mirror of https://github.com/django/django.git
Fixed #7052 -- Added support for natural keys in serialization.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@11863 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
Russell Keith-Magee
parent
44b9076bbe
commit
35cc439228
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@ -47,6 +47,13 @@ def check_password(raw_password, enc_password):
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class SiteProfileNotAvailable(Exception):
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pass
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class PermissionManager(models.Manager):
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def get_by_natural_key(self, codename, app_label, model):
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return self.get(
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codename=codename,
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content_type=ContentType.objects.get_by_natural_key(app_label, model)
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)
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class Permission(models.Model):
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"""The permissions system provides a way to assign permissions to specific users and groups of users.
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@ -63,6 +70,7 @@ class Permission(models.Model):
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name = models.CharField(_('name'), max_length=50)
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content_type = models.ForeignKey(ContentType)
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codename = models.CharField(_('codename'), max_length=100)
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objects = PermissionManager()
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class Meta:
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verbose_name = _('permission')
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@ -76,6 +84,10 @@ class Permission(models.Model):
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unicode(self.content_type),
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unicode(self.name))
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def natural_key(self):
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return (self.codename,) + self.content_type.natural_key()
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natural_key.dependencies = ['contenttypes.contenttype']
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class Group(models.Model):
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"""Groups are a generic way of categorizing users to apply permissions, or some other label, to those users. A user can belong to any number of groups.
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@ -8,6 +8,13 @@ class ContentTypeManager(models.Manager):
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# This cache is shared by all the get_for_* methods.
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_cache = {}
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def get_by_natural_key(self, app_label, model):
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try:
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ct = self.__class__._cache[(app_label, model)]
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except KeyError:
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ct = self.get(app_label=app_label, model=model)
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return ct
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def get_for_model(self, model):
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"""
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Returns the ContentType object for a given model, creating the
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@ -93,3 +100,6 @@ class ContentType(models.Model):
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so code that calls this method should catch it.
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"""
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return self.model_class()._default_manager.get(**kwargs)
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def natural_key(self):
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return (self.app_label, self.model)
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@ -13,6 +13,8 @@ class Command(BaseCommand):
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help='Specifies the indent level to use when pretty-printing output'),
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make_option('-e', '--exclude', dest='exclude',action='append', default=[],
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help='App to exclude (use multiple --exclude to exclude multiple apps).'),
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make_option('-n', '--natural', action='store_true', dest='use_natural_keys', default=False,
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help='Use natural keys if they are available.'),
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)
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help = 'Output the contents of the database as a fixture of the given format.'
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args = '[appname ...]'
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@ -24,6 +26,7 @@ class Command(BaseCommand):
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indent = options.get('indent',None)
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exclude = options.get('exclude',[])
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show_traceback = options.get('traceback', False)
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use_natural_keys = options.get('use_natural_keys', False)
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excluded_apps = [get_app(app_label) for app_label in exclude]
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@ -67,18 +70,86 @@ class Command(BaseCommand):
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except KeyError:
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raise CommandError("Unknown serialization format: %s" % format)
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# Now collate the objects to be serialized.
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objects = []
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for app, model_list in app_list.items():
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if model_list is None:
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model_list = get_models(app)
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for model in model_list:
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if not model._meta.proxy:
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objects.extend(model._default_manager.all())
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for model in sort_dependencies(app_list.items()):
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if not model._meta.proxy:
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objects.extend(model._default_manager.all())
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try:
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return serializers.serialize(format, objects, indent=indent)
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return serializers.serialize(format, objects, indent=indent,
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use_natural_keys=use_natural_keys)
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except Exception, e:
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if show_traceback:
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raise
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raise CommandError("Unable to serialize database: %s" % e)
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def sort_dependencies(app_list):
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"""Sort a list of app,modellist pairs into a single list of models.
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The single list of models is sorted so that any model with a natural key
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is serialized before a normal model, and any model with a natural key
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dependency has it's dependencies serialized first.
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"""
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from django.db.models import get_model, get_models
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# Process the list of models, and get the list of dependencies
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model_dependencies = []
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models = set()
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for app, model_list in app_list:
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if model_list is None:
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model_list = get_models(app)
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for model in model_list:
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models.add(model)
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# Add any explicitly defined dependencies
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if hasattr(model, 'natural_key'):
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deps = getattr(model.natural_key, 'dependencies', [])
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if deps:
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deps = [get_model(*d.split('.')) for d in deps]
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else:
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deps = []
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# Now add a dependency for any FK or M2M relation with
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# a model that defines a natural key
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for field in model._meta.fields:
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if hasattr(field.rel, 'to'):
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rel_model = field.rel.to
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if hasattr(rel_model, 'natural_key'):
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deps.append(rel_model)
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for field in model._meta.many_to_many:
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rel_model = field.rel.to
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if hasattr(rel_model, 'natural_key'):
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deps.append(rel_model)
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model_dependencies.append((model, deps))
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model_dependencies.reverse()
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# Now sort the models to ensure that dependencies are met. This
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# is done by repeatedly iterating over the input list of models.
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# If all the dependencies of a given model are in the final list,
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# that model is promoted to the end of the final list. This process
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# continues until the input list is empty, or we do a full iteration
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# over the input models without promoting a model to the final list.
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# If we do a full iteration without a promotion, that means there are
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# circular dependencies in the list.
