Extend taggable-mixin to support different Tag models.
Usage is pretty simple. Tag model is default in Taggable constructor but you
can call it with different model like GHOPTaskType that inherits from Tag model.
Both Taggable and Tag models have been updated and they don't use hardcoded Tag
model anymore and instead use cls of class methods or self.__class__. In case
of Taggable it's self.__tag_model.
"""
YAML serializer.
Requires PyYaml (http://pyyaml.org/), but that's checked for in __init__.
"""
from StringIO import StringIO
import yaml
from django.db import models
from django.core.serializers.python import Serializer as PythonSerializer
from django.core.serializers.python import Deserializer as PythonDeserializer
class Serializer(PythonSerializer):
"""
Convert a queryset to YAML.
"""
internal_use_only = False
def handle_field(self, obj, field):
# A nasty special case: base YAML doesn't support serialization of time
# types (as opposed to dates or datetimes, which it does support). Since
# we want to use the "safe" serializer for better interoperability, we
# need to do something with those pesky times. Converting 'em to strings
# isn't perfect, but it's better than a "!!python/time" type which would
# halt deserialization under any other language.
if isinstance(field, models.TimeField) and getattr(obj, field.name) is not None:
self._current[field.name] = str(getattr(obj, field.name))
else:
super(Serializer, self).handle_field(obj, field)
def end_serialization(self):
self.options.pop('stream', None)
self.options.pop('fields', None)
yaml.safe_dump(self.objects, self.stream, **self.options)
def getvalue(self):
return self.stream.getvalue()
def Deserializer(stream_or_string, **options):
"""
Deserialize a stream or string of YAML data.
"""
if isinstance(stream_or_string, basestring):
stream = StringIO(stream_or_string)
else:
stream = stream_or_string
for obj in PythonDeserializer(yaml.load(stream)):
yield obj