To force a browser to use HTTPS instead of HTTP, a policy needs to be in place so that the proxy can send an HTTP-302 message (redirect) to the browser.
The policy will maintain any path that was first provided with the original request. You need to install the CPL code in the local policy file on the ProxySG
For example, if you need to force clients to use https when accessing www.facebook.com, then the required policy would be as follows:
;;;;;;;;start of the policy
ALLOW url.scheme=http url.host=www.facebook.com action.Redirect_to_HTTPS_example(yes)
;;;;;;;end of the policy