pfetch

gistfile1.clj

(ns clj-pfetch.core
  (:use [clojure.java.shell :only (sh)])
  (:require [clojure.xml :as xml]))

;;; Records

(defrecord Url [start href output freq args])

;;; Agents

(def running (agent true))

;;; Methods

(defn- read-file [filename]
  (slurp filename))

(defn- parse-xml [data]
  (-> (.getBytes data "UTF-8")
      input-stream
      xml/parse
      xml-seq))

(defn- make-url [data]
  (let [attrs (:attrs data)
        href (:href attrs)
        output (:output attrs)
        freq (Integer/parseInt (:freq attrs))
        content (:content data)
        path (:path (:attrs (first content)))
        args (map #(first (:content %)) (:content (first content)))]
    (Url. (rand-int 10) href output freq (cons path args))))

(defn- make-urls [x]
  (let [r-urls (:content (first x))]
    (map make-url r-urls)))

(defn exec [args]
  (try
    (apply sh args)
    (catch Exception e
      nil)))

(defn- process-url [url]
  (Thread/sleep (* (:start url) 1000))
  (loop []
    (let [content (slurp (:href url))]
      (spit (:output url) content)
      (exec (:args url))
      (Thread/sleep (* (:freq url) 1000))
      (if @running
        (recur)
        nil))))

(defn process-urls [urls]
  (map #(send (agent %) process-url) urls))

;;; Main

(defn -main [filename]
  (let [content (read-file filename)
        p-xml (parse-xml content)
        urls (make-urls p-xml)]
    (process-urls urls)))