Get access without a user

• 9/20/2019
• 9 minutes to read
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Some apps call Microsoft Graph with their own identity and not on behalf of a user. In many cases, these are background services or daemons that run on a server without the presence of a signed-in user. An example of such an app might be an email archival service that wakes up and runs overnight. In some cases, apps that have a signed-in user present may also need to call Microsoft Graph under their own identity. For example, an app may need to use functionality that requires more elevated privileges in an organization than those carried by the signed-in user.

Apps that call Microsoft Graph with their own identity use the OAuth 2.0 client credentials grant flow to get access tokens from Azure AD. This topic describes the basic steps to configure a service and use the OAuth client credentials grant flow to get an access token.

Authentication and authorization steps

The basic steps required to configure a service and get a token from the Microsoft identity platform endpoint that your service can use to call Microsoft Graph under its own identity are:

1. Register your app.
2. Configure permissions for Microsoft Graph on your app.
3. Get administrator consent.
4. Get an access token.
5. Use the access token to call Microsoft Graph.

1. Register your app

To authenticate with the Microsoft identity platform endpoint, you must first register your app at the Azure app registration portal. You can use either a Microsoft account or a work or school account to register your app.

For a service that will call Microsoft Graph under its own identity, you need to register your app for the Web platform and copy the following values:

• The Application ID assigned by the Azure app registration portal.
• A Client (application) Secret, either a password or a public/private key pair (certificate).
• A Redirect URL for your service to receive token responses.
• A Redirect URL for your service to receive admin consent responses if your app implements functionality to request administrator consent.

For steps on how to configure an app using the Azure app registration portal, see Register your app.

With the OAuth 2.0 client credentials grant flow, your app authenticates directly at the Microsoft identity platform /token endpoint using the Application ID assigned by Azure AD and the Application Secret that you create using the portal.

2. Configure permissions for Microsoft Graph

For apps that call Microsoft Graph under their own identity, Microsoft Graph exposes application permissions (Microsoft Graph can also expose delegated permissions for apps that call Microsoft Graph on behalf of a user). You pre-configure the application permissions your app needs when you register your app. Application permissions always require administrator consent. An administrator can either consent to these permissions using the Azure portal when your app is installed in their organization, or you can provide a sign-up experience in your app through which administrators can consent to the permissions you configured. Once administrator consent is recorded by Azure AD, your app can request tokens without having to request consent again. For more detailed information about the permissions available with Microsoft Graph, see the Permissions reference

To configure application permissions for your app in the Azure app registrations portal: under an application's API permissions page, choose Add a permission, select Microsoft Graph, and then choose the permissions your app requires under Application permissions.

The following screenshot shows the Select Permissions dialog box for Microsoft Graph application permissions.

Note: We recommend that you configure the least privileged set of permissions required by your app. This provides a much more comfortable experience for administrators than having to consent to a long list of permissions.

3. Get administrator consent

You can rely on an administrator to grant the permissions your app needs at the Azure portal; however, often, a better option is to provide a sign-up experience for administrators by using the Microsoft identity platform /adminconsent endpoint.

Important: Any time you make a change to the configured permissions, you must also repeat the Admin Consent process. Changes made in the app registration portal will not be reflected until consent has been reapplied by the tenant's administrator.

Request

// Line breaks are for legibility only.

GET https://login.microsoftonline.com/{tenant}/adminconsent
?client_id=6731de76-14a6-49ae-97bc-6eba6914391e
&state=12345
&redirect_uri=https://localhost/myapp/permissions

Administrator consent experience

With requests to the /adminconsent endpoint, Azure AD enforces that only a tenant administrator can sign in to complete the request. The administrator will be asked to approve all the application permissions that you have requested for your app in the app registration portal.

The following is an example of the consent dialog that Azure AD presents to the administrator:

Response

If the administrator approves the permissions for your application, the successful response looks like this:

// Line breaks are for legibility only.

GET https://localhost/myapp/permissions
?tenant=a8990e1f-ff32-408a-9f8e-78d3b9139b95&state=12345
&admin_consent=True

Try: You can try this for yourself by pasting the following request in a browser. If you sign in as a Global administrator for an Azure AD tenant, you will be presented with the administrator consent dialog box for the app. (This will be a different app than that in the consent dialog box screenshot shown earlier.)

https://login.microsoftonline.com/common/adminconsent?client_id=6731de76-14a6-49ae-97bc-6eba6914391e&state=12345&redirect_uri=https://localhost/myapp/permissions

4. Get an access token

In the OAuth 2.0 client credentials grant flow, you use the Application ID and Application Secret values that you saved when you registered your app to request an access token directly from the Microsoft identity platform /token endpoint.

