Is it possible to configure email alert at specific days and specific time in Riemann?

Question

I am using Riemann in my project to trigger an email alert. Is it possible to trigger email alert only for specific days lets say(mon-fri @ 3am to 8pm) only.

If so can anyone help me with the reference.

My updated code:

(tcp-server {:host "127.0.0.1" :port 5555})

(let [userindex1 (default :ttl 300 (update-index (index)))])  
  (let [email (mailer {....email configuration})]
            (streams
        (where (service "log")
            (smap
              (fn [events]
               (let [count-of-transaction (count (filter #(= "error" (:type %)) events))]
                  (event
                  {
                     :status "Failure"
                     :metric  count-of-failures 
                     :total-fail (< count-of-failures 2)})))

              (where (let [now (clj-time.core/now)]
                    (and (<= 3 (clj-time.core/hour now) 20)
                         (<= 1 (clj-time.core/day-of-week now) 5)
                         (= (:status event) "Failure")
                         (:total-fail event)))
                (rollup 1 200
                (email "xxx@xx.com")
                 ))prn))))

Answer 1

Yes! you can put any code you want into the conditional positon of a where clause here is an example config that depends on the time of day and day of week to decide when to send "alerts":

; -*- mode: clojure; -*-
>; vim: filetype=clojure

(riemann.repl/start-server! {:port 5557 :host "0.0.0.0"}) ;; this is only safe in a docker container


; Listen on the local interface over TCP (5555), UDP (5555), and websockets
; (5556)
(let [host "0.0.0.0"]
  (tcp-server {:host host})
  (ws-server  {:host host}))

; Expire old events from the index every 5 seconds.
(periodically-expire 5)

(require '[clj-time [core :refer [now hour day-of-week]]])

(let [index (tap :index (index))]
  (streams
   (where (service "log")
          (fixed-event-window 3
                             (smap
                              (fn [events]
                                (let [count-of-failures (count (filter #(= "error" (:type %)) events))
                                      new-event (assoc (first events)
                                                       :status "Failure"
                                                       :metric  count-of-failures
                                                       :ttl 300
                                                       :total-fail (> count-of-failures 2))]                                      
                                  new-event))
                              (where (fn [event]
                                       (let [now (clj-time.core/now)]
                                         (and (<= 0 (clj-time.core/hour now) 17)
                                              (<= 2 (clj-time.core/day-of-week now) 6)
                                              (= (:status event) "Failure")
                                              (:total-fail event))))
                                     (throttle 1 200
                                               #(println "emailing about" %)
                                               index)))))))

(tests
  (deftest index-test
    (let [workday (clj-time.format/parse "2142-01-01T00:00:00.000Z")
          weekend (clj-time.format/parse "2142-01-03T00:00:00.000Z")]
      (let [index-after-events (with-redefs [clj-time.core/now (constantly workday)]
                                 (inject! [{:service "log"
                                            :type    "error"
                                            :time    42}
                                           {:service "log"
                                            :type    "error"
                                            :time    43}
                                           {:service "log"
                                            :type    "error"
                                            :time    44}]))]
        (is (= index-after-events
               {:index [{:service "log", :type "error", :time 42, :status "Failure", :metric 3, :ttl 300, :total-fail true}]})))
      (let [index-after-events (with-redefs [clj-time.core/now (constantly weekend)]
                                 (inject! [{:service "log"
                                            :type    "error"
                                            :time    42}
                                           {:service "log"
                                            :type    "error"
                                            :time    43}
                                           {:service "log"
                                            :type    "error"
                                            :time    44}]))]
        (is (= index-after-events
               {:index []}))))))

and run the tests:

root@176ee53d0c62:/test# riemann test sample.config
INFO [2016-10-03 22:07:39,805] main - riemann.bin - Loading /test/sample.config
INFO [2016-10-03 22:07:39,840] main - riemann.repl - REPL server {:port 5557, :host 0.0.0.0} online

Testing riemann.config-test
emailing about {:service log, :type error, :time 42, :status Failure, :metric 3, :ttl 300, :total-fail true}

Ran 1 tests containing 2 assertions.
0 failures, 0 errors.

In this example I used fixed-event-window because I couldn't figure out how to make fixed-time-window work in a unit test in riemann. I think it's taken long enough to figure that out that I thought you would be interested in seeing the solution thus far. If you change it to a fixed-time-window it will work the same, except the tests won't run.