To access Azure Active Directory (AAD) programmatically, you can utilize the Microsoft Authentication Library (MSAL), which is designed to handle token acquisitions and manage session states seamlessly. Begin by registering your application in the Azure portal to obtain the necessary credentials, including the client ID, tenant ID, and client secret if required. Once your app is registered, you can use MSAL to authenticate users and request tokens for accessing different AAD resources such as Microsoft Graph API. The following sample demonstrates how to acquire an access token using MSAL in a Node.js environment:

“`javascript
const msal = require(‘@azure/msal-node’);
const msalConfig = {
auth: {
clientId: ‘YOUR_CLIENT_ID’,
authority: ‘https://login.microsoftonline.com/YOUR_TENANT_ID’,
clientSecret: ‘YOUR_CLIENT_SECRET’, // if applicable
},
};

const cca = new msal.ConfidentialClientApplication(msalConfig);
const clientCredentialRequest = {
scopes: [‘https://graph.microsoft.com/.default’],
};

cca.acquireTokenByClientCredential(clientCredentialRequest)
.then(response => {
console.log(“Access Token:”, response.accessToken);
})
.catch(error => {
console.log(error);
});
“`

After acquiring the access token, you can leverage it to make authenticated requests to the Microsoft Graph API or any other AAD-secured resource. You can use libraries such as Axios or Fetch API to facilitate these requests. For instance, to retrieve user details, simply include the access token in the Authorization header of your HTTP request. Here is an example using Axios to get user information:

“`javascript
const axios = require(‘axios’);

axios.get(‘https://graph.microsoft.com/v1.0/me’, {
headers: {
Authorization: `Bearer ${response.accessToken}`,
},
}).then(res => {
console.log(“User Information:”, res.data);
}).catch(error => {
console.error(“Error fetching user data:”, error);
});
“`

By following these steps, you can efficiently work with Azure Active Directory using MSAL and access Microsoft Graph or other services with ease, benefitting from the robust features included in the Azure ecosystem.