file db stuff

src/libs/db.clj

@@ -0,0 +1,40 @@
+(ns libs.db
+  (:use (libs app io maps)))
+
+(defn app-db
+  ([path] (app-db path {}))
+  ([path defaults]
+     (agent defaults
+            :meta {:db       :file
+                   :file     (app-file path)
+                   :defaults defaults})))
+
+(defn get* [db & path]
+  (get-in @db path))
+
+(defn set* [db & args]
+  (let [value (last args)
+        path  (butlast args)]
+    (send db assoc-in path value)))
+
+(def db-type (comp :db meta))
+
+(defmulti read-db  db-type)
+(defmulti write-db db-type)
+
+(defn clear-db [db]
+  (send db (fn [_] (:defaults (meta db)))))
+
+(defmethod read-db :file [db]
+  (let [{:keys [file defaults]} (meta db)]
+    (send db
+          (constantly
+           (patch-map
+            defaults
+            (deserialize file))))))
+
+(defmethod write-db :file [db]
+  (let [{:keys [file defaults]} (meta db)]
+    (serialize file
+               (diff-map @db
+                         defaults))))