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model_list = []
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while model_dependencies:
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skipped = []
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changed = False
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while model_dependencies:
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model, deps = model_dependencies.pop()
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if all((d not in models or d in model_list) for d in deps):
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# If all of the models in the dependency list are either already
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# on the final model list, or not on the original serialization list,
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# then we've found another model with all it's dependencies satisfied.
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model_list.append(model)
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changed = True
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else:
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skipped.append((model, deps))
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if not changed:
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raise CommandError("Can't resolve dependencies for %s in serialized app list." %
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', '.join('%s.%s' % (model._meta.app_label, model._meta.object_name)
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for model, deps in sorted(skipped, key=lambda obj: obj[0].__name__))
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)
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model_dependencies = skipped
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return model_list
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@ -33,6 +33,7 @@ class Serializer(object):
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self.stream = options.get("stream", StringIO())
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self.selected_fields = options.get("fields")
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self.use_natural_keys = options.get("use_natural_keys", False)
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self.start_serialization()
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for obj in queryset:
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@ -24,6 +24,7 @@ class Serializer(PythonSerializer):
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def end_serialization(self):
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self.options.pop('stream', None)
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self.options.pop('fields', None)
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self.options.pop('use_natural_keys', None)
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simplejson.dump(self.objects, self.stream, cls=DjangoJSONEncoder, **self.options)
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def getvalue(self):
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@ -47,17 +47,24 @@ class Serializer(base.Serializer):
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def handle_fk_field(self, obj, field):
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related = getattr(obj, field.name)
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if related is not None:
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if field.rel.field_name == related._meta.pk.name:
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# Related to remote object via primary key
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related = related._get_pk_val()
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if self.use_natural_keys and hasattr(related, 'natural_key'):
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related = related.natural_key()
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else:
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# Related to remote object via other field
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related = getattr(related, field.rel.field_name)
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self._current[field.name] = smart_unicode(related, strings_only=True)
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if field.rel.field_name == related._meta.pk.name:
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# Related to remote object via primary key
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related = related._get_pk_val()
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else:
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# Related to remote object via other field
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related = smart_unicode(getattr(related, field.rel.field_name), strings_only=True)
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self._current[field.name] = related
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def handle_m2m_field(self, obj, field):
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if field.rel.through._meta.auto_created:
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self._current[field.name] = [smart_unicode(related._get_pk_val(), strings_only=True)
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if self.use_natural_keys and hasattr(field.rel.to, 'natural_key'):
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m2m_value = lambda value: value.natural_key()
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else:
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m2m_value = lambda value: smart_unicode(value._get_pk_val(), strings_only=True)
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self._current[field.name] = [m2m_value(related)
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for related in getattr(obj, field.name).iterator()]
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def getvalue(self):
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@ -86,13 +93,28 @@ def Deserializer(object_list, **options):
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# Handle M2M relations
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if field.rel and isinstance(field.rel, models.ManyToManyRel):
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m2m_convert = field.rel.to._meta.pk.to_python
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m2m_data[field.name] = [m2m_convert(smart_unicode(pk)) for pk in field_value]
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if hasattr(field.rel.to._default_manager, 'get_by_natural_key'):
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def m2m_convert(value):
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if hasattr(value, '__iter__'):
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return field.rel.to._default_manager.get_by_natural_key(*value).pk
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else:
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return smart_unicode(field.rel.to._meta.pk.to_python(value))
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else:
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m2m_convert = lambda v: smart_unicode(field.rel.to._meta.pk.to_python(v))
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m2m_data[field.name] = [m2m_convert(pk) for pk in field_value]
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# Handle FK fields
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elif field.rel and isinstance(field.rel, models.ManyToOneRel):
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if field_value is not None:
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data[field.attname] = field.rel.to._meta.get_field(field.rel.field_name).to_python(field_value)
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if hasattr(field.rel.to._default_manager, 'get_by_natural_key'):
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if hasattr(field_value, '__iter__'):
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obj = field.rel.to._default_manager.get_by_natural_key(*field_value)
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value = getattr(obj, field.rel.field_name)
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else:
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value = field.rel.to._meta.get_field(field.rel.field_name).to_python(field_value)
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data[field.attname] = value
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else:
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data[field.attname] = field.rel.to._meta.get_field(field.rel.field_name).to_python(field_value)
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else:
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data[field.attname] = None
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@ -44,6 +44,7 @@ class Serializer(PythonSerializer):
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def end_serialization(self):
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self.options.pop('stream', None)
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self.options.pop('fields', None)
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self.options.pop('use_natural_keys', None)
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yaml.dump(self.objects, self.stream, Dumper=DjangoSafeDumper, **self.options)
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def getvalue(self):
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@ -81,13 +81,22 @@ class Serializer(base.Serializer):
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self._start_relational_field(field)
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related = getattr(obj, field.name)
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if related is not None:
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if field.rel.field_name == related._meta.pk.name:
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# Related to remote object via primary key
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related = related._get_pk_val()
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if self.use_natural_keys and hasattr(related, 'natural_key'):
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# If related object has a natural key, use it
