id); err != nil {
+						return err
+					}
+					anotherAdmin, err := txdb.GetUsers(&model.User{Admin: true})
+					if err != nil {
+						return err
+					}
+					if user.Admin && len(anotherAdmin) == 0 {
+						ctx.AbortWithError(400, errCannotDeleteLastAdmin)
+						return errCannotDeleteLastAdmin
+					}
+					return a.UserChangeNotifier.fireUserDeleted(id)
+				})
+				if err == nil || ctx.IsAborted() {
+					return
+				}
 			}
-			successOrAbort(ctx, 500, a.DB.DeleteUserByID(id))
+			successOrAbort(ctx, 500, err)
 		} else {
 			ctx.AbortWithError(404, errors.New("user does not exist"))
 		}
@@ -470,15 +480,7 @@ func (a *UserAPI) UpdateUserByID(ctx *gin.Context) {
 				return
 			}
 			if dbUser != nil {
-				adminCount, err := a.DB.CountUser(&model.User{Admin: true})
-				if success := successOrAbort(ctx, 500, err); !success {
-					return
-				}
-				if !updatedUser.Admin && dbUser.Admin && adminCount == 1 {
-					ctx.AbortWithError(400, errors.New("cannot delete last admin"))
-					return
-				}
-
+				dbUserWasAdmin := dbUser.Admin
 				dbUser.Name = updatedUser.Name
 				dbUser.Admin = updatedUser.Admin
 
@@ -494,10 +496,30 @@ func (a *UserAPI) UpdateUserByID(ctx *gin.Context) {
 					}
 					dbUser.Pass = pw
 				}
-				if success := successOrAbort(ctx, 500, a.DB.UpdateUser(dbUser)); !success {
-					return
+
+				for range 3 {
+					err = a.DB.Txn(func(txdb *database.GormDatabase) error {
+						if err := txdb.UpdateUser(dbUser); err != nil {
+							return err
+						}
+
+						anotherAdmin, err := txdb.GetUsers(&model.User{Admin: true})
+						if err != nil {
+							return err
+						}
+						if !updatedUser.Admin && dbUserWasAdmin && len(anotherAdmin) == 0 {
+							ctx.AbortWithError(400, errCannotDeleteLastAdmin)
+							return errCannotDeleteLastAdmin
+						}
+
+						return nil
+					})
+
+					if err == nil || ctx.IsAborted() {
+						return
+					}
 				}
-				ctx.JSON(200, toExternalUser(dbUser))
+				successOrAbort(ctx, 500, err)
 			} else {
 				ctx.AbortWithError(404, errors.New("user does not exist"))
 			}

api/user_test.go

@@ -49,7 +49,7 @@ func (s *UserSuite) BeforeTest(suiteName, testName string) {
 		s.notifiedAdd = true
 		return nil
 	})
-	s.a = &UserAPI{DB: s.db, UserChangeNotifier: s.notifier}
+	s.a = &UserAPI{DB: *s.db.GormDatabase, UserChangeNotifier: s.notifier}
 }
 
 func (s *UserSuite) AfterTest(suiteName, testName string) {
@@ -350,17 +350,6 @@ func (s *UserSuite) Test_UpdateUserByID_InvalidID() {
 	assert.Equal(s.T(), 400, s.recorder.Code)
 }
 
-func (s *UserSuite) Test_UpdateUserByID_EmptyPassword_Expect400() {
-	s.loginAdmin()
-
-	s.ctx.Params = gin.Params{{Key: "id", Value: "1"}}
-
-	s.ctx.Request = httptest.NewRequest("POST", "/user/1", strings.NewReader(`{"name": "admin", "pass": "", "admin": false}`))
-	s.ctx.Request.Header.Set("Content-Type", "application/json")
-	s.a.UpdateUserByID(s.ctx)
-	assert.Equal(s.T(), 400, s.recorder.Code)
-}
-
 func (s *UserSuite) Test_UpdateUserByID_TooLongPassword_Expect400() {
 	s.loginAdmin()
 

database/database.go

@@ -172,14 +172,24 @@ func createDirectoryIfSqlite(dialect, connection string) {
 
 // GormDatabase is a wrapper for the gorm framework.
 type GormDatabase struct {
-	DB *gorm.DB
+	DB     *gorm.DB
+	Nested bool
 }
 
 // Close closes the gorm database connection.
 func (d *GormDatabase) Close() {
+	if d.Nested {
+		return
+	}
 	sqldb, err := d.DB.DB()
 	if err != nil {
 		return
 	}
 	sqldb.Close()
 }
+
+func (d *GormDatabase) Txn(fn func(txdb *GormDatabase) error) error {
+	return d.DB.Transaction(func(tx *gorm.DB) error {
+		return fn(&GormDatabase{DB: tx, Nested: true})
+	}, &sql.TxOptions{Isolation: sql.LevelSerializable})
+}

database/user.go

@@ -44,23 +44,19 @@ func (d *GormDatabase) GetUserByID(id uint) (*model.User, error) {
 	return nil, err
 }
 
