I want to use HTTPS in my site url when it is available and HTTP when it is not.
On our production server we opened a special port in Amazon EC2 for HTTPS secure communication, whereas on my local server I don't have it.
So I want to form a right action automatically without manually changing to http on my local server and back to https on production server in my code.
In other words I want to put a right $action in

<form name="query_form" action=$action method="POST"
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