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related = related.natural_key()
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# Iterable natural keys are rolled out as subelements
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for key_value in related:
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self.xml.startElement("natural", {})
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self.xml.characters(smart_unicode(key_value))
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self.xml.endElement("natural")
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else:
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# Related to remote object via other field
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related = getattr(related, field.rel.field_name)
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self.xml.characters(smart_unicode(related))
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if field.rel.field_name == related._meta.pk.name:
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# Related to remote object via primary key
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related = related._get_pk_val()
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else:
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# Related to remote object via other field
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related = getattr(related, field.rel.field_name)
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self.xml.characters(smart_unicode(related))
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else:
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self.xml.addQuickElement("None")
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self.xml.endElement("field")
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@ -100,8 +109,25 @@ class Serializer(base.Serializer):
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"""
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if field.rel.through._meta.auto_created:
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self._start_relational_field(field)
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if self.use_natural_keys and hasattr(field.rel.to, 'natural_key'):
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# If the objects in the m2m have a natural key, use it
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def handle_m2m(value):
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natural = value.natural_key()
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# Iterable natural keys are rolled out as subelements
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self.xml.startElement("object", {})
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for key_value in natural:
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self.xml.startElement("natural", {})
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self.xml.characters(smart_unicode(key_value))
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self.xml.endElement("natural")
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self.xml.endElement("object")
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else:
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def handle_m2m(value):
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self.xml.addQuickElement("object", attrs={
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'pk' : smart_unicode(value._get_pk_val())
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})
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for relobj in getattr(obj, field.name).iterator():
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self.xml.addQuickElement("object", attrs={"pk" : smart_unicode(relobj._get_pk_val())})
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handle_m2m(relobj)
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self.xml.endElement("field")
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def _start_relational_field(self, field):
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@ -187,16 +213,40 @@ class Deserializer(base.Deserializer):
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if node.getElementsByTagName('None'):
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return None
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else:
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return field.rel.to._meta.get_field(field.rel.field_name).to_python(
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getInnerText(node).strip())
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if hasattr(field.rel.to._default_manager, 'get_by_natural_key'):
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keys = node.getElementsByTagName('natural')
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if keys:
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# If there are 'natural' subelements, it must be a natural key
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field_value = [getInnerText(k).strip() for k in keys]
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obj = field.rel.to._default_manager.get_by_natural_key(*field_value)
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obj_pk = getattr(obj, field.rel.field_name)
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else:
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# Otherwise, treat like a normal PK
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field_value = getInnerText(node).strip()
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obj_pk = field.rel.to._meta.get_field(field.rel.field_name).to_python(field_value)
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return obj_pk
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else:
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field_value = getInnerText(node).strip()
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return field.rel.to._meta.get_field(field.rel.field_name).to_python(field_value)
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def _handle_m2m_field_node(self, node, field):
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"""
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Handle a <field> node for a ManyToManyField.
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"""
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return [field.rel.to._meta.pk.to_python(
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c.getAttribute("pk"))
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for c in node.getElementsByTagName("object")]
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if hasattr(field.rel.to._default_manager, 'get_by_natural_key'):
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def m2m_convert(n):
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keys = n.getElementsByTagName('natural')
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if keys:
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# If there are 'natural' subelements, it must be a natural key
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field_value = [getInnerText(k).strip() for k in keys]
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obj_pk = field.rel.to._default_manager.get_by_natural_key(*field_value).pk
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else:
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# Otherwise, treat like a normal PK value.
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obj_pk = field.rel.to._meta.pk.to_python(n.getAttribute('pk'))
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return obj_pk
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else:
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m2m_convert = lambda n: field.rel.to._meta.pk.to_python(n.getAttribute('pk'))
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return [m2m_convert(c) for c in node.getElementsByTagName("object")]
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def _get_model_from_node(self, node, attr):
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"""
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@ -234,6 +234,17 @@ name to ``dumpdata``, the dumped output will be restricted to that model,
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rather than the entire application. You can also mix application names and
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model names.
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.. django-admin-option:: --natural
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.. versionadded:: 1.2
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Use :ref:`natural keys <topics-serialization-natural-keys>` to represent
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any foreign key and many-to-many relationship with a model that provides
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a natural key definition. If you are dumping ``contrib.auth`` ``Permission``
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objects or ``contrib.contenttypes`` ``ContentType`` objects, you should
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probably be using this flag.
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flush
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-----
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@ -267,3 +267,13 @@ include %}`` tags).
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As a side effect, it is now much easier to support non-Django template
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languages. For more details, see the :ref:`notes on supporting
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non-Django template languages<topic-template-alternate-language>`.
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Natural keys in fixtures
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------------------------
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Fixtures can refer to remote objects using
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:ref:`topics-serialization-natural-keys`. This lookup scheme is an
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alternative to the normal primary-key based object references in a
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fixture, improving readability, and resolving problems referring to
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objects whose primary key value may not be predictable or known.
