:destroy callback runs after server stop

src/ring/server/standalone.clj

@@ -12,18 +12,28 @@
              (try-port port run-server)
              (throw ex))))))
 
-(defn- setup-callbacks [{:keys [init destroy]}]
-  (if init (init))
-  (if destroy
-    (. (Runtime/getRuntime)
-       (addShutdownHook (Thread. destroy)))))
+(defmacro ^:private in-thread [& body]
+  `(doto (Thread. (fn [] ~@body))
+     (.start)))
+
+(defn- run-server [server destroy]
+  (in-thread
+   (try (.join server)
+        (finally (if destroy (destroy))))))
 
 (defn serve
   "Start a web server to run a handler."
-  [handler & [{:as options}]]
-  (setup-callbacks options)
+  [handler & [{:keys [init destroy join?] :as options}]]
+  (let [options (assoc options :join? false)
+        destroy (if destroy (memoize destroy))]
+    (if init (init))
+    (if destroy
+      (. (Runtime/getRuntime)
+         (addShutdownHook (Thread. destroy))))
     (try-port (port options)
       (fn [port]
-      (run-jetty
-        handler
-        (merge {:port port} options)))))
+        (let [options (merge {:port port} options) 
+              server  (run-jetty handler options)
+              thread  (run-server server destroy)]
+          (if join? (.join thread))
+          server)))))

test/ring/server/test/standalone.clj

@@ -43,4 +43,11 @@
   (testing ":init option"
     (let [ran-init? (atom false)]
       (with-server (test-server {:init #(reset! ran-init? true)})
-        (is @ran-init?)))))
+        (is @ran-init?))))
+
+  (testing ":destroy option"
+    (let [ran-destroy? (atom false)]
+      (with-server (test-server {:destroy #(reset! ran-destroy? true)})
+        (is (not @ran-destroy?)))
+      (Thread/sleep 100)
+      (is @ran-destroy?))))