Custom Attributes Mapping for Microsoft Entra

Pre-requisites

Make sure you have the following privileges:

• Microsoft Entra Admin Center login requires you to be at least a User Administrator | Microsoft. 
• Graph API consent permission.
• Microsoft Azure Portal login.

Option 1 - Using Microsoft Entra Admin Center

1. Sign in to the Microsoft Entra Admin Center, https://entra.microsoft.com/.
2. From the menu, navigate to Identity > External Identities > Overview.
3. From the sub-menu, select Custom user attributes and the available user attributes are listed.

You can add the custom attribute here.

4. Click the +Add button and the Add an attribute form displays.

5. In the Name field, enter the name for the custom attribute.
6. From the Data Type drop-down, select a data type, such as String, Boolean, or Integer.
7. In the the Description field, enter a short description of the custom attribute. This is for internal use and isn't visible to the user.
8. Click the Create button.

Option 2 - Using Graph API

You can add an attribute and update custom attribute to the user from Graph API. 

1. Navigate to Graph Explorer | Microsoft Graph APIs, https://developer.microsoft.com/en-us/graph/graph-explorer
2. Click the API Explorer to displays the available resources.

3. From the Resources Available navigate to applications>{application-id}>extensionProperties
4. Click POST.

{
    "name": "{name of attribute}",
    "dataType": "{data type of attribute}",
    "targetObjects": [
        "User"
    ]
}

The custom attribute created above is now updated for a particular user. 

1. Navigate to the Sample Queries tab.
2. Select Users > PATCH (update user) API.
3. Update the value by running the above API.

The {id} used in the patch request URL can fetched: 

1. Navigate to the Azure Portal.
2. Select Microsoft Entra ID resource. 
3. From the menu, navigate to Manage > Users.
4. Select the User.
5. In the Overview copy the Object ID / User principal name.

API Request Body

{
    "{name of attribute}": "{value}"
}