post_install() {
  groupadd logstash &>/dev/null
  useradd -g logstash -d /opt/logstash -s /bin/false -r logstash &>/dev/null

  chown -R logstash:logstash opt/logstash var/lib/logstash
}

post_upgrade() {
  getent group logstash >/dev/null 2>&1 || groupadd logstash &>/dev/null
  getent passwd logstash >/dev/null 2>&1 || useradd -g logstash -d /opt/logstash -s /bin/false -r logstash &>/dev/null

  chown -R logstash:logstash opt/logstash
}