=== topic exchange ===
routing key              orders.eu    orders.high  note
order.eu.high            true         true         matches both
order.eu.low             true         false        matches order.eu.* only
order.us.high            false        true         matches order.#.high only
order.eu.west.high       false        true         matches order.#.high only - * is one word
order.high               false        true         matches order.#.high - # can be zero words