Merge pull request #11 from emlyn/master

Add IRC Appender (thanks to emlyn)

README.md

@@ -152,6 +152,32 @@ And make sure emails are sent asynchronously:
 (timbre/set-config! [:appenders :postal :async?] true)
 ```
 
+### IRC Appender
+
+To enable the standard [irclj](https://github.com/flatland/irclj)-based IRC appender, add the irclj dependency to your `project.clj`:
+
+```clojure
+[irclj "0.5.0-alpha2"]
+```
+
+And add the appender to your `ns` declaration:
+
+```clojure
+(:require [taoensso.timbre.appenders.irc :refer [irc-appender]])
+```
+
+Then adjust your Timbre config:
+
+```clojure
+(timbre/set-config! [:appenders :irc] irc-appender)
+(timbre/set-config! [:shared-appender-config :irc]
+                    {:host "irc.example.org"
+                     :port 6667
+                     :nick "logger"
+                     :name "Logger"
+                     :chan "#logs"})
+```
+
 ### Custom Appenders
 
 Writing a custom appender is dead-easy:

src/taoensso/timbre/appenders/irc.clj

@@ -0,0 +1,47 @@
+(ns taoensso.timbre.appenders.irc
+  "IRC appender for irclj.
+  Ref: https://github.com/flatland/irclj."
+  {:author "Emlyn Corrin"}
+  (:require [clojure.string  :as str]
+            [irclj.core      :as irclj]
+            [taoensso.timbre :as timbre]))
+
+(def conn (atom nil))
+
+(defn connect [{:keys [host port pass nick user name chan]
+                :or {:port 6667}}]
+  (let [conn (irclj/connect host port nick
+                            :username  user
+                            :real-name name
+                            :pass      pass
+                            :callbacks {})]
+    (irclj/join conn chan)
+    conn))
+
+(defn ensure-conn [conf]
+  (swap! conn #(or % (connect conf))))
+
+(defn send-message [{:keys [message prefix chan] :as config}]
+  (let [conn (ensure-conn config)
+        lines (str/split message #"\n")]
+    (irclj/message conn chan prefix (first lines))
+    (doseq [line (rest lines)]
+      (irclj/message conn chan ">" line))))
+
+(defn appender-fn [{:keys [ap-config prefix message]}]
+  (when-let [irc-config (:irc ap-config)]
+    (send-message
+     (assoc irc-config
+       :prefix (if-let [prefix-fn (:prefix-fn irc-config)]
+                 (prefix-fn prefix)
+                 prefix)
+       :message message))))
+
+(def irc-appender
+  {:doc (str "Sends IRC messages using irclj.\n"
+             "Needs :irc config map in :shared-appender-config, e.g.:
+             {:host \"irc.example.org\" :port 6667 :nick \"logger\"
+              :name \"My Logger\" :chan \"#logs\"")
+   :min-level :info :enabled? true :async? false
+   :max-message-per-msecs nil ; no rate limit by default
+   :fn appender-fn})