Redesigned the babel_format_bytes() localization method.

The method for outputting the byte sizes in human readable and localized strings was redesigned.

lib/hawat/app.py

@@ -705,42 +705,30 @@ def _setup_app_babel(app):
         flask.g.locale = flask.session.get('locale', get_locale())
         flask.g.timezone = flask.session.get('timezone', get_timezone())
 
-    def babel_format_bytes(size, unit = 'B'):
+    def babel_format_bytes(size, unit = 'B', step_size = 1024):
         """
         Format given numeric value to human readable string describing size in
         B/KB/MB/GB/TB.
 
-        :param dict baseparams: Original query parameters.
-        :param dict updates: Updates for query parameters.
-        :return: Deep copy of original parameters modified with given updates.
-        :rtype: dict
-        """
-        while True:
-            if unit == 'B':
-                if size > 1024:
-                    size = size / 1024
-                    unit = 'KB'
-                else:
-                    break
-            if unit == 'KB':
-                if size > 1024:
-                    size = size / 1024
-                    unit = 'MB'
-                else:
-                    break
-            if unit == 'MB':
-                if size > 1024:
-                    size = size / 1024
-                    unit = 'GB'
-                else:
-                    break
-            if unit == 'GB':
-                if size > 1024:
-                    size = size / 1024
-                    unit = 'TB'
-                else:
-                    break
-            break
+        :param int size: Number to be formatted.
+        :param enum unit: Starting unit, possible values are ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB'].
+        :param int step_size: Size of the step between units.
+        :return: Formatted and localized string.
+        :rtype: string
+        """
+        units = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB']
+        idx_max = len(units) - 1
+        unit = unit.upper()
+        for idx, val in enumerate(units):
+            # Skip the last step, there is no next unit defined after exabyte.
+            if idx == idx_max:
+                break
+            if size > step_size:
+                if unit == val:
+                    size = size / step_size
+                    unit = units[idx+1]
+            else:
+                break
         return '{} {}'.format(
             flask_babel.format_decimal(size),
             unit