Quickstart: Acquire a token and call Microsoft Graph from a Java daemon app

Articol
10/23/2023

In this quickstart, you download and run a code sample that demonstrates how a Java application can get an access token using the app's identity to call the Microsoft Graph API and display a list of users in the directory. The code sample demonstrates how an unattended job or Windows service can run with an application identity, instead of a user's identity.

Diagram showing how the sample app generated by this quickstart works.

Prerequisites

To run this sample, you need:

Java Development Kit (JDK) 8 or greater
Maven

Register and download your quickstart app

Tip

Steps in this article might vary slightly based on the portal you start from.

Step 1: Register the application

To register your application and add the app's registration information to your solution manually, follow these steps:

Sign in to the Microsoft Entra admin center as at least an Application Developer.
If you have access to multiple tenants, use the Settings icon in the top menu to switch to the tenant in which you want to register the application from the Directories + subscriptions menu.
Browse to Identity > Applications > Application registrations.
Select New registration.
Enter a Name for your application, for example Daemon-console. Users of your app might see this name, and you can change it later.
Select Register.
Under Manage, select Certificates & secrets.
Under Client secrets, select New client secret, enter a name, and then select Add. Record the secret value in a safe location for use in a later step.
Under Manage, select API Permissions > Add a permission. Select Microsoft Graph.
Select Application permissions.
Under User node, select User.Read.All, then select Add permissions.

Step 2: Download the Java project

Download the Java daemon project

Step 3: Configure the Java project

Extract the zip file to a local folder close to the root of the disk, such as C:\Azure-Samples.
Navigate to the msal-client-credential-secret subfolder.
Edit src\main\resources\application.properties and replace the values of the fields AUTHORITY, CLIENT_ID, and SECRET with the following snippet:

  AUTHORITY=https://login.microsoftonline.com/Enter_the_Tenant_Id_Here/
  CLIENT_ID=Enter_the_Application_Id_Here
  SECRET=Enter_the_Client_Secret_Here

Where:

Enter_the_Application_Id_Here - is the Application (client) ID for the application you registered.
Enter_the_Tenant_Id_Here - replace this value with the Tenant Id or Tenant name (for example, contoso.microsoft.com).
Enter_the_Client_Secret_Here - replace this value with the client secret created on step 1.

Tip

To find the values of Application (client) ID, Directory (tenant) ID, go to the app's Overview page. To generate a new key, go to Certificates & secrets page.

If you try to run the application at this point, you'll receive HTTP 403 - Forbidden error: Insufficient privileges to complete the operation. This error happens because any app-only permission requires Admin consent: a Global Administrator of your directory must give consent to your application. Select one of the options below depending on your role:

Global tenant administrator

If you are a global tenant administrator, go to API Permissions page in App registrations and select Grant admin consent for {Tenant Name} (Where {Tenant Name} is the name of your directory).

Standard user

If you're a standard user of your tenant, then you need to ask a Global Administrator to grant admin consent for your application. To do this, give the following URL to your administrator:

https://login.microsoftonline.com/Enter_the_Tenant_Id_Here/adminconsent?client_id=Enter_the_Application_Id_Here

Where:

Enter_the_Tenant_Id_Here - replace this value with the Tenant Id or Tenant name (for example, contoso.microsoft.com)
Enter_the_Application_Id_Here - is the Application (client) ID for the application you registered.

Step 5: Run the application

You can test the sample directly by running the main method of ClientCredentialGrant.java from your IDE.

From your shell or command line:

$ mvn clean compile assembly:single

This will generate a msal-client-credential-secret-1.0.0.jar file in your /targets directory. Run this using your Java executable like below:

$ java -jar msal-client-credential-secret-1.0.0.jar

After running, the application should display the list of users in the configured tenant.

Important

This quickstart application uses a client secret to identify itself as confidential client. Because the client secret is added as a plain-text to your project files, for security reasons, it is recommended that you use a certificate instead of a client secret before considering the application as production application. For more information on how to use a certificate, see these instructions in the same GitHub repository for this sample, but in the second folder MSAL-client-credential-certificate.

