I am not able to upload the drawing file and not able to open file in forge viewer.

I am using two legged authentication api. Please find code snippet below.

$twoLeggedAuth = new TwoLeggedAuth();
$twoLeggedAuth->setScopes( [ 'bucket:read' ,'data:read','data:write' ] );
$twoLeggedAuth->fetchToken();

For token genration i am using two legged authentication method

How can I change above code with new one.