Polling endpoint with core.async

polling.clj

(ns clojure.polling
  (:require [clj-http.client :as client]
            [clojure.core.async :as async :refer [>!! timeout <! go-loop]]
            [cheshire.core :as json]
            [clojure.tools.logging :as log]))
            
(defn client
  ([endpoint]
   (client/get endpoint))
  ([endpoint c e]
   (client/get endpoint {:async true}
               (fn [response] (>!! c (:body response)))
               (fn [exception] (>!! e (.getMessage exception))))))

(defn poll [endpoint c e]
  (go-loop []
    (client endpoint c e)
    (<! (timeout 1000))
    (recur)))

(defn read-data [c]
  (go-loop []
    (let [s (<! c)]
      (if (empty? s)
        (recur)
        (let [data (json/parse-string s true)]
            (log/info data)
            (recur))))))
  
(defn read-errors [e]
  (go-loop []
    (let [error (<! e)]
      (log/fatal error)
      (recur))))

(defn polling [endpoint]
  (let [c (async/chan)
        e (async/chan)]
    (read-data c)
    (read-errors e)
    (poll endpoint c e)))