Written by: Ismaël Diakité
Date Published: 28 November 2023

Fetching Azure AD Groups and Users with Microsoft Graph SDK in C#

This tutorial demonstrates how to retrieve groups and users from Azure Active Directory (AAD) using the Microsoft Graph SDK in C#. We'll be using PageIterator for efficient data retrieval and Parallel.ForEach for concurrent processing.

Prerequisites

• Azure Active Directory Tenant
• Registered Azure AD Application with Client ID and Secret
• Required API permissions in Azure AD for Microsoft Graph (Group.Read.All and User.Read.All)
• .NET development environment with Azure SDK and Microsoft Graph SDK

Step 1: Setting Up the Environment

First, include the necessary namespaces:

using Azure.Core;
using Azure.Identity;
using Microsoft.Graph;
using Microsoft.Graph.Models;
using System.Collections.Concurrent;

Step 2: Initialize Authentication

To initialize authentication, you need to define the following variables in your code and replace the placeholders with your actual values:

string tenantId = "YOUR TENANT ID HERE";
string clientId = "YOUR CLIENT ID HERE";
string clientSecret = "YOUR CLIENT SECRET HERE";

Step 3: Create a GraphServiceClient

To create a GraphServiceClient instance using ClientSecretCredential, follow these steps:

var scopes = new[] { "https://graph.microsoft.com/.default" };
var options = new TokenCredentialOptions
{
    AuthorityHost = AzureAuthorityHosts.AzurePublicCloud
};

var clientSecretCredential = new ClientSecretCredential(tenantId, clientId, clientSecret, options);

// Optional: Get access token to verify authentication
var accessToken = await clientSecretCredential.GetTokenAsync(new TokenRequestContext(scopes) { });
Console.WriteLine(accessToken.Token);

var graphClient = new GraphServiceClient(clientSecretCredential, scopes);

Step 4: Retrieve and Process Groups

To retrieve and process groups using the GetGroupsAsync method and process them in parallel, follow these steps:

var groupsList = await GetGroupsAsync(graphClient);

Parallel.ForEach(groupsList!, group =>
{
    Console.WriteLine(group.DisplayName);
});

Step 5: Retrieve and Process Users

To retrieve and process users using the GetUsersAsync method and process them in parallel, follow these steps:

var usersList = await GetUsersAsync(graphClient);

Parallel.ForEach(usersList!, user =>
{
    Console.WriteLine(user.DisplayName);
});

Auxiliary Methods

GetGroupsAsync Method

The GetGroupsAsync method is designed to fetch all groups from Azure Active Directory (AAD) using a PageIterator. Below is the code for this method:

async Task<ConcurrentBag<Group>?> GetGroupsAsync(GraphServiceClient graphClient)
{
    var groupsList = new ConcurrentBag<Group>();

    var requestGroup = graphClient.Groups
        .GetAsync()
        .GetAwaiter()
        .GetResult();

    if (requestGroup is null)
    {
        Console.WriteLine("No group found in Azure AD");
        return null;
    }

    var pageIterator = PageIterator<Group, GroupCollectionResponse>
        .CreatePageIterator(graphClient, requestGroup,
        group =>
        {
            groupsList.Add(group);
            return true;
        });
    await pageIterator.IterateAsync();

    return groupsList;
}

GetUsersAsync Method

The GetUsersAsync method is designed to fetch all users from Azure Active Directory (AD) using a PageIterator. Below is the code for this method:

async Task<ConcurrentBag<User>?> GetUsersAsync(GraphServiceClient graphClient)
{
    var usersList = new ConcurrentBag<User>();

    var requestUser = graphClient.Users
        .GetAsync()
        .GetAwaiter()
        .GetResult();

    if (requestUser is null)
    {
        Console.WriteLine("No user found in Azure AD");
        return null;
    }

    var pageIterator = PageIterator<User, UserCollectionResponse>
        .CreatePageIterator(graphClient, requestUser,
        user =>
        {
            usersList.Add(user);
            return true;
        });
    await pageIterator.IterateAsync();

    return usersList;
}

Conclusion

This tutorial demonstrated how to retrieve groups and users from Azure Active Directory (AAD) using the Microsoft Graph SDK in C#. We used PageIterator for efficient data retrieval and Parallel.ForEach for concurrent processing.

Full Source Code

The complete source code for this project can be found at the following GitHub repository: FetchGroupsAndUsersAAD