Minor updates to web + highlight http-kit diffs

immutant · Jul 20, 2015 · 2e389b9 · 2e389b9
1 parent 08b03a0
commit 2e389b9
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Showing 2 changed files with 48 additions and 6 deletions.
diff --git a/src/demo/http_kit.clj b/src/demo/http_kit.clj
@@ -0,0 +1,38 @@
+(ns demo.http-kit
+  "Show API differences between Immutant and HTTP Kit"
+  (:require [immutant.web             :as web]
+            [immutant.web.async       :as async]))
+
+#_(defn async-handler
+  "For comparison, the actual http-kit example"
+  [ring-request]
+  ;; unified API for WebSocket and HTTP long polling/streaming
+  (with-channel ring-request channel    ; get the channel
+    (if (websocket? channel)            ; if you want to distinguish them
+      (on-receive channel (fn [data]     ; two way communication
+                            (send! channel data)))
+      (send! channel {:status 200
+                      :headers {"Content-Type" "text/plain"}
+                      :body    "Long polling?"}))))
+
+(defn async-handler
+  "Immutant version of http-kit example showing websocket degrade
+
+  Differences:
+  - Channel passed as callback param instead of macro param
+  - Channel not closed after send, by default
+  - All ring body types supported
+  - Automatic chunking of large (>16K) content"
+  [ring-request]
+  (async/as-channel ring-request
+    {:on-message (fn [channel data]
+                   (async/send! channel data))
+     :on-open    (fn [channel]
+                   (if-not (:websocket? ring-request)
+                     (async/send! channel {:status 200
+                                           :headers {"Content-Type" "text/plain"}
+                                           :body    "Long polling?"}
+                       :close? true)))}))
+
+(defn -main [& {:as args}]
+  (web/run async-handler :path "/http-kit"))
diff --git a/src/demo/web.clj b/src/demo/web.clj
@@ -16,7 +16,8 @@
     (content-type "text/plain")))
 
 (defn counter
-  "From https://github.com/ring-clojure/ring/wiki/Sessions"
+  "An example manipulating session state from
+  https://github.com/ring-clojure/ring/wiki/Sessions"
   [{session :session}]
   (let [count (:count session 0)
         session (assoc session :count (inc count))]
@@ -25,6 +26,7 @@
       (assoc :session session))))
 
 (defn sse-countdown
+  "An example of Server Sent Events"
   [request]
   (sse/as-channel request
     {:on-open (fn [ch]
@@ -34,26 +36,28 @@
                 ;; Signal the client to call EventSource.close()
                 (sse/send! ch {:event "close", :data "bye!"}))}))
 
+
+;;; Compose routes from above functions
 (defroutes routes
   (GET "/" {c :context} (redirect (str c "/index.html")))
   (GET "/counter" [] counter)
   (GET "/sse" [] sse-countdown)
   (route/resources "/")
   (ANY "*" [] echo))
 
-(def websocket-callbacks
-  "WebSocket callback functions"
+(def demo-app-callbacks
+  "Callbacks for websocket.html/app.js example"
   {:on-open    (fn [channel]
                  (async/send! channel "Ready to reverse your messages!"))
    :on-close   (fn [channel {:keys [code reason]}]
                  (println "close code:" code "reason:" reason))
-   :on-message (fn [ch m]
-                 (async/send! ch (apply str (reverse m))))})
+   :on-message (fn [channel m]
+                 (async/send! channel (apply str (reverse m))))})
 
 (defn -main [& {:as args}]
   (web/run
     (-> routes
       (immutant/wrap-session {:timeout 20})
-      (immutant/wrap-websocket websocket-callbacks))
+      (immutant/wrap-websocket demo-app-callbacks))
     (merge {"host" (env :demo-web-host), "port" (env :demo-web-port)}
       args)))