Make portal.runtime/id globally unique per process

This will avoid issues with cache eviction after re-connection and other
potential issues with implicitly scoping ids per web socket connection.

Author: djblue

src/portal/runtime.cljc

@@ -15,9 +15,10 @@
     (print (:rep value))))
 
 (defonce default-options (atom nil))
+(defonce ^:private last-id (atom 0))
 
 (defonce ^:dynamic *session* nil)
-(defn- next-id [] (swap! (:id *session*) inc))
+(defn- next-id [] (swap! last-id inc))
 (defonce sessions (atom {}))
 
 (defn get-session [session-id]
@@ -29,8 +30,7 @@
 (defn open-session [{:keys [session-id] :as session}]
   (merge
    (get-session session-id)
-   {:id             (atom 0)
-    :value-cache    (atom {})
+   {:value-cache    (atom {})
     :watch-registry (atom #{})}
    session))