More information

MSAL Java

MSAL Java is the library used to sign in users and request tokens used to access an API protected by Microsoft identity platform. As described, this quickstart requests tokens by using the application own identity instead of delegated permissions. The authentication flow used in this case is known as client credentials oauth flow. For more information on how to use MSAL Java with daemon apps, see this article.

Add MSAL4J to your application by using Maven or Gradle to manage your dependencies by making the following changes to the application's pom.xml (Maven) or build.gradle (Gradle) file.

In pom.xml:

<dependency>
    <groupId>com.microsoft.azure</groupId>
    <artifactId>msal4j</artifactId>
    <version>1.0.0</version>
</dependency>

In build.gradle:

compile group: 'com.microsoft.azure', name: 'msal4j', version: '1.0.0'

MSAL initialization

Add a reference to MSAL for Java by adding the following code to the top of the file where you will be using MSAL4J:

import com.microsoft.aad.msal4j.*;

Then, initialize MSAL using the following code:

IClientCredential credential = ClientCredentialFactory.createFromSecret(CLIENT_SECRET);

ConfidentialClientApplication cca =
        ConfidentialClientApplication
                .builder(CLIENT_ID, credential)
                .authority(AUTHORITY)
                .build();

Where:	Description
`CLIENT_SECRET`	Is the client secret created for the application.
`CLIENT_ID`	Is the Application (client) ID for the registered application. You can find this value in the app's Overview page.
`AUTHORITY`	The STS endpoint for user to authenticate. Usually `https://login.microsoftonline.com/{tenant}` for public cloud, where {tenant} is the name of your tenant or your tenant ID.

Requesting tokens

To request a token using app's identity, use acquireToken method:

IAuthenticationResult result;
     try {
         SilentParameters silentParameters =
                 SilentParameters
                         .builder(SCOPE)
                         .build();

         // try to acquire token silently. This call will fail since the token cache does not
         // have a token for the application you are requesting an access token for
         result = cca.acquireTokenSilently(silentParameters).join();
     } catch (Exception ex) {
         if (ex.getCause() instanceof MsalException) {

             ClientCredentialParameters parameters =
                     ClientCredentialParameters
                             .builder(SCOPE)
                             .build();

             // Try to acquire a token. If successful, you should see
             // the token information printed out to console
             result = cca.acquireToken(parameters).join();
         } else {
             // Handle other exceptions accordingly
             throw ex;
         }
     }
     return result;

Where: Description

SCOPE Contains the scopes requested. For confidential clients, this should use the format similar to {Application ID URI}/.default to indicate that the scopes being requested are the ones statically defined in the app object (for Microsoft Graph, {Application ID URI} points to https://graph.microsoft.com). For custom web APIs, {Application ID URI} is defined under the Expose an API section in App registrations.

Where:	Description
`SCOPE`	Contains the scopes requested. For confidential clients, this should use the format similar to `{Application ID URI}/.default` to indicate that the scopes being requested are the ones statically defined in the app object (for Microsoft Graph, `{Application ID URI}` points to `https://graph.microsoft.com`). For custom web APIs, `{Application ID URI}` is defined under the Expose an API section in App registrations.

Help and support

If you need help, want to report an issue, or want to learn about your support options, see Help and support for developers.

Next steps

To learn more about daemon applications, see the scenario landing page.

Daemon application that calls web APIs

Partajați prin

Quickstart: Acquire a token and call Microsoft Graph from a Java daemon app

Prerequisites

Register and download your quickstart app

Step 1: Register the application

Step 2: Download the Java project

Step 3: Configure the Java project

Global tenant administrator

Standard user

Step 5: Run the application

More information

MSAL Java

MSAL initialization

Requesting tokens

Help and support

Next steps

Feedback

Resurse suplimentare

Partajați prin

Quickstart: Acquire a token and call Microsoft Graph from a Java daemon app

Prerequisites

Register and download your quickstart app

Step 1: Register the application

Step 2: Download the Java project

Step 3: Configure the Java project

Step 4: Admin consent

Global tenant administrator

Standard user

Step 5: Run the application

More information

MSAL Java

MSAL initialization

Requesting tokens

Help and support

Next steps

Feedback

Resurse suplimentare