adding doc comments and changing some internal use functions to private

clj-browserchannel/src/net/thegeez/browserchannel/client.cljs

@@ -4,21 +4,17 @@
     [dommy.core :refer-macros [sel1]]
     goog.net.BrowserChannel
     goog.net.BrowserChannel.Handler
-    [goog.net.BrowserChannel.State :as bc-state]
     [goog.events :as events]
     [goog.debug.Logger.Level :as log-level]))
 
 (defonce channel (goog.net.BrowserChannel.))
 
-(def default-options
+; see: https://google.github.io/closure-library/api/source/closure/goog/net/browserchannel.js.src.html#l470
-  {:base                            "/channel"
+(def ^:private bch-state-enum-to-keyword
-   :allow-chunked-mode?             true
+  {0 :closed
-   :allow-host-prefix?              true
+   1 :init
-   :fail-fast?                      false
+   2 :opening
-   :max-back-channel-retries        3
+   3 :opened})
-   :max-forward-channel-retries     2
-   :forward-channel-request-timeout (* 20 1000)
-   :verbose-logging?                false})
 
 ; see: https://google.github.io/closure-library/api/source/closure/goog/net/browserchannel.js.src.html#l521
 (def ^:private bch-error-enum-to-keyword
@@ -34,19 +30,19 @@
    11 :bad-response
    12 :active-x-blocked})
 
-(defn encode-map
+(defn- encode-map
   [data]
   (doto (js-obj)
     (aset "__edn" (pr-str data))))
 
-(defn decode-map
+(defn- decode-map
   [m]
   (let [m (js->clj m)]
     (if (contains? m "__edn")
       (reader/read-string (str (get m "__edn")))
       m)))
 
-(defn decode-queued-map
+(defn- decode-queued-map
   [queued-map]
   (merge
     {:context (aget queued-map "context")
@@ -56,40 +52,52 @@
         {:data (reader/read-string (str (get data "__edn")))}
         {:map data}))))
 
-(defn decode-queued-map-array
+(defn- decode-queued-map-array
   [queued-map-array]
   (mapv decode-queued-map queued-map-array))
 
-(defn channel-state []
+(defn channel-state
-  (.getState channel))
+  "returns the current state of the browserchannel connection."
+  []
+  (get bch-state-enum-to-keyword (.getState channel) :unknown))
 
 (defn connected?
+  "returns true if the browserchannel connection is currently connected."
   []
-  (= (channel-state) bc-state/OPENED))
+  (= (channel-state) :opened))
 
 (defn set-debug-log!
+  "sets the debug log level, and optionally a log output handler function
+   which defaults to js/console.log"
   [level & [f]]
   (doto (.. channel getChannelDebug getLogger)
     (.setLevel level)
     (.addHandler (or f #(js/console.log %)))))
 
 (defn send-data
+  "sends data to the server over the forward channel. when the data has
+   been sent and the server sends an acknowledgement, the optional
+   on-success callback is invoked."
   [data & [{:keys [on-success]}]]
   (if data
     (.sendMap channel (encode-map data) {:on-success on-success})))
 
 (defn connect!
+  "starts the browserchannel connection (initiates a connection to the server).
+   under normal circumstances, your application should not call this directly.
+   instead your application code should call init!"
   [& [{:keys [base] :as options}]]
   (let [state (channel-state)]
-    (if (or (= state bc-state/CLOSED)
+    (if (or (= state :closed)
-            (= state bc-state/INIT))
+            (= state :init))
       (.connect channel
                 (str base "/test")
                 (str base "/bind")))))
 
 (defn disconnect!
+  "disconnects and closes the browserchannel connection."
   []
-  (if-not (= (channel-state) bc-state/CLOSED)
+  (if-not (= (channel-state) :closed)
     (.disconnect channel)))
 
 (defn- get-anti-forgery-token
@@ -97,7 +105,7 @@
   (if-let [tag (sel1 "meta[name='anti-forgery-token']")]
     (.-content tag)))
 
-(defn ->handler
+(defn- ->handler
   [{:keys [on-open on-close on-receive on-sent on-error]}]
   (let [handler (goog.net.BrowserChannel.Handler.)]
     (set! (.-channelOpened handler)
@@ -142,14 +150,62 @@
   ;;       setting to be able to change, so i think it's worth the risk...
   (set! goog.net.BrowserChannel/BACK_CHANNEL_MAX_RETRIES (:max-back-channel-retries options)))
 
+(def default-options
+  "default options that will be applied by init! unless
+   overridden."
+  {
+   ;; base/root url on which to send browserchannel requests to
+   :base                            "/channel"
+
+   ;; sets whether chunked mode is allowed. sometimes a useful
+   ;; debugging tool
+   :allow-chunked-mode?             true
+
+   ;; sets whether the channel allows the user of a subdomain
+   :allow-host-prefix?              true
+
+   ;; when true, this changes the behaviour of the forward channel
+   ;; (client->server) such that it will not retry failed requests
+   ;; even once.
+   :fail-fast?                      false
+
+   ;; sets the max number of attempts to connect to the server for
+   ;; back channel (server->client) requests
+   :max-back-channel-retries        3
+
+   ;; sets the max number of attempts to connect to the server for
+   ;; forward channel (client->server) requests
+   :max-forward-channel-retries     2
+
+   ;; sets the timeout (in milliseconds) for a forward channel request
+   :forward-channel-request-timeout (* 20 1000)
+
+   ;; whether to enable somewhat verbose debug logging
+   :verbose-logging?                false
+   })
+
 (defn init!
+  "initializes a browserchannel connection for use, registers your
+   application event handlers and setting any specified options.
+
+   handler should be a map of event handler functions:
+
+   {:on-open    (fn [] ...)
+    :on-close   (fn [pending undelivered] ...)
+    :on-receive (fn [data] ...)
+    :on-sent    (fn [delivered] ...)
+    :on-error   (fn [error-code] ...)
+
+    :on-open is called when a connection is (re-)established.
+    :on-close is called when a connection is closed.
+    :on-receive is called when data is received from the server.
+    :on-sent is called when data has been successfully sent to
+    the server ('delivered' is a list of what was sent).
+    :on-error is only invoked once just before the connection is
+    closed, and only if there was an error."
   [handler & [options]]
   (let [options (merge default-options options)]
-    (events/listen
+    (events/listen js/window "unload" #(disconnect!))
-      js/window "unload"
-      (fn []
-        (disconnect!)))
-
     (.setHandler channel (->handler handler))
     (apply-options! options)
     (let [csrf-token (get-anti-forgery-token)