Add new python field.

common/lib/xmodule/xmodule/fields.py

@@ -2,7 +2,7 @@ import time
 import logging
 import re
 
-from xblock.fields import Field
+from xblock.fields import Field, String
 import datetime
 import dateutil.parser
 
@@ -116,3 +116,16 @@ class Timedelta(Field):
             if cur_value > 0:
                 values.append("%d %s" % (cur_value, attr))
         return ' '.join(values)
+
+
+class IsoTime(String):
+
+    def from_json(self, value):
+        if isinstance(value, float):
+            if not value:
+                return "00:00:00"
+            else:
+                return str(datetime.timedelta(seconds=value))
+        else:
+            return super(IsoTime, self).from_json(value)
+

common/lib/xmodule/xmodule/video_module.py

@@ -28,13 +28,15 @@ from xmodule.editing_module import TabsEditingDescriptor
 from xmodule.raw_module import EmptyDataRawDescriptor
 from xmodule.xml_module import is_pointer_tag, name_to_pathname, deserialize_field
 from xmodule.modulestore import Location
-from xblock.fields import Scope, String, Boolean, Float, List, Integer, ScopeIds
+from xblock.fields import Scope, String, Boolean, List, Integer, ScopeIds
+from xmodule.fields import IsoTime
 
 from xmodule.modulestore.inheritance import InheritanceKeyValueStore
 from xblock.runtime import DbModel
 log = logging.getLogger(__name__)
 
 
+
 def parse_time_from_str_to_float(str_time):
     """
     Converts s in '12:34:45' format to seconds.
@@ -62,16 +64,6 @@ def parse_time_from_float_to_str(s):
     else:
         return str(datetime.timedelta(seconds=s))
 
-
-class StringThatWasFloat(String):
-
-    def from_json(self, value):
-        if isinstance(value, float):
-            return parse_time_from_float_to_str(value)
-        else:
-            return super(StringThatWasFloat, self).from_json(value)
-
-
 class VideoFields(object):
     """Fields for `VideoModule` and `VideoDescriptor`."""
     display_name = String(
@@ -116,13 +108,13 @@ class VideoFields(object):
         scope=Scope.settings,
         default=""
     )
-    start_time = StringThatWasFloat(
+    start_time = IsoTime(
         help="Start time for the video.",
         display_name="Start Time",
         scope=Scope.settings,
         default="00:00:00"
     )
-    end_time = StringThatWasFloat(
+    end_time = IsoTime(
         help="End time for the video.",
         display_name="End Time",
         scope=Scope.settings,

common/lib/xmodule/xmodule/x_module.py

@@ -13,6 +13,7 @@ from xmodule.modulestore.exceptions import ItemNotFoundError, InsufficientSpecif
 
 from xblock.core import XBlock
 from xblock.fields import Scope, Integer, Float, List, XBlockMixin, String
+from xmodule.fields import IsoTime
 from xblock.fragment import Fragment
 from xblock.runtime import Runtime
 from xmodule.errortracker import exc_info_to_str
@@ -708,6 +709,8 @@ class XModuleDescriptor(XModuleMixin, HTMLSnippet, ResourceTemplates, XBlock):
                 editor_type = "Float"
             elif isinstance(field, List):
                 editor_type = "List"
+            elif isinstance(field, IsoTime):
+                editor_type = "IsoTime"
             metadata_fields[field.name]['type'] = editor_type
             metadata_fields[field.name]['options'] = [] if values is None else values