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@ -154,10 +154,10 @@ to install third-party Python modules:
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.. _PyYAML: http://www.pyyaml.org/
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Notes for specific serialization formats
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----------------------------------------
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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json
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~~~~
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^^^^
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If you're using UTF-8 (or any other non-ASCII encoding) data with the JSON
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serializer, you must pass ``ensure_ascii=False`` as a parameter to the
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@ -191,3 +191,191 @@ them. Something like this will work::
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.. _special encoder: http://svn.red-bean.com/bob/simplejson/tags/simplejson-1.7/docs/index.html
|
||||
|
||||
.. _topics-serialization-natural-keys:
|
||||
|
||||
Natural keys
|
||||
------------
|
||||
|
||||
The default serialization strategy for foreign keys and many-to-many
|
||||
relations is to serialize the value of the primary key(s) of the
|
||||
objects in the relation. This strategy works well for most types of
|
||||
object, but it can cause difficulty in some circumstances.
|
||||
|
||||
Consider the case of a list of objects that have foreign key on
|
||||
:class:`ContentType`. If you're going to serialize an object that
|
||||
refers to a content type, you need to have a way to refer to that
|
||||
content type. Content Types are automatically created by Django as
|
||||
part of the database synchronization process, so you don't need to
|
||||
include content types in a fixture or other serialized data. As a
|
||||
result, the primary key of any given content type isn't easy to
|
||||
predict - it will depend on how and when :djadmin:`syncdb` was
|
||||
executed to create the content types.
|
||||
|
||||
There is also the matter of convenience. An integer id isn't always
|
||||
the most convenient way to refer to an object; sometimes, a
|
||||
more natural reference would be helpful.
|
||||
|
||||
Deserialization of natural keys
|
||||
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
It is for these reasons that Django provides `natural keys`. A natural
|
||||
key is a tuple of values that can be used to uniquely identify an
|
||||
object instance without using the primary key value.
|
||||
|
||||
Consider the following two models::
|
||||
|
||||
from django.db import models
|
||||
|
||||
class Person(models.Model):
|
||||
first_name = models.CharField(max_length=100)
|
||||
last_name = models.CharField(max_length=100)
|
||||
|
||||
birthdate = models.DateField()
|
||||
|
||||
class Book(models.Model):
|
||||
name = models.CharField(max_length=100)
|
||||
author = models.ForeignKey(Person)
|
||||
|
||||
Ordinarily, serialized data for ``Book`` would use an integer to refer to
|
||||
the author. For example, in JSON, a Book might be serialized as::
|
||||
|
||||
...
|
||||
{
|
||||
"pk": 1,
|
||||
"model": "store.book",
|
||||
"fields": {
|
||||
"name": "Mostly Harmless",
|
||||
"author": 42
|
||||
}
|
||||
}
|
||||
...
|
||||
|
||||
This isn't a particularly natural way to refer to an author. It
|
||||
requires that you know the primary key value for the author; it also
|
||||
requires that this primary key value is stable and predictable.
|
||||
|
||||
However, if we add natural key handling to Person, the fixture becomes
|
||||
much more humane. To add natural key handling, you define a default
|
||||
Manager for Person with a ``get_by_natural_key()`` method. In the case
|
||||
of a Person, a good natural key might be the pair of first and last
|
||||
name::
|
||||
|
||||
from django.db import models
|
||||
|
||||
class PersonManager(models.Manager):
|
||||
def get_by_natural_key(self, first_name, last_name):
|
||||
return self.filter(first_name=first_name, last_name=last_name)
|
||||
|
||||
class Person(models.Model):
|
||||
objects = PersonManager()
|
||||
|
||||
first_name = models.CharField(max_length=100)
|
||||
last_name = models.CharField(max_length=100)
|
||||
|
||||
birthdate = models.DateField()
|
||||
|
||||
Now books can use that natural key to refer to ``Person`` objects::
|
||||
|
||||
...
|
||||
{
|
||||
"pk": 1,
|
||||
"model": "store.book",
|
||||
"fields": {
|
||||
"name": "Mostly Harmless",
|
||||
"author": ["Douglas", "Adams"]
|
||||
}
|
||||
}
|
||||
...
|
||||
|
||||
When you try to load this serialized data, Django will use the
|
||||
``get_by_natural_key()`` method to resolve ``["Douglas", "Adams"]``
|
||||
into the primary key of an actual ``Person`` object.
|
||||
|
||||
Serialization of natural keys
|
||||
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
So how do you get Django to emit a natural key when serializing an object?
|
||||
Firstly, you need to add another method -- this time to the model itself::
|
||||
|
||||
class Person(models.Model):
|
||||
objects = PersonManager()
|
||||
|
||||
first_name = models.CharField(max_length=100)
|
||||
last_name = models.CharField(max_length=100)
|
||||
|
||||
birthdate = models.DateField()
|
||||
|
||||
def natural_key(self):
|
||||
return (self.first_name, self.last_name)
|
||||
|
||||
Then, when you call ``serializers.serialize()``, you provide a
|
||||
``use_natural_keys=True`` argument::
|
||||
|
||||
>>> serializers.serialize([book1, book2], format='json', indent=2, use_natural_keys=True)
|
||||
|
||||
When ``use_natural_keys=True`` is specified, Django will use the
|
||||
``natural_key()`` method to serialize any reference to objects of the
|
||||
type that defines the method.
|
||||
|
||||
If you are using :djadmin:`dumpdata` to generate serialized data, you
|
||||
use the `--natural` command line flag to generate natural keys.
|
||||
|
||||
.. note::
|
||||
|
||||
You don't need to define both ``natural_key()`` and
|
||||
``get_by_natural_key()``. If you don't want Django to output
|
||||
natural keys during serialization, but you want to retain the
|
||||
ability to load natural keys, then you can opt to not implement
|
||||
the ``natural_key()`` method.
