Functions/Join-AppSettingActiveDirectory.ps1

function Join-AppSettingActiveDirectory{
    $appSettingsCrossReferencedItems = New-Object System.Collections.ArrayList;
    $allWebApps = Get-AzureRmWebApp -ResourceGroupName $resourceGroupName;

    foreach($currentWebApp in $allWebApps){
        $sitename = $currentWebApp.SiteName;
        $siteAppSettingsInfo = Invoke-AzureRmResourceAction -ResourceGroupName $resourceGroupName -ResourceType Microsoft.Web/sites/Config -Name $sitename/appsettings -Action list -ApiVersion 2015-08-01 -Force
        $siteAppSettings = $siteAppSettingsInfo.Properties

        foreach($appSetting in $siteAppSettings.PSObject.Properties){
            foreach($activeDirectoryApplication in $scannedADApplications){
                if($activeDirectoryApplication.ApplicationId.ToString() -eq $appSetting.Value){
                    $referencedApplication = New-Object PSObject;
                    $referencedApplication | add-member -MemberType NoteProperty -Name "SiteName" -Value $sitename;
                    $referencedApplication | add-member -MemberType NoteProperty -Name "SiteURL" -Value $currentWebApp.DefaultHostName;
                    $referencedApplication | add-member -MemberType NoteProperty -Name "SiteResourceGroup" -Value $resourceGroupName;
                    $referencedApplication | add-member -MemberType NoteProperty -Name "SiteConfigKey" -Value $appSetting.Name;
                    $referencedApplication | add-member -MemberType NoteProperty -Name "ActiveDirectory_AppID" -Value $activeDirectoryApplication.ApplicationId;
                    $referencedApplication | add-member -MemberType NoteProperty -Name "ActiveDirectory_DisplayName" -Value $activeDirectoryApplication.DisplayName;
                    $referencedApplication | add-member -MemberType NoteProperty -Name "ActiveDirectory_StartDate" -Value $activeDirectoryApplication.StartDate;
                    $referencedApplication | add-member -MemberType NoteProperty -Name "ActiveDirectory_EndDate" -Value $activeDirectoryApplication.EndDate;

                    $appSettingsCrossReferencedItems.Add($referencedApplication) | Out-Null;
                }
            }
        }
    }
    if($appSettingsCrossReferencedItems){
        Set-Output -outputData $appSettingsCrossReferencedItems -outputFileName "AppService_ActiveDirectory";
    }
}