Azure Graph service not finding newly created user - azure-active-directory

Question

I have a web application that uses Azure ACS and Azure AD to handle our authentication.
We have a user management feature in the web application that allows a user to create new users. This takes the details such as username, password, email etc. and uses the graph service to create a user in azure.
var newUser = new Microsoft.WindowsAzure.ActiveDirectory.User
{
userPrincipalName = user.UserName,
mailNickname = user.MailNickname,
accountEnabled = true,
displayName = user.FirstName + " " + user.Surname,
givenName = user.FirstName,
surname = user.Surname
};
newUser.passwordProfile = new PasswordProfile
{
forceChangePasswordNextLogin = false,
password = user.Password
};
var graphService = GetGraphService(tenantName);
graphService.AddTousers(newUser);
graphService.SaveChanges();
We are then required to create a record in the web application database for this user. The record needs the object ID from azure. So we use the graphService to get the newly-created user details. This is where my problem lies. It doesn't find the user.
private string GetObjectIdFromAzure(string userName, string tenantName)
{
var graphService = GetGraphService(tenantName);
var users = graphService.users;
QueryOperationResponse<Microsoft.WindowsAzure.ActiveDirectory.User> response;
response = users.Execute() as QueryOperationResponse<Microsoft.WindowsAzure.ActiveDirectory.User>;
var user = response.FirstOrDefault(x => x.userPrincipalName == userName);
return user != null ? user.objectId : "";
}
My code was working without any issues for a few months and only today I am having issues. What frustrates me more it that I have another deployment of the same code where it works without any issues. Some differences between the two deployments are:
The deployments use different Access control namespaces in Azure
The deployments have separate applications in Azure AD
One is https, one is http
The users for both system are under the same Directory.
I have put in logging in both deployments to get the number of users returned by
users.Execute()
In both systems it reported 100 (they share the same users)
Any ideas of what would cause this to stop working? I didn't change any code relating to this recently, I haven't changed any configuration on Azure and I didn't change the web.config of the application

Answer 1

The problem was caused by the fact that I was filtering the users after retrieving them. The graph API was only returning a maximum of 100 users.
So the process was like so:
User created in Azure
Success message returned
Web App searches Azure for user to get Object ID
Graph Api only returns top 100 users. User was not in top 100 alphabetically so error thrown
The reason it was working on our second deployment was that I was prefixing the user name with demo_ (we use this site to demo new features before releasing). This meant that it was being returned in the top 100 users.
I changed the code as follows so it filters during the retrieval instead of after:
private Microsoft.WindowsAzure.ActiveDirectory.User GetUserFromAzure(string userName, string tenantName, out DirectoryDataService graphService)
{
graphService = GetGraphService(tenantName);
var users = (DataServiceQuery<Microsoft.WindowsAzure.ActiveDirectory.User>)graphService.users.Where(x => x.userPrincipalName == userName);
QueryOperationResponse<Microsoft.WindowsAzure.ActiveDirectory.User> response;
response = users.Execute() as QueryOperationResponse<Microsoft.WindowsAzure.ActiveDirectory.User>;
var user = response.FirstOrDefault();
return user;
}