public ActionResult Subscribe(Guid userID, Guid repoID) { _logger.LogInformation("Subscribe now"); if (_userRepo.Get(userID) == null) { ModelState.AddModelError("UserError", $"UserID: {userID} not found"); return(BadRequest(ModelState)); } if (_gitRepo.Get(repoID) == null) { ModelState.AddModelError("GitRepositoryError", $"GitRepositoryID: {repoID} not found"); return(BadRequest(ModelState)); } var newSubscription = new Subscription() { UserId = userID, RepoId = repoID }; _subscriptionRepo.Save(newSubscription); return(CreatedAtAction(nameof(subscriptionsByID), new { subID = newSubscription.Id })); }