$clientid = "XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX"
$clientsecret = "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
$subscriptionid = "XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX"
$tenantid = "XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX"
$resource = "https://management.azure.com/"
$tokenendpoint = "https://login.microsoftonline.com/$tenantid/oauth2/token"
$body = @{
    grant_type    = "client_credentials"
    resource      = $resource
    client_id     = $clientid
    client_secret = $clientsecret
}
$tokenresponse = Invoke-RestMethod -Method Post -Uri $tokenendpoint -Body $body -ContentType "application/x-www-form-urlencoded"
$accesstoken = $tokenresponse.access_token