Add socket appender

README.md

@@ -154,6 +154,18 @@ Filter logging output by namespaces:
                      :chan "#logs"})
 ```
 
+#### Socket ([server-socket](https://github.com/technomancy/server-socket)) appender
+
+```clojure
+;; [server-socket "1.0.0"] ; Add to project.clj dependencies
+;; (:require [taoensso.timbre.appenders (socket :as socket-appender)]) ; Add to ns
+
+(timbre/set-config! [:appenders :socket] socket-appender/socket-appender)
+(timbre/set-config! [:shared-appender-config :socket]
+                    {:list-addr "127.0.0.1"
+                     :port 9000})
+```
+
 ### Custom appenders
 
 Writing a custom appender is dead-easy:

src/taoensso/timbre/appenders/socket.clj

@@ -0,0 +1,40 @@
+(ns taoensso.timbre.appenders.socket
+  "TCP Socket appender. Depends on https://github.com/technomancy/server-socket."
+  {:author "Emlyn Corrin"}
+  (:require [server.socket :refer [create-server]])
+  (:import [java.net Socket InetAddress]
+           [java.io BufferedReader InputStreamReader PrintWriter]))
+
+(def conn (atom nil))
+
+(defn listener-fun [in out]
+  (loop [lines (-> in
+                   (InputStreamReader.)
+                   (BufferedReader.)
+                   (line-seq))]
+    (when-not (re-find #"(?i)^quit" (first lines))
+      (recur (rest lines)))))
+
+(defn conect [{:keys [port listen-addr]}]
+  (let [addr (when listen-addr (InetAddress/getByName listen-addr))]
+    (create-server port listener-fun 0 ^InetAddress addr)))
+
+(defn ensure-conn [socket-config]
+  (swap! conn #(or % (connect socket-config))))
+
+(defn appender-fn [{:keys [ap-config prefix message] :as params}]
+  (when-let [socket-config (:socket ap-config)]
+    (let [c (ensure-conn socket-config)]
+      (doseq [sock @(:connections c)]
+        (let [out (PrintWriter. (.getOutputStream ^Socket sock))]
+          (binding [*out* out]
+            (println prefix message)))))))
+
+(def socket-appender
+  {:doc (str "Logs to a listening socket.\n"
+             "Needs :socket config map in :shared-appender-config, e.g.:
+             {:listen-addr nil
+              :port 9000}")
+   :min-level :trace :enabled? true :async? false
+   :max-message-per-msecs nil ; no rate limit by default
+   :fn appender-fn})