For Office 365 customers, Holiday Sync Service now supports OAuth authentication. OAuth is a modern and more secure way to authenticate connections.
Before you can set it up to use OAuth for Office 365, you need to follow the steps below on Azure Active Directory.
📌Note: You need to be a tenant admin to do this.
Register your application
Under Manage, click App registrations then click New Registration.
Enter a display name for your application, for example, PeopleHR HolidaySync Service.
Select who can use the application.
Under Redirect URL, select Public client/native (mobile & desktop).
Enter the redirect URL then click Register.
Once you've clicked Register, when the Azure portal displays the app registration overview, copy the Application (client) ID and Directory (tenant) ID, as you need to this to complete the Holiday Sync Service setup.
Configure for app-only authentication
Under Manage, click Manifest.
Locate the requiredResourceAccess property then add the following:
{ "resourceAppId": "00000002-0000-0ff1-ce00-000000000000", "resourceAccess": [ { "id": "dc890d15-9560-4a4c-9b7f-a736ec74ec40", "type": "Role" } ] }Click Save then, under Manage, click API permissions.
Check that full_access_as_app appears on the list.
Click Grant admin consent for org then click Accept.
Under Manage, click Certificates & Secrets.
Click New client secret then enter a description.
Click Add.
Alternatively, you can generate the client secret using PowerShell:
PS> Connect-AzureAD -tenantid your_azure_ad_domain_name
PS> $startDate = Get-Date
PS> $endDate = $startDate.AddYears(99)
PS> New-AzureADApplicationPasswordCredential -ObjectId objectid_from_app_ overview_page -CustomKeyIdentifier "MySecret01" -StartDate $startDate -EndDate $endDate
Once you've done this, copy the value of the newly added client secret and save it, you need this later.
Limit application permissions
By default, OAuth client credentials grant flow allows access to all mailboxes in an organization on Exchange Online. We recommend you limit the application permissions to specific exchange online mailboxes.
Complete the Holiday Sync Service configuration
Open the Holiday Sync Service Config app.
From the Authentication drop-down menu, select OAuth.
Click the Office 365 tab then enter the Application (client) ID, Directory (tenant) ID and Client Secret.
Click Save then, under Windows Services, restart Holiday Sync Service.