Varnish String Concatenation in VCL
For whatever reason, I have not seen Varnish documentation on concatenating strings. It's not on the official operators list. Even more bothersome, I occasionally see people using regular expression substitutions (
regsuball) to do string concatenation in Varnish's VCL.
In fact, string concatenation in Varnish is simply a matter of setting a variable with two strings. For example, here's how to prefix a URL in
set req.url = "/my_prefix" req.url
That's actually all there is to it. No explicit operator is needed. <!--break-->