You specify the pre-configured permissions by passing https://graph.microsoft.com/.default as the value for the scope parameter in the token request. See the scope parameter description in the token request below for details.

Token request

You send a POST request to the /token identity platform endpoint to acquire an access token:

// Line breaks are for legibility only.

POST https://login.microsoftonline.com/{tenant}/oauth2/v2.0/token HTTP/1.1
Host: login.microsoftonline.com
Content-Type: application/x-www-form-urlencoded

client_id=535fb089-9ff3-47b6-9bfb-4f1264799865
&scope=https%3A%2F%2Fgraph.microsoft.com%2F.default
&client_secret=qWgdYAmab0YSkuL1qKv5bPX
&grant_type=client_credentials

Token response

A successful response looks like this:

{
  "token_type": "Bearer",
  "expires_in": 3599,
  "access_token": "eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiIsIng1dCI6Ik1uQ19WWmNBVGZNNXBP..."
}

5. Use the access token to call Microsoft Graph

After you have an access token, you can use it to call Microsoft Graph by including it in the Authorization header of a request. The following request gets the profile of a specific user. Your app must have the User.Read.All permission to call this API.

GET https://graph.microsoft.com/v1.0/users/12345678-73a6-4952-a53a-e9916737ff7f
Authorization: Bearer eyJ0eXAiO ... 0X2tnSQLEANnSPHY0gKcgw
Host: graph.microsoft.com

A successful response will look similar to this (some response headers have been removed):

HTTP/1.1 200 OK
Content-Type: application/json;odata.metadata=minimal;odata.streaming=true;IEEE754Compatible=false;charset=utf-8
request-id: f45d08c0-6901-473a-90f5-7867287de97f
client-request-id: f45d08c0-6901-473a-90f5-7867287de97f
OData-Version: 4.0
Duration: 309.0273
Date: Wed, 26 Apr 2017 19:53:49 GMT
Content-Length: 407

{
    "@odata.context":"https://graph.microsoft.com/v1.0/$metadata#users/$entity",
    "id":"12345678-73a6-4952-a53a-e9916737ff7f",
    "businessPhones":[
        "+1 555555555"
    ],
    "displayName":"Chris Green",
    "givenName":"Chris",
    "jobTitle":"Software Engineer",
    "mail":null,
    "mobilePhone":"+1 5555555555",
    "officeLocation":"Seattle Office",
    "preferredLanguage":null,
    "surname":"Green",
    "userPrincipalName":"ChrisG@contoso.onmicrosoft.com"
}

Supported app scenarios and resources

Apps that call Microsoft Graph under their own identity fall into one of two categories:

• Background services (daemons) that run on a server without a signed-in user.
• Apps that have a signed-in user but also call Microsoft Graph with their own identity; for example, to use functionality that requires more elevated privileges than those of the user.

Apps that call Microsoft Graph with their own identity use the OAuth 2.0 client credentials grant to authenticate with Azure AD and get a token. For the Microsoft identity platform endpoint, you can explore this scenario further with the following resources:

• For a more complete treatment of the client credentials grant flow that also includes error responses, see Azure Active Directory v2.0 and the OAuth 2.0 client credentials flow.
• For a sample that calls Microsoft Graph from a service, see the v2.0 daemon sample on GitHub.
• For more information about recommended Microsoft and third-party authentication libraries, see Microsoft identity platform authentication libraries.

Endpoint considerations

Microsoft continues to support the Azure AD endpoint. There are several differences between using the Microsoft identity platform endpoint and the Azure AD endpoint. When using the Azure AD endpoint:

• If your app is a multi-tenant app, you must explicitly configure it to be multi-tenant in the Azure portal.
• There is no admin consent endpoint (/adminconsent). Instead, your app can request administrator consent during runtime by adding the prompt=admin_consent parameter to an authorization request. For more information, see Triggering the Azure AD consent framework at runtime in Integrating applications with Azure Active Directory.
• The parameters in authorization and token requests are different. For example, there is no scope parameter in Azure AD endpoint requests; instead, the resource parameter is used to specify the URI of the resource (resource=https://graph.microsoft.com) that authorization (for administrator consent) or a token is being requested for.

You can explore this scenario further with the following resources:

• For information about using the Microsoft identity platform with different kinds of apps, see the Get Started links in the Microsoft identity platform documentation. The guide contains links to overview topics, quickstarts, tutorials, code samples, and protocol documentation for different kinds of apps supported by the Microsoft identity platform.
• For information about the Microsoft Authentication Library (MSAL) and server middleware available for use with the Microsoft identity platform endpoint, see Microsoft Authentication Libraries.