Simple Example IRC Bot, my first clojure program!

gistfile1.clj

(ns cljbot
  (:use [clojure.string :only (split join)]
        [clojure.pprint :only (pprint)])
  (:import (javax.net.ssl SSLSocketFactory X509TrustManager SSLContext TrustManager)
           (java.io BufferedReader PrintWriter InputStreamReader)
           (java.security SecureRandom)
           (java.util.regex Pattern)))

(def HOST "irc.teranetworks.de")
(def PORT 6697)
(def CHANNEL "#test")
(def IDENT 
  {:nick "conjurer"
   :username "cljbot"
   :realname "Clojure"}
)
(def PREFIX "!")

(defn trust-invalid-manager []
  "This allows the ssl socket to connect with invalid/self-signed SSL certs."
  (reify X509TrustManager
    (getAcceptedIssuers [this] nil)
    (checkClientTrusted [this certs authType])
    (checkServerTrusted [this certs authType])
  )
)

(defn get-irc-conn [host port]
  "Connects to host and port and returns input and output streams."
  (def ssl-context (SSLContext/getInstance "SSL"))
  (.init ssl-context nil (into-array TrustManager [(trust-invalid-manager)])
         (new SecureRandom))
  (let [socket (.createSocket (.getSocketFactory ssl-context) host port)]
    {:in (new BufferedReader (new InputStreamReader (.getInputStream socket)))
     :out (new PrintWriter (.getOutputStream socket))}
  )
)

(defn parse-raw [line]
  "Parses the messages sent from the server into a descriptive hash map."
  (let [[_ source command args message] (re-matches 
      #"^(?:[:](\S+) )?(\S+)(?: (?!:)(.+?))?(?: [:](.+))?$" line)]
    {:source source
     :command command
     :args args
     :message message}
  )
)

(defn parse-privmsg [params]
  "Parses privmsg using a simple command syntax, similar to other irc bots."
  (def pattern (re-pattern (str "^(" (Pattern/quote PREFIX) "|" 
    (Pattern/quote (:nick IDENT)) "[:|,] ?)?([^ ]+) ?(.*)?$"))
  )
  (if-let [[_ prefix action args] (re-matches pattern (:message params))]
    (if (or prefix (and (not prefix) (.equals (:args params) (:nick IDENT))))
      {:prefix prefix :action action :args (split args #" ")}
    )
  )
)

(defn action-ping [sendline reply args params]
  (reply "pong")
)

(defn action-version [sendline reply args params]
  (reply "clojure irc bot!")
)

(defn action-quit [sendline reply args params]
  (sendline (str "QUIT :" (join " " args)))
)

(defn handle-privmsg [params sendline]
  (defn reply [message]
    (if (= (.indexOf (:args params) "#") 0)
      (def dest (:args params))
      (def dest (:source params))
    )
    (sendline (str "PRIVMSG " dest " :" message))
  )
  (if-let [{action :action args :args} (parse-privmsg params)]
    (let [fnk (ns-resolve 'cljbot (symbol (str "action-" action)))]
      (if fnk (fnk sendline reply args params))
    )
  )
)

(defn handle-raw [params sendline]
  (when (.equals (:command params) "PING")
    (sendline (str "PONG :" (:message params)))
  )
  (when (.equals (:command params) "376")
    (sendline (str "JOIN " CHANNEL))
  )
  (when (.equals (:command params) "PRIVMSG")
    (handle-privmsg params sendline)
  )
)

(defn mainloop [in sendline]
  (doseq [line (line-seq in)]
    (handle-raw (parse-raw line) sendline)
  )
)

(defn -main [& args]
  (let [{in :in out :out} (get-irc-conn HOST PORT)]
    (defn sendline [line]
      "Sends a single line to the irc server."
      (println "<" line)
      (doto out
        (.print (str line "\r\n"))
        (.flush)
      )
    )

    (println "bot connected, sending nick/user...")
    (sendline (str "NICK " (:nick IDENT)))
    (sendline (str "USER " (:username IDENT) " 0 * :" (:realname IDENT)))

    (mainloop in sendline)
  )
)