gistfile1.clj

  (streams

    ; Index all events immediately.
    ; index
    (where (service "http")
        (where (not (expired? event))
          (where (state "200")
            (by :host
              (runs 3 :state
                index
                prn))
            (else
              (with :state "critical"
                (by :host
                  (runs 3 :state
                    index
                    prn)))))))
    ; Calculate an overall rate of events.
    (with {:metric 1 :host nil :state "ok" :service "events/sec"}
      (rate 5 index))

    ; Log expired events.
    (expired
      (fn [event] (info "expired" event))))))