ConnInfo

- `getDB(string)` will now throw `BirchwoodException` with `ErrorType.DB_KEY_NOT_FOUND` if the key is not found

Exceptions

- Added member `DB_KEY_NOT_FOUND` to `ErrorType` enum

source/birchwood/client/exceptions.d

@@ -66,7 +66,12 @@ public enum ErrorType
      * If invalid parameters are passed
      * to any of the text formatting functions
      */
-    INVALID_FORMATTING
+    INVALID_FORMATTING,
+
+    /** 
+     * If a key-lookup in the ConnInfo failed
+     */
+    DB_KEY_NOT_FOUND
 }
 
 /** 

source/birchwood/config/conninfo.d

@@ -136,8 +136,7 @@ public shared struct ConnectionInfo
         }
         else
         {
-            // TODO: Should throw an exception
-            return "";
+            throw new BirchwoodException(ErrorType.DB_KEY_NOT_FOUND, "Could not find key '"~key~"'");
         }
     }