gistfile1.clj

; Expire old events from the index every 15 seconds.
(periodically-expire 10 {:keep-keys [:host :service :tags]})

(def rollup-ttl 60)
(def throttle-ttl 120)

(defn event-log [prefix]
  (fn [e] (info prefix (str e))))

(def email (mailer {:from "riemann@domain"}))
(def page-email (mailer {:from "pager@domain"}))

(def pd (pagerduty "KEYYYY"))
(def pager (where (state "ok") (:resolve pd) (else (:trigger pd))))

; Keep events in the index for 5 minutes by default.
(let [index (default :ttl 300 (update-index (index)))]

  ; Inbound events will be passed to these streams:
  (streams

    ; Index all events immediately.
    index

    (changed-state {:init "ok"}
      (where (not (expired? event))
        ; Send all events via email
        (tagged-any ["notify" "page" "pager"]
          (rollup 1 rollup-ttl (email "brian@domain")))

        ; Send paging events via pager as well
        (tagged-any ["page" "pager"]
          (where (not (state "warn")) pager))))

    ; Handle expired events separately
    (by :host
      (where (expired? event)
        ; Send all events via email
        (tagged-any ["notify" "page" "pager"]
          (rollup 1 rollup-ttl (event-log "rollup-expired"))) ; works

        ; Send paging events via pager as well
        (tagged-any ["page" "pager"]
          (throttle 1 10 (event-log "throttle-expired"))) ; does nothing
      (else (throttle 1 10 (event-log "throttle-unexpired"))))) ; logs riemann.codec.Event@24ecd819
))