|
||||
|
||||
Conversely, if (for some strange reason) you want Django to output
|
||||
natural keys during serialization, but *not* be able to load those
|
||||
key values, just don't define the ``get_by_natural_key()`` method.
|
||||
|
||||
Dependencies during serialization
|
||||
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
Since natural keys rely on database lookups to resolve references, it
|
||||
is important that data exists before it is referenced. You can't make
|
||||
a `forward reference` with natural keys - the data you are referencing
|
||||
must exist before you include a natural key reference to that data.
|
||||
|
||||
To accommodate this limitation, calls to :djadmin:`dumpdata` that use
|
||||
the :djadminopt:`--natural` optionwill serialize any model with a
|
||||
``natural_key()`` method before it serializes normal key objects.
|
||||
|
||||
However, this may not always be enough. If your natural key refers to
|
||||
another object (by using a foreign key or natural key to another object
|
||||
as part of a natural key), then you need to be able to ensure that
|
||||
the objects on which a natural key depends occur in the serialized data
|
||||
before the natural key requires them.
|
||||
|
||||
To control this ordering, you can define dependencies on your
|
||||
``natural_key()`` methods. You do this by setting a ``dependencies``
|
||||
attribute on the ``natural_key()`` method itself.
|
||||
|
||||
For example, consider the ``Permission`` model in ``contrib.auth``.
|
||||
The following is a simplified version of the ``Permission`` model::
|
||||
|
||||
class Permission(models.Model):
|
||||
name = models.CharField(max_length=50)
|
||||
content_type = models.ForeignKey(ContentType)
|
||||
codename = models.CharField(max_length=100)
|
||||
# ...
|
||||
def natural_key(self):
|
||||
return (self.codename,) + self.content_type.natural_key()
|
||||
|
||||
The natural key for a ``Permission`` is a combination of the codename for the
|
||||
``Permission``, and the ``ContentType`` to which the ``Permission`` applies. This means
|
||||
that ``ContentType`` must be serialized before ``Permission``. To define this
|
||||
dependency, we add one extra line::
|
||||
|
||||
class Permission(models.Model):
|
||||
# ...
|
||||
def natural_key(self):
|
||||
return (self.codename,) + self.content_type.natural_key()
|
||||
natural_key.dependencies = ['contenttypes.contenttype']
|
||||
|
||||
This definition ensures that ``ContentType`` models are serialized before
|
||||
``Permission`` models. In turn, any object referencing ``Permission`` will
|
||||
be serialized after both ``ContentType`` and ``Permission``.
|
||||
|
|
|
|||
|
|
@ -0,0 +1,41 @@
|
|||
[
|
||||
{
|
||||
"pk": "1",
|
||||
"model": "fixtures.tag",
|
||||
"fields": {
|
||||
"name": "copyright",
|
||||
"tagged_type": ["fixtures", "article"],
|
||||
"tagged_id": "3"
|
||||
}
|
||||
},
|
||||
{
|
||||
"pk": "2",
|
||||
"model": "fixtures.tag",
|
||||
"fields": {
|
||||
"name": "law",
|
||||
"tagged_type": ["fixtures", "article"],
|
||||
"tagged_id": "3"
|
||||
}
|
||||
},
|
||||
{
|
||||
"pk": "1",
|
||||
"model": "fixtures.person",
|
||||
"fields": {
|
||||
"name": "Django Reinhardt"
|
||||
}
|
||||
},
|
||||
{
|
||||
"pk": "2",
|
||||
"model": "fixtures.person",
|
||||
"fields": {
|
||||
"name": "Stephane Grappelli"
|
||||
}
|
||||
},
|
||||
{
|
||||
"pk": "3",
|
||||
"model": "fixtures.person",
|
||||
"fields": {
|
||||
"name": "Prince"
|
||||
}
|
||||
}
|
||||
]
|
||||
|
|
@ -0,0 +1,27 @@
|
|||
<?xml version="1.0" encoding="utf-8"?>
|
||||
<django-objects version="1.0">
|
||||
<object pk="2" model="fixtures.tag">
|
||||
<field type="CharField" name="name">legal</field>
|
||||
<field to="contenttypes.contenttype" name="tagged_type" rel="ManyToOneRel">
|
||||
<natural>fixtures</natural>
|
||||
<natural>article</natural>
|
||||
</field>
|
||||
<field type="PositiveIntegerField" name="tagged_id">3</field>
|
||||
</object>
|
||||
<object pk="3" model="fixtures.tag">
|
||||
<field type="CharField" name="name">django</field>
|
||||
<field to="contenttypes.contenttype" name="tagged_type" rel="ManyToOneRel">
|
||||
<natural>fixtures</natural>
|
||||
<natural>article</natural>
|
||||
</field>
|
||||
<field type="PositiveIntegerField" name="tagged_id">4</field>
|
||||
</object>
|
||||
<object pk="4" model="fixtures.tag">
|
||||
<field type="CharField" name="name">world domination</field>
|
||||
<field to="contenttypes.contenttype" name="tagged_type" rel="ManyToOneRel">
|
||||
<natural>fixtures</natural>
|
||||
<natural>article</natural>
|
||||
</field>
|
||||
<field type="PositiveIntegerField" name="tagged_id">4</field>
|
||||
</object>
|
||||
</django-objects>
|
||||
|
|
@ -0,0 +1,32 @@
|
|||
[
|
||||
{
|
||||
"pk": "1",
|
||||
"model": "fixtures.visa",
|
||||
"fields": {
|
||||
"person": ["Django Reinhardt"],
|
||||
"permissions": [
|
||||
["add_user", "auth", "user"],
|
