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diff --git a/google_appengine/google/appengine/api/croninfo.py b/google_appengine/google/appengine/api/croninfo.py
new file mode 100755
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+++ b/google_appengine/google/appengine/api/croninfo.py
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+#!/usr/bin/env python
+#
+# Copyright 2007 Google Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+"""CronInfo tools.
+
+A library for working with CronInfo records, describing cron entries for an
+application. Supports loading the records from yaml.
+"""
+
+
+
+import logging
+import sys
+import traceback
+
+try:
+  import pytz
+except ImportError:
+  pytz = None
+
+from google.appengine.cron import groc
+from google.appengine.api import validation
+from google.appengine.api import yaml_builder
+from google.appengine.api import yaml_listener
+from google.appengine.api import yaml_object
+
+_URL_REGEX = r'^/.*$'
+_TIMEZONE_REGEX = r'^.{0,100}$'
+_DESCRIPTION_REGEX = r'^.{0,499}$'
+
+
+class GrocValidator(validation.Validator):
+  """Checks that a schedule is in valid groc format."""
+
+  def Validate(self, value):
+    """Validates a schedule."""
+    if value is None:
+      raise validation.MissingAttribute('schedule must be specified')
+    if not isinstance(value, basestring):
+      raise TypeError('schedule must be a string, not \'%r\''%type(value))
+    schedule = groc.CreateParser(value)
+    try:
+      schedule.timespec()
+    except groc.GrocException, e:
+      raise validation.ValidationError('schedule \'%s\' failed to parse: %s'%(
+          value, e.args[0]))
+    return value
+
+
+class TimezoneValidator(validation.Validator):
+  """Checks that a timezone can be correctly parsed and is known."""
+
+  def Validate(self, value):
+    """Validates a timezone."""
+    if value is None:
+      return
+    if not isinstance(value, basestring):
+      raise TypeError('timezone must be a string, not \'%r\'' % type(value))
+    if pytz is None:
+      return value
+    try:
+      pytz.timezone(value)
+    except pytz.UnknownTimeZoneError:
+      raise validation.ValidationError('timezone \'%s\' is unknown' % value)
+    except IOError:
+      return value
+    except:
+      unused_e, v, t = sys.exc_info()
+      logging.warning('pytz raised an unexpected error: %s.\n' % (v) +
+                      'Traceback:\n' + '\n'.join(traceback.format_tb(t)))
+      raise
+    return value
+
+
+CRON = 'cron'
+
+URL = 'url'
+SCHEDULE = 'schedule'
+TIMEZONE = 'timezone'
+DESCRIPTION = 'description'
+
+
+class MalformedCronfigurationFile(Exception):
+  """Configuration file for Cron is malformed."""
+  pass
+
+
+class CronEntry(validation.Validated):
+  """A cron entry describes a single cron job."""
+  ATTRIBUTES = {
+      URL: _URL_REGEX,
+      SCHEDULE: GrocValidator(),
+      TIMEZONE: TimezoneValidator(),
+      DESCRIPTION: validation.Optional(_DESCRIPTION_REGEX)
+  }
+
+
+class CronInfoExternal(validation.Validated):
+  """CronInfoExternal describes all cron entries for an application."""
+  ATTRIBUTES = {
+      CRON: validation.Optional(validation.Repeated(CronEntry))
+  }
+
+
+def LoadSingleCron(cron_info):
+  """Load a cron.yaml file or string and return a CronInfoExternal object."""
+  builder = yaml_object.ObjectBuilder(CronInfoExternal)
+  handler = yaml_builder.BuilderHandler(builder)
+  listener = yaml_listener.EventListener(handler)
+  listener.Parse(cron_info)
+
+  cron_info = handler.GetResults()
+  if len(cron_info) < 1:
+    raise MalformedCronfigurationFile('Empty cron configuration.')
+  if len(cron_info) > 1:
+    raise MalformedCronfigurationFile('Multiple cron sections '
+                                      'in configuration.')
+  return cron_info[0]