start, stop, error, clojure, core.async

start-kill-error.clj

(ns cmp.system
  ^{:author "wactbprot"
    :doc "study."}
  (:require [taoensso.timbre :as timbre]
            [clojure.core.async :as a]))
;;------------------------------
;; kill channel 
;;------------------------------
(def kill> (a/chan))

;;------------------------------
;; error channel 
;;------------------------------
(def err< (a/chan))

(defn error-handler
  [err<]
  (a/go-loop []
    (let [e (a/<! err<)]
    (if (string? e)
      (timbre/error e)
      (timbre/error (.getMessage e))))
    (recur)))

(defn launch
  [in> dispatch-fn kill> err<]
  (a/go-loop [coll (a/alts! [kill> in>] :priority true)]
    (let [[x ch] coll]
      (if (= ch kill>)
        (timbre/warn "receive msg in kill> channel; shutdown")
        (do
          (try
            (dispatch-fn x)
            (catch Exception e
              (a/>! err< e)))
          (recur (a/alts! [kill> in>] :priority true)))))))