||||
["change_user", "auth", "user"],
|
||||
["delete_user", "auth", "user"]
|
||||
]
|
||||
}
|
||||
},
|
||||
{
|
||||
"pk": "2",
|
||||
"model": "fixtures.visa",
|
||||
"fields": {
|
||||
"person": ["Stephane Grappelli"],
|
||||
"permissions": [
|
||||
["add_user", "auth", "user"]
|
||||
]
|
||||
}
|
||||
},
|
||||
{
|
||||
"pk": "3",
|
||||
"model": "fixtures.visa",
|
||||
"fields": {
|
||||
"person": ["Prince"],
|
||||
"permissions": []
|
||||
}
|
||||
}
|
||||
]
|
||||
|
|
@ -0,0 +1,48 @@
|
|||
<?xml version="1.0" encoding="utf-8"?>
|
||||
<django-objects version="1.0">
|
||||
<object pk="2" model="fixtures.visa">
|
||||
<field type="CharField" name="person">
|
||||
<natural>Stephane Grappelli</natural>
|
||||
</field>
|
||||
<field to="auth.permission" name="permissions" rel="ManyToManyRel">
|
||||
<object>
|
||||
<natural>add_user</natural>
|
||||
<natural>auth</natural>
|
||||
<natural>user</natural>
|
||||
</object>
|
||||
<object>
|
||||
<natural>delete_user</natural>
|
||||
<natural>auth</natural>
|
||||
<natural>user</natural>
|
||||
</object>
|
||||
</field>
|
||||
</object>
|
||||
<object pk="3" model="fixtures.person">
|
||||
<field type="CharField" name="name">
|
||||
<natural>Artist formerly known as "Prince"</natural>
|
||||
</field>
|
||||
</object>
|
||||
<object pk="3" model="fixtures.visa">
|
||||
<field type="CharField" name="person">
|
||||
<natural>Artist formerly known as "Prince"</natural>
|
||||
</field>
|
||||
<field to="auth.permission" name="permissions" rel="ManyToManyRel">
|
||||
<object>
|
||||
<natural>change_user</natural>
|
||||
<natural>auth</natural>
|
||||
<natural>user</natural>
|
||||
</object>
|
||||
</field>
|
||||
</object>
|
||||
<object pk="1" model="fixtures.book">
|
||||
<field type="CharField" name="name">Music for all ages</field>
|
||||
<field to="fixtures.person" name="authors" rel="ManyToManyRel">
|
||||
<object>
|
||||
<natural>Django Reinhardt</natural>
|
||||
</object>
|
||||
<object>
|
||||
<natural>Artist formerly known as "Prince"</natural>
|
||||
</object>
|
||||
</field>
|
||||
</object>
|
||||
</django-objects>
|
||||
|
|
@ -8,6 +8,9 @@ in the application directory, on in one of the directories named in the
|
|||
``FIXTURE_DIRS`` setting.
|
||||
"""
|
||||
|
||||
from django.contrib.auth.models import Permission
|
||||
from django.contrib.contenttypes import generic
|
||||
from django.contrib.contenttypes.models import ContentType
|
||||
from django.db import models
|
||||
from django.conf import settings
|
||||
|
||||
|
|
@ -31,6 +34,62 @@ class Article(models.Model):
|
|||
class Meta:
|
||||
ordering = ('-pub_date', 'headline')
|
||||
|
||||
class Blog(models.Model):
|
||||
name = models.CharField(max_length=100)
|
||||
featured = models.ForeignKey(Article, related_name='fixtures_featured_set')
|
||||
articles = models.ManyToManyField(Article, blank=True,
|
||||
related_name='fixtures_articles_set')
|
||||
|
||||
def __unicode__(self):
|
||||
return self.name
|
||||
|
||||
|
||||
class Tag(models.Model):
|
||||
name = models.CharField(max_length=100)
|
||||
tagged_type = models.ForeignKey(ContentType, related_name="fixtures_tag_set")
|
||||
tagged_id = models.PositiveIntegerField(default=0)
|
||||
tagged = generic.GenericForeignKey(ct_field='tagged_type',
|
||||
fk_field='tagged_id')
|
||||
|
||||
def __unicode__(self):
|
||||
return '<%s: %s> tagged "%s"' % (self.tagged.__class__.__name__,
|
||||
self.tagged, self.name)
|
||||
|
||||
class PersonManager(models.Manager):
|
||||
def get_by_natural_key(self, name):
|
||||
return self.get(name=name)
|
||||
|
||||
class Person(models.Model):
|
||||
objects = PersonManager()
|
||||
name = models.CharField(max_length=100)
|
||||
def __unicode__(self):
|
||||
return self.name
|
||||
|
||||
class Meta:
|
||||
ordering = ('name',)
|
||||
|
||||
def natural_key(self):
|
||||
return (self.name,)
|
||||
|
||||
class Visa(models.Model):
|
||||
person = models.ForeignKey(Person)
|
||||
permissions = models.ManyToManyField(Permission, blank=True)
|
||||
|
||||
def __unicode__(self):
|
||||
return '%s %s' % (self.person.name,
|
||||
', '.join(p.name for p in self.permissions.all()))
|
||||
|
||||
class Book(models.Model):
|
||||
name = models.CharField(max_length=100)
|
||||
authors = models.ManyToManyField(Person)
|
||||
|
||||
def __unicode__(self):
|
||||
return '%s by %s' % (self.name,
|
||||
' and '.join(a.name for a in self.authors.all()))
|
||||
|
||||
class Meta:
|
||||
ordering = ('name',)
|
||||
|
||||
__test__ = {'API_TESTS': """
|
||||
>>> from django.core import management
|
||||
>>> from django.db.models import get_app
|
||||
|
|
@ -90,12 +149,53 @@ __test__ = {'API_TESTS': """
|
|||
>>> Article.objects.all()
|
||||
[<Article: XML identified as leading cause of cancer>, <Article: Django conquers world!>, <Article: Copyright is fine the way it is>, <Article: Poker on TV is great!>, <Article: Python program becomes self aware>]
