Bump java-dogstastd-client to support env-var based configuration (#17)

The underlying library supports using the envvars DD_AGENT_HOST, DD_DOGSTATSD_PORT and DD_ENTITY_ID to configure the client.

The change in this PR removes the "custom" configuration in this library so that we defer all contextual setup to the underlying library. This slightly alters the default behaviour by requiring consumers to set the host explicity (through envvars or the host option).

Closes #15

project.clj

@@ -6,7 +6,7 @@
             :comments "Copyright (c) 2018 Unbounce Marketing Solutions Inc."}
   :profiles {:dev {:dependencies [[org.clojure/test.check "0.9.0"]]}}
   :dependencies [[org.clojure/clojure "1.9.0"]
-                 [com.datadoghq/java-dogstatsd-client "2.6.1"]]
+                 [com.datadoghq/java-dogstatsd-client "2.8"]]
   :global-vars {*warn-on-reflection* true}
   :deploy-repositories {"releases" {:url "https://repo.clojars.org" :creds :gpg}}
   )

src/com/unbounce/dogstatsd/core.clj

@@ -23,24 +23,28 @@
 (defn setup!
   "Sets up the statsd client.
 
-  By default, assumes localhost and port 8125. You can change the host and port with:
+  If :host is not explicitly specified, it will defer to the environment variable DD_AGENT_HOST.
+  If :port is not explicitly specified, it will first try to read it from the env var DD_DOGSTATSD_PORT, and then fallback to the default port 8125.
+
+  Examples:
+
+  To setup the client on host \"some-other-post\" and port 1234
 
     (setup! :host \"some-other-host\" :port 1234)
 
   To setup the client once and avoid reloading it, use :once?
 
-    (setup! :once? true)
-
+    (setup! :host \"some-other-host\" :once? true)
   "
-  [& {:keys [^String host ^long port ^String prefix #^"[Ljava.lang.String;" tags once?]}]
+  [& {:keys [^String host ^long port ^String prefix tags once?]}]
   (when-not (and client once?)
     (shutdown!)
     (alter-var-root #'client (constantly
                               (com.timgroup.statsd.NonBlockingStatsDClient.
                                prefix
-                               (or host "localhost")
-                               (or port 8125)
-                               tags)))))
+                               host
+                               (or port 0)
+                               (str-array tags))))))
 
 (defn increment
   ([metric]
@@ -165,9 +169,11 @@
   (.recordSetValue client metric value tags))
 
 (comment
-  (setup!)
+  (setup! :host "localhost" :port 8125 :tags #{"hello" "world"})
 
+  ;; In a terminal, setup `nc -u -l 8125` to watch for events
   (event {:title "foo" :text "things are bad\nfoo"} nil)
+  (increment "foo.bar")
 
   (service-check {:name "hi" :status :warning} nil)
   (service-check {:name "hi" :status :ok :timestamp 10 :check-run-id 123 :message "foo" :hostname "blah"} nil)