Rewriting of headers

Because we are based on Varnish Enterprise software, Transparent Edge offers great flexibility when it comes to changing your website’s default behavior.

Rewriting headers is very common and rather easy to do. The most typical cases are:

Rewriting the Host header

The typical use case:

sub vcl_recv{
  if ((req.http.host == "www.transparentcdn.com") && (bereq.url ~ "/blog")) {
    set http.host == "blog.transparentcdn.com"
    set req.backend_hint = c83_tcdn.backend();
  }
}

Rewriting the Cache-Control header

sub vcl_backend_response {
     if ((bereq.http.host == "www.transparentcdn.com") && (bereq.url ~ "/my-new-url")) {
            set beresp.http.Cache-Control = "max-age=0, s-maxage=10";
            set beresp.ttl = 10s;
    }
}

Deleting headers

Based on the previous example, we can erase the Cache-Control header that comes from the origin before forcing the cache time.

sub vcl_backend_response {    
    if ((bereq.http.host == "www.transparent.com") && (bereq.url ~ "/my-new-url")) {
            unset beresp.http.Cache-Control;
            set beresp.http.Cache-Control = "max-age=0, s-maxage=10";
            set beresp.ttl = 10s;
    }
}