public void OnActionExecuting(ActionExecutingContext context)
        {
            foreach (var argument in context.ActionArguments.Values.Where(v => v is RemoveUserFromChannelRequest))
            {
                RemoveUserFromChannelRequest command = argument as RemoveUserFromChannelRequest;

                _channelValidationService.RequireAuthorizedUserIsGroupAdminFromChannel(command.ChannelId);
                _channelValidationService.RequireUserIsGroupMemberFromChannel(command.Username, command.ChannelId);
                _channelValidationService.RequireUserIsChannelMember(command.Username, command.ChannelId);
            }
        }
        public IActionResult RemoveUserFromChannel(RemoveUserFromChannelRequest command)
        {
            _channelUserService.RemoveUserFromChannelByUsername(command.Username, command.ChannelId);

            return(NoContent());
        }