public async Task GetMembershipInformation_ShouldReturnNull_WhenGroupDoesntExist()
        {
            // Arrange
            _unitOfWork.Setup(x => x.Groups.GetById(It.IsAny <int>()))
            .ReturnsAsync(() => null);

            // Act
            var result = await _sut.GetMembershipInformation(It.IsAny <int>(), It.IsAny <int>());

            // Assert
            Assert.Null(result);
        }
        public async Task <IActionResult> GetMembershipInformation(int userId, int groupId)
        {
            if (userId != int.Parse(User.FindFirst(ClaimTypes.NameIdentifier).Value))
            {
                return(Unauthorized());
            }

            var membershipInformation = await _groupsService.GetMembershipInformation(userId, groupId);

            if (membershipInformation != null)
            {
                return(Ok(membershipInformation));
            }

            return(BadRequest());
        }