User repos return nil

UserRepository.go

@@ -23,21 +23,26 @@ const ClientUserPrefix = "cu"
 
 const UserScanBatchSize = 500
 
-func (repository *UserRepository) SaveUser(clientUserId string, student *models.Student) (err error, hasChanges bool) {
+func (repository *UserRepository) SaveUser(clientUserId string, student *models.Student) (error, bool) {
 	previousStudent := repository.GetStudent(clientUserId)
 
 	studentSerialized, err := proto.Marshal(student)
 	ctx := context.Background()
 
+	hasChanges := previousStudent != student
+	if previousStudent != nil && student != nil {
+		hasChanges = previousStudent.Id != student.Id
+	}
+
 	if err == nil {
 		clientUserKey := repository.getClientUserKey(clientUserId)
 		pipe := repository.redis.TxPipeline()
 
-		if previousStudent.Id != student.Id && previousStudent.Id != 0 {
+		if hasChanges && previousStudent != nil {
 			pipe.SRem(ctx, repository.getStudentKey(previousStudent.Id), clientUserId)
 		}
 
-		if student.Id == 0 {
+		if student == nil || student.Id == 0 {
 			pipe.Del(ctx, clientUserKey)
 		} else {
 			pipe.Set(ctx, clientUserKey, studentSerialized, UserExpiration)
@@ -49,7 +54,7 @@ func (repository *UserRepository) SaveUser(clientUserId string, student *models.
 		_, err = pipe.Exec(ctx)
 	}
 
-	return err, previousStudent.Id != student.Id
+	return err, hasChanges
 }
 
 func (repository *UserRepository) Commit() error {
@@ -68,16 +73,16 @@ func (repository *UserRepository) GetStudent(clientUserId string) *models.Studen
 		UserExpiration,
 	).Bytes()
 
-	student := &models.Student{}
 	if studentSerialized != nil && len(studentSerialized) > 0 {
-		_ = proto.Unmarshal(studentSerialized, student)
-	}
-
-	if student.Id != 0 {
-		repository.redis.Expire(ctx, repository.getStudentKey(student.Id), UserExpiration)
+		student := models.Student{}
+		_ = proto.Unmarshal(studentSerialized, &student)
+		if student.Id != 0 {
+			repository.redis.Expire(ctx, repository.getStudentKey(student.Id), UserExpiration)
+			return &student
+		}
 	}
 
-	return student
+	return nil
 }
 
 func (repository *UserRepository) GetClientUserIds(studentId uint) []string {

UserRepository_test.go

@@ -252,7 +252,7 @@ func TestUserRepository_SaveUser(t *testing.T) {
 		assert.NoError(t, err)
 
 		actualStudent = userRepository.GetStudent(expectedClientUserId)
-		assert.Equal(t, emptyStudent.String(), actualStudent.String())
+		assert.Nil(t, actualStudent)
 
 		actualClientIds = userRepository.GetClientUserIds(uint(expectedStudent1.Id))
 		assert.Len(t, actualClientIds, 0)
@@ -311,7 +311,7 @@ func TestUserRepository_GetStudent(t *testing.T) {
 		redisMock.ExpectGetEx(clientUserId, UserExpiration).RedisNil()
 
 		actualStudent := userRepository.GetStudent(clientUserId)
-		assertStudent(t, &models.Student{}, actualStudent)
+		assert.Nil(t, actualStudent)
 	})
 }