|
||||
|
||||
# Load fixture 6, JSON file with dynamic ContentType fields. Testing ManyToOne.
|
||||
>>> management.call_command('loaddata', 'fixture6.json', verbosity=0)
|
||||
>>> Tag.objects.all()
|
||||
[<Tag: <Article: Copyright is fine the way it is> tagged "copyright">, <Tag: <Article: Copyright is fine the way it is> tagged "law">]
|
||||
|
||||
# Load fixture 7, XML file with dynamic ContentType fields. Testing ManyToOne.
|
||||
>>> management.call_command('loaddata', 'fixture7.xml', verbosity=0)
|
||||
>>> Tag.objects.all()
|
||||
[<Tag: <Article: Copyright is fine the way it is> tagged "copyright">, <Tag: <Article: Copyright is fine the way it is> tagged "legal">, <Tag: <Article: Django conquers world!> tagged "django">, <Tag: <Article: Django conquers world!> tagged "world domination">]
|
||||
|
||||
# Load fixture 8, JSON file with dynamic Permission fields. Testing ManyToMany.
|
||||
>>> management.call_command('loaddata', 'fixture8.json', verbosity=0)
|
||||
>>> Visa.objects.all()
|
||||
[<Visa: Django Reinhardt Can add user, Can change user, Can delete user>, <Visa: Stephane Grappelli Can add user>, <Visa: Prince >]
|
||||
|
||||
# Load fixture 9, XML file with dynamic Permission fields. Testing ManyToMany.
|
||||
>>> management.call_command('loaddata', 'fixture9.xml', verbosity=0)
|
||||
>>> Visa.objects.all()
|
||||
[<Visa: Django Reinhardt Can add user, Can change user, Can delete user>, <Visa: Stephane Grappelli Can add user, Can delete user>, <Visa: Artist formerly known as "Prince" Can change user>]
|
||||
|
||||
>>> Book.objects.all()
|
||||
[<Book: Music for all ages by Artist formerly known as "Prince" and Django Reinhardt>]
|
||||
|
||||
# Load a fixture that doesn't exist
|
||||
>>> management.call_command('loaddata', 'unknown.json', verbosity=0)
|
||||
|
||||
# object list is unaffected
|
||||
>>> Article.objects.all()
|
||||
[<Article: XML identified as leading cause of cancer>, <Article: Django conquers world!>, <Article: Copyright is fine the way it is>, <Article: Poker on TV is great!>, <Article: Python program becomes self aware>]
|
||||
|
||||
# By default, you get raw keys on dumpdata
|
||||
>>> management.call_command('dumpdata', 'fixtures.book', format='json')
|
||||
[{"pk": 1, "model": "fixtures.book", "fields": {"name": "Music for all ages", "authors": [3, 1]}}]
|
||||
|
||||
# But you can get natural keys if you ask for them and they are available
|
||||
>>> management.call_command('dumpdata', 'fixtures.book', format='json', use_natural_keys=True)
|
||||
[{"pk": 1, "model": "fixtures.book", "fields": {"name": "Music for all ages", "authors": [["Artist formerly known as \\"Prince\\""], ["Django Reinhardt"]]}}]
|
||||
|
||||
# Dump the current contents of the database as a JSON fixture
|
||||
>>> management.call_command('dumpdata', 'fixtures', format='json', use_natural_keys=True)
|
||||
[{"pk": 1, "model": "fixtures.category", "fields": {"description": "Latest news stories", "title": "News Stories"}}, {"pk": 5, "model": "fixtures.article", "fields": {"headline": "XML identified as leading cause of cancer", "pub_date": "2006-06-16 16:00:00"}}, {"pk": 4, "model": "fixtures.article", "fields": {"headline": "Django conquers world!", "pub_date": "2006-06-16 15:00:00"}}, {"pk": 3, "model": "fixtures.article", "fields": {"headline": "Copyright is fine the way it is", "pub_date": "2006-06-16 14:00:00"}}, {"pk": 2, "model": "fixtures.article", "fields": {"headline": "Poker on TV is great!", "pub_date": "2006-06-16 11:00:00"}}, {"pk": 1, "model": "fixtures.article", "fields": {"headline": "Python program becomes self aware", "pub_date": "2006-06-16 11:00:00"}}, {"pk": 1, "model": "fixtures.tag", "fields": {"tagged_type": ["fixtures", "article"], "name": "copyright", "tagged_id": 3}}, {"pk": 2, "model": "fixtures.tag", "fields": {"tagged_type": ["fixtures", "article"], "name": "legal", "tagged_id": 3}}, {"pk": 3, "model": "fixtures.tag", "fields": {"tagged_type": ["fixtures", "article"], "name": "django", "tagged_id": 4}}, {"pk": 4, "model": "fixtures.tag", "fields": {"tagged_type": ["fixtures", "article"], "name": "world domination", "tagged_id": 4}}, {"pk": 3, "model": "fixtures.person", "fields": {"name": "Artist formerly known as \\"Prince\\""}}, {"pk": 1, "model": "fixtures.person", "fields": {"name": "Django Reinhardt"}}, {"pk": 2, "model": "fixtures.person", "fields": {"name": "Stephane