A much better version of a URL shortening service in VCL. It now uses libvmod-redis and works similar to the ugly Inline C VCL.

default.vcl

import redis;

sub vcl_recv {
    if (req.url ~ "^/[lL]/[A-Za-z0-9\-_]{4,32}=?=?$") {
        set req.http.New-Location = redis.call(regsub(req.url, "^/[lL]/([A-Za-z0-9\-_]{2})([A-Za-z0-9\-_]{2,30}=?=?)$", "HGET short:\1 \2"));
        if (req.http.New-Location) {
            error 666;
        }
        error 404 "Not Found";
    }
}

sub vcl_error {
    if (obj.status == 666) {
        set obj.http.Location = req.http.New-Location;
        unset req.http.New-Location;
        set obj.status = 302;
        set obj.response = "Found";
        set obj.ttl = 120s;
        return (deliver);
    }
}