add `hostname` util, which checks conf before guessing local-hostname
diff --git a/storm-core/src/clj/backtype/storm/util.clj b/storm-core/src/clj/backtype/storm/util.clj
index 398584f..4dbb101 100644
--- a/storm-core/src/clj/backtype/storm/util.clj
+++ b/storm-core/src/clj/backtype/storm/util.clj
@@ -206,6 +206,12 @@
(def memoized-local-hostname (memoize local-hostname))
+;; checks conf for STORM-LOCAL-HOSTNAME.
+;; when unconfigured, falls back to (memoized) guess by `local-hostname`.
+(defn hostname
+ [conf]
+ (conf STORM-LOCAL-HOSTNAME (memoized-local-hostname)))
+
(letfn [(try-port [port]
(with-open [socket (java.net.ServerSocket. port)]
(.getLocalPort socket)))]
