To grant permissions to a SharePoint Online site for an Azure Managed Identity, you'll need to create an Azure AD App Registration for your Managed Identity and grant the necessary permissions to that app in SharePoint Online
- Create an App Registration in Azure AD
- Azure Active Directory > App registrations
- New registration > Note the "Application (client) ID" and "Directory (tenant) ID" values
- Assign the necessary permissions to the App Registration in SharePoint Online
- SharePoint Online site. > Site permissions > Advanced permissions settings
- Grant permissions > Select Users > client_id@tenant_id
- Configure your Azure service to use the App Registration
- In your Azure service, update the configuration to use the App Registration's "Application (client) ID" and "Directory (tenant) ID" for authentication with SharePoint Online.
- Use the SharePoint Online REST API or the Microsoft Graph API to access SharePoint Online resources, authenticating with the App Registration's credentials.