Housekeeping for #147

CHANGELOG.md

@@ -1,5 +1,11 @@
 > This project uses [Break Versioning](https://github.com/ptaoussanis/encore/blob/master/BREAK-VERSIONING.md) as of **Aug 16, 2014**.
 
+## Pending
+
+* **New**: added 3rd-party gelf appender [#147 @davewo]
+
+
+
 ## v4.2.1 / 2016 Jan 14
 
 > This is a non-breaking hotfix release

src/taoensso/timbre/appenders/3rd_party/gelf.clj

@@ -1,44 +1,44 @@
 (ns taoensso.timbre.appenders.3rd-party.gelf
-  (:import (org.graylog2.gelfclient
-             GelfConfiguration
-             GelfMessageBuilder
-             GelfTransports
-             GelfMessageLevel)
-           (java.net InetSocketAddress)))
+  "Appender to handle sending messages in the gelf format to a centralized
+  logging server (e.g. Graylog)"
+  {:author "Dave Owens (@davewo)"}
+  (:import
+   [org.graylog2.gelfclient
+    GelfConfiguration
+    GelfMessageBuilder
+    GelfTransports
+    GelfMessageLevel]
+   [java.net InetSocketAddress]))
 
-(defn timbre-to-gelf-level [level]
-  (let [gelf-levels {:info  GelfMessageLevel/INFO
-                     :warn  GelfMessageLevel/WARNING
-                     :error GelfMessageLevel/ERROR
-                     :fatal GelfMessageLevel/CRITICAL}]
+(let [gelf-levels
+      {:info  GelfMessageLevel/INFO
+       :warn  GelfMessageLevel/WARNING
+       :error GelfMessageLevel/ERROR
+       :fatal GelfMessageLevel/CRITICAL}]
+
+  (defn timbre-to-gelf-level [level]
     (get gelf-levels level GelfMessageLevel/WARNING)))
 
 (defn make-gelf-transport
-  "Make a new GelfTransport object, capable of sending a GelfMessage to a remote server.
-
-  Parameters:
-  *`host` - An IP address or hostname string of the remote logging server.
-  *`port` - The TCP or UDP port on which the server listens.
-  *`protocol` - Use :tcp or :udp transport to send messages.
-
-  Returns a new GelfTransport object."
+  "Returns a new GelfTransport object, capable of sending a GelfMessage to a
+  remote server. Params:
+    `host`     - IP address or hostname string of the remote logging server
+    `port`     - TCP or UDP port on which the server listens
+    `protocol` - e/o #{:tcp :udp}"
   [host port protocol]
-  {:pre [(or (= :udp protocol) (= :tcp protocol))]}
+  {:pre [(#{:udp :tcp} protocol)]}
   (let [protocols {:udp GelfTransports/UDP :tcp GelfTransports/TCP}
         transport (protocol protocols)
-        config (-> (GelfConfiguration. (InetSocketAddress. host port)) (.transport transport))]
+        config    (-> (GelfConfiguration. (InetSocketAddress. host port))
+                      (.transport transport))]
     (GelfTransports/create config)))
 
 (defn gelf-appender
-  "A timbre appender capable of sending gelf messages to a remote host.
-
-  Parameters:
-  *`gelf-server` - An IP address or hostname string of the remote logging server.
-  *`port` - the TCP or UDP port on which the server listens.
-  *`protocol` - OPTIONAL, Use :tcp or :udp (default) transport to send messages.
-
-  Returns a map, where :fn is the function timbre will call with a log message."
-  ([gelf-server port] (gelf-appender gelf-server port :udp))
+  "Returns a Timbre appender that sends gelf messages to a remote host. Params:
+    `gelf-server` - IP address or hostname string of the remote logging server
+    `port`        - TCP or UDP port on which the server listens
+    `protocol`    - e/o #{:tcp :udp}, defaults to :udp"
+  ([gelf-server port         ] (gelf-appender gelf-server port :udp))
   ([gelf-server port protocol]
    (let [tranport (make-gelf-transport gelf-server port protocol)]
      {:enabled?       true
@@ -47,11 +47,11 @@
       :rate-limit     nil
       :output-fn      :inherit
       :gelf-transport tranport
-
-      :fn             (fn [data]
-                        (let [{:keys [appender msg_ level hostname_]} data
-                              gelf-transport (:gelf-transport appender)
-                              log-level (timbre-to-gelf-level level)
-                              gelf-message (-> (GelfMessageBuilder. @msg_ @hostname_)
-                                             (.level log-level) .build)]
-                          (.send gelf-transport gelf-message)))})))
+      :fn
+      (fn [data]
+        (let [{:keys [appender msg_ level hostname_]} data
+              gelf-transport (:gelf-transport appender)
+              log-level      (timbre-to-gelf-level level)
+              gelf-message   (-> (GelfMessageBuilder. (force msg_) (force hostname_))
+                                 (.level log-level) .build)]
+          (.send gelf-transport gelf-message)))})))