poc-db-component.clj

(defrecord Database [host port connection]
  component/Lifecycle
  (start [component]
    (let [conn (connect-to-database host port)]
      (assoc component :connection conn)))
  (stop [component]
    (.close connection)
    (assoc component :connection nil)))

(defrecord Dashboard [database datasources options dashboard]
  component/Lifecycle
  (start  [component]
    (let [datasources-with-db (map #(assoc-in % [:params 0] database) datasources)]
      (assoc component :dashboard (ds/start datasources-with-db options))))
  (stop [component]
    (.stop dashboard)
    (assoc component :dashboard nil)))
  
(def my-system (component/system-map
                 :database (map->Database {:host <host> :port <port>})
                 :dashboard (component/using (map->Dashboard <datasources> <options>) [:database])))