[new] [#447] [Community adapters] Add Jetty 11 adapter (@alexandergunnarson)

Not officially tested, waiting on confirmation from users that this works as intended

Author: alexandergunnarson

src/taoensso/sente/server_adapters/community/jetty.clj

@@ -0,0 +1,111 @@
+(ns taoensso.sente.server-adapters.community.jetty
+  "Sente adapter for `ring-jetty-adapter`,
+  Ref. <https://github.com/ring-clojure/ring/tree/master/ring-jetty-adapter>.
+  Adapted from <https://github.com/taoensso/sente/pull/426#issuecomment-1647231979>."
+  {:author "Alex Gunnarson (@alexandergunnarson)"}
+  (:require
+    [ring.core.protocols       :as ring-protocols]
+    [ring.util.response        :as ring-response]
+    [ring.websocket            :as ws]
+    [ring.websocket.protocols  :as ws.protocols]
+    [taoensso.sente.interfaces :as i]
+    [taoensso.timbre :as timbre])
+
+  (:import
+    [org.eclipse.jetty.websocket.api WebSocketListener]
+    [ring.websocket.protocols Socket]))
+
+;;;; WebSockets
+
+(extend-type WebSocketListener
+  i/IServerChan
+    (sch-open?  [sch] (.isOpen sch))
+    (sch-close! [sch] (.close  sch))
+    (sch-send!  [sch-listener _websocket? msg]
+      (ws.protocols/-send sch-listener msg)
+      true))
+
+(extend-type Socket
+  i/IServerChan
+    (sch-open?  [sch] (ws.protocols/-open? sch))
+    (sch-close! [sch] (ws.protocols/-close sch nil nil))
+    (sch-send!  [sch-socket _websocket? msg]
+      (ws.protocols/-send sch-socket msg)
+      true))
+
+(defn- respond-ws
+  [{:keys [websocket-subprotocols]}
+   {:keys [on-close on-error on-msg on-open]}]
+
+  {:ring.websocket/protocol (first websocket-subprotocols)
+   :ring.websocket/listener
+   (reify ws.protocols/Listener
+     (on-close   [_ sch status _] (on-close sch true status))
+     (on-error   [_ sch error]    (on-error sch true error))
+     (on-message [_ sch msg]      (on-msg   sch true msg))
+     (on-open    [_ sch]          (on-open  sch true))
+     (on-pong    [_ sch data]))})
+
+;;;; Ajax
+
+(defprotocol ISenteJettyAjaxChannel
+  (ajax-read! [sch]))
+
+(deftype SenteJettyAjaxChannel [resp-promise_ open?_ on-close adapter-opts]
+  i/IServerChan
+  (sch-send!  [sch _websocket? msg] (deliver resp-promise_ msg) (i/sch-close! sch))
+  (sch-open?  [sch] @open?_)
+  (sch-close! [sch]
+    (when (compare-and-set! open?_ true false)
+      (deliver resp-promise_ nil)
+      (when on-close (on-close sch false nil))
+      true))
+
+  ISenteJettyAjaxChannel
+  (ajax-read! [_sch]
+    (let [{:keys [ajax-resp-timeout-ms]} adapter-opts]
+      (if ajax-resp-timeout-ms
+        (deref resp-promise_ ajax-resp-timeout-ms nil)
+        (deref resp-promise_)))))
+
+(defn- ajax-ch
+  [{:keys [on-open on-close]} adapter-opts]
+  (let [open?_ (atom true)
+        sch    (SenteJettyAjaxChannel. (promise) open?_ on-close adapter-opts)]
+    (when on-open (on-open sch false))
+    sch))
+
+(extend-protocol ring-protocols/StreamableResponseBody
+  SenteJettyAjaxChannel
+  (write-body-to-stream [body _response ^java.io.OutputStream output-stream]
+    ;; Use `future` because `output-stream` might block the thread,
+    ;; Ref. <https://github.com/ring-clojure/ring/issues/254#issuecomment-236048380>
+    (future
+      (try
+        (.write output-stream (.getBytes ^String (ajax-read! body) java.nio.charset.StandardCharsets/UTF_8))
+        (.flush output-stream)
+        (catch Throwable t
+          (timbre/error  t))
+        (finally
+          (.close output-stream))))))
+
+;;;; Adapter
+
+(deftype JettyServerChanAdapter [adapter-opts]
+  i/IServerChanAdapter
+  (ring-req->server-ch-resp [_ request callbacks-map]
+    (if (ws/upgrade-request? request)
+      (respond-ws request callbacks-map)
+      (ring-response/response (ajax-ch callbacks-map adapter-opts)))))
+
+(defn get-sch-adapter
+  "Returns an Jetty ServerChanAdapter. Options:
+     `:ajax-resp-timeout-ms` - Max msecs to wait for Ajax responses (default 60 secs)"
+  ([] (get-sch-adapter nil))
+  ([{:as   opts
+     :keys [ajax-resp-timeout-ms]
+     :or   {ajax-resp-timeout-ms (* 60 1000)}}]
+
+   (JettyServerChanAdapter.
+     (assoc opts
+       :ajax-resp-timeout-ms ajax-resp-timeout-ms))))