import http.server, socketserver, socket
class H(http.server.SimpleHTTPRequestHandler):
    def log_message(self, fmt, *a):
        import sys, datetime
        sys.stderr.write(datetime.datetime.utcnow().isoformat()+'Z '+ (fmt%a) +'\n')
        open('/tmp/ssrflog80/httpd.log','ab').write((datetime.datetime.utcnow().isoformat()+'Z '+(fmt%a)+'\n').encode())
class S(socketserver.ThreadingTCPServer):
    address_family = socket.AF_INET6
    allow_reuse_address = True
    def server_bind(self):
        try: self.socket.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_V6ONLY, 0)
        except Exception: pass
        super().server_bind()
import os
os.chdir('/tmp/ssrflog80')
srv = S(('::', 80), H)
srv.serve_forever()