varnish-caching-suggestion.txt

gistfile1.txt

vcl 4.0;

...

sub vcl_recv {

...

    # Protecting against the HTTPOXY CGI vulnerability.
    unset req.http.proxy;
    
    # Remove the Google Analytics added parameters.
    if (req.url ~ "(\?|&)(utm_source|utm_medium|utm_campaign|utm_content|gclid|cx|ie|cof|siteurl)=") {
        set req.url = regsuball(req.url, "&(utm_source|utm_medium|utm_campaign|utm_content|gclid|cx|ie|cof|siteurl)=([A-z0-9_\-\.%25]+)", "");
        set req.url = regsuball(req.url, "\?(utm_source|utm_medium|utm_campaign|utm_content|gclid|cx|ie|cof|siteurl)=([A-z0-9_\-\.%25]+)", "?");
        set req.url = regsub(req.url, "\?&", "?");
        set req.url = regsub(req.url, "\?$", "");
    }
    
    # Strip hash, server doesn't need it.
    if (req.url ~ "\#") {
        set req.url = regsub(req.url, "\#.*$", "");
    }

    # Strip a trailing ? if it exists
    if (req.url ~ "\?$") {
        set req.url = regsub(req.url, "\?$", "");
    }
    
    # Normalize the query arguments
    set req.url = std.querysort(req.url);

...

}