From 1d9e945527eac6abfd4c0dff9fe630229d553b13 Mon Sep 17 00:00:00 2001
From: Peter Taoussanis <peter@taoensso.com>
Date: Tue, 20 Sep 2022 15:17:29 +0200
Subject: [PATCH] [mod] [Undertow adapter] `close!` now returns `true` iff
 actually closed

---
 src/taoensso/sente/server_adapters/undertow.clj | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/taoensso/sente/server_adapters/undertow.clj b/src/taoensso/sente/server_adapters/undertow.clj
index f0812b0..8ca7703 100644
--- a/src/taoensso/sente/server_adapters/undertow.clj
+++ b/src/taoensso/sente/server_adapters/undertow.clj
@@ -45,9 +45,10 @@
   (sch-send!  [sch websocket? msg] (async/put! resp-ch msg (fn [_] (i/sch-close! sch))))
   (sch-open?  [sch] @open?_)
   (sch-close! [sch]
-    (when on-close (on-close sch false nil))
-    (reset! open?_ false)
-    (async/close! resp-ch))
+    (when (compare-and-set! open?_ true false)
+      (when on-close (on-close sch false nil))
+      (async/close! resp-ch)
+      true))
 
   ISenteUndertowAjaxChannel
   (ajax-read! [sch] (async/<!! resp-ch)))