3 part redirect irule query. non www to www to https

If you always want to redirect from HTTP to HTTPS I would recommend using a 301 (permanent redirect) as opposed to the 302 (temporary redirect) that is generated by

HTTP::redirect

You accomplish this by replacing

HTTP::redirect "https://www.sharepointsite.com[HTTP::uri]"

HTTP::respond 301 Location "https://www.sharepointsite.com[HTTP::uri]"

You can further optimize by using HSTS, which instructs clients to use HTTPS for subsequent requests even if the link specifies HTTP.