| """ |
| 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 |
| |