publish a `:database-update` event and create an event listener which calls...

publish a `:database-update` event and create an event listener which calls our driver notify-database-updated method whenever we get a :database-update event.

src/metabase/api/database.clj

@@ -127,7 +127,8 @@
                                        :engine engine
                                        :details details
                                        :is_full_sync is_full_sync))
-          (Database id))
+          (->> (Database id)
+               (events/publish-event :database-update)))
         ;; failed to connect, return error
         {:status 400
          :body   conn-error}))))

src/metabase/events/driver_notifications.clj

+(ns metabase.events.driver-notifications
+  (:require [clojure.core.async :as async]
+            [clojure.tools.logging :as log]
+            [metabase.db :as db]
+            [metabase.driver :as driver]
+            [metabase.events :as events]
+            [metabase.models.database :refer [Database]]))
+
+
+(def ^:const driver-notifications-topics
+  "The `Set` of event topics which are subscribed to for use in driver notifications."
+  #{:database-update})
+
+(def ^:private driver-notifications-channel
+  "Channel for receiving event notifications we want to subscribe to for driver notifications events."
+  (async/chan))
+
+
+;;; ## ---------------------------------------- EVENT PROCESSING ----------------------------------------
+
+
+(defn process-driver-notifications-event
+  "Handle processing for a single event notification received on the driver-notifications-channel"
+  [driver-notifications-event]
+  ;; try/catch here to prevent individual topic processing exceptions from bubbling up.  better to handle them here.
+  (try
+    (when-let [{topic :topic database :item} driver-notifications-event]
+      ;; notify the appropriate driver about the updated database
+      (driver/notify-database-updated (driver/engine->driver (:engine database)) database))
+    (catch Throwable e
+      (log/warn (format "Failed to process driver notifications event. %s" (:topic driver-notifications-event)) e))))
+
+
+
+;;; ## ---------------------------------------- LIFECYLE ----------------------------------------
+
+
+(defn events-init
+  "Automatically called during startup; start event listener for database sync events."
+  []
+  (events/start-event-listener driver-notifications-topics driver-notifications-channel process-driver-notifications-event))