-// CountUser returns the user count which satisfies the given condition.
-func (d *GormDatabase) CountUser(condition ...any) (int64, error) {
-	c := int64(-1)
+// GetUsers returns the users which satisfy the given condition.
+func (d *GormDatabase) GetUsers(condition ...any) ([]*model.User, error) {
+	users := make([]*model.User, 0)
 	handle := d.DB.Model(new(model.User))
 	if len(condition) == 1 {
 		handle = handle.Where(condition[0])
 	} else if len(condition) > 1 {
 		handle = handle.Where(condition[0], condition[1:]...)
 	}
-	err := handle.Count(&c).Error
-	return c, err
-}
-
-// GetUsers returns all users.
-func (d *GormDatabase) GetUsers() ([]*model.User, error) {
-	var users []*model.User
-	err := d.DB.Find(&users).Error
+	err := handle.Find(&users).Error
+	if err == gorm.ErrRecordNotFound {
+		return nil, nil
+	}
 	return users, err
 }
 

database/user_test.go

@@ -19,9 +19,10 @@ func (s *DatabaseSuite) TestUser() {
 	require.NoError(s.T(), err)
 	assert.NotNil(s.T(), jmattheis, "on bootup the first user should be automatically created")
 
-	adminCount, err := s.db.CountUser("admin = ?", true)
+	admins, err := s.db.GetUsers("admin = ?", true)
 	require.NoError(s.T(), err)
-	assert.Equal(s.T(), int64(1), adminCount, "there is initially one admin")
+	assert.Len(s.T(), admins, 1)
+	assert.True(s.T(), admins[0].Admin, "the admin user should be an admin")
 
 	users, err := s.db.GetUsers()
 	require.NoError(s.T(), err)
@@ -31,9 +32,9 @@ func (s *DatabaseSuite) TestUser() {
 	nicories := &model.User{Name: "nicories", Pass: []byte{1, 2, 3, 4}, Admin: false}
 	s.db.CreateUser(nicories)
 	assert.NotEqual(s.T(), 0, nicories.ID, "on create user a new id should be assigned")
-	userCount, err := s.db.CountUser()
+	users, err = s.db.GetUsers()
 	require.NoError(s.T(), err)
-	assert.Equal(s.T(), int64(2), userCount, "two users should exist")
+	assert.Len(s.T(), users, 2, "two users should exist")
 
 	user, err = s.db.GetUserByName("nicories")
 	require.NoError(s.T(), err)
@@ -58,9 +59,9 @@ func (s *DatabaseSuite) TestUser() {
 	require.NoError(s.T(), err)
 	assert.Len(s.T(), users, 2)
 
-	adminCount, err = s.db.CountUser(&model.User{Admin: true})
+	admins, err = s.db.GetUsers(&model.User{Admin: true})
 	require.NoError(s.T(), err)
-	assert.Equal(s.T(), int64(2), adminCount, "two admins exist")
+	assert.Len(s.T(), admins, 2, "two admins exist")
 
 	require.NoError(s.T(), s.db.DeleteUserByID(tom.ID))
 	users, err = s.db.GetUsers()

plugin/manager.go

@@ -23,7 +23,7 @@ import (
 
 // The Database interface for encapsulating database access.
 type Database interface {
-	GetUsers() ([]*model.User, error)
+	GetUsers(condition ...any) ([]*model.User, error)
 	GetPluginConfByUserAndPath(userid uint, path string) (*model.PluginConf, error)
 	CreatePluginConf(p *model.PluginConf) error
 	GetPluginConfByApplicationID(appid uint) (*model.PluginConf, error)

router/router.go

@@ -104,7 +104,7 @@ func Create(db *database.GormDatabase, vInfo *model.VersionInfo, conf *config.Co
 	}
 	sessionHandler := api.SessionAPI{DB: db, NotifyDeleted: streamHandler.NotifyDeletedClient, SecureCookie: conf.Server.SecureCookie, LocalAuthEnabled: conf.LocalAuthEnabled}
 	userChangeNotifier := new(api.UserChangeNotifier)
-	userHandler := api.UserAPI{DB: db, PasswordStrength: conf.PassStrength, UserChangeNotifier: userChangeNotifier, Registration: conf.Registration}
+	userHandler := api.UserAPI{DB: *db, PasswordStrength: conf.PassStrength, UserChangeNotifier: userChangeNotifier, Registration: conf.Registration}
 
 	pluginManager, err := plugin.NewManager(db, conf.PluginsDir, g.Group("/plugin/:id/custom/"), streamHandler)
 	if err != nil {