Grappelli"}}, {"pk": 1, "model": "fixtures.visa", "fields": {"person": ["Django Reinhardt"], "permissions": [["add_user", "auth", "user"], ["change_user", "auth", "user"], ["delete_user", "auth", "user"]]}}, {"pk": 2, "model": "fixtures.visa", "fields": {"person": ["Stephane Grappelli"], "permissions": [["add_user", "auth", "user"], ["delete_user", "auth", "user"]]}}, {"pk": 3, "model": "fixtures.visa", "fields": {"person": ["Artist formerly known as \\"Prince\\""], "permissions": [["change_user", "auth", "user"]]}}, {"pk": 1, "model": "fixtures.book", "fields": {"name": "Music for all ages", "authors": [["Artist formerly known as \\"Prince\\""], ["Django Reinhardt"]]}}]
|
||||
|
||||
# Dump the current contents of the database as an XML fixture
|
||||
>>> management.call_command('dumpdata', 'fixtures', format='xml', use_natural_keys=True)
|
||||
<?xml version="1.0" encoding="utf-8"?>
|
||||
<django-objects version="1.0"><object pk="1" model="fixtures.category"><field type="CharField" name="title">News Stories</field><field type="TextField" name="description">Latest news stories</field></object><object pk="5" model="fixtures.article"><field type="CharField" name="headline">XML identified as leading cause of cancer</field><field type="DateTimeField" name="pub_date">2006-06-16 16:00:00</field></object><object pk="4" model="fixtures.article"><field type="CharField" name="headline">Django conquers world!</field><field type="DateTimeField" name="pub_date">2006-06-16 15:00:00</field></object><object pk="3" model="fixtures.article"><field type="CharField" name="headline">Copyright is fine the way it is</field><field type="DateTimeField" name="pub_date">2006-06-16 14:00:00</field></object><object pk="2" model="fixtures.article"><field type="CharField" name="headline">Poker on TV is great!</field><field type="DateTimeField" name="pub_date">2006-06-16 11:00:00</field></object><object pk="1" model="fixtures.article"><field type="CharField" name="headline">Python program becomes self aware</field><field type="DateTimeField" name="pub_date">2006-06-16 11:00:00</field></object><object pk="1" model="fixtures.tag"><field type="CharField" name="name">copyright</field><field to="contenttypes.contenttype" name="tagged_type" rel="ManyToOneRel"><natural>fixtures</natural><natural>article</natural></field><field type="PositiveIntegerField" name="tagged_id">3</field></object><object pk="2" model="fixtures.tag"><field type="CharField" name="name">legal</field><field to="contenttypes.contenttype" name="tagged_type" rel="ManyToOneRel"><natural>fixtures</natural><natural>article</natural></field><field type="PositiveIntegerField" name="tagged_id">3</field></object><object pk="3" model="fixtures.tag"><field type="CharField" name="name">django</field><field to="contenttypes.contenttype" name="tagged_type" rel="ManyToOneRel"><natural>fixtures</natural><natural>article</natural></field><field type="PositiveIntegerField" name="tagged_id">4</field></object><object pk="4" model="fixtures.tag"><field type="CharField" name="name">world domination</field><field to="contenttypes.contenttype" name="tagged_type" rel="ManyToOneRel"><natural>fixtures</natural><natural>article</natural></field><field type="PositiveIntegerField" name="tagged_id">4</field></object><object pk="3" model="fixtures.person"><field type="CharField" name="name">Artist formerly known as "Prince"</field></object><object pk="1" model="fixtures.person"><field type="CharField" name="name">Django Reinhardt</field></object><object pk="2" model="fixtures.person"><field type="CharField" name="name">Stephane Grappelli</field></object><object pk="1" model="fixtures.visa"><field to="fixtures.person" name="person" rel="ManyToOneRel"><natural>Django Reinhardt</natural></field><field to="auth.permission" name="permissions" rel="ManyToManyRel"><object><natural>add_user</natural><natural>auth</natural><natural>user</natural></object><object><natural>change_user</natural><natural>auth</natural><natural>user</natural></object><object><natural>delete_user</natural><natural>auth</natural><natural>user</natural></object></field></object><object pk="2" model="fixtures.visa"><field to="fixtures.person" name="person" rel="ManyToOneRel"><natural>Stephane Grappelli</natural></field><field to="auth.permission" name="permissions" rel="ManyToManyRel"><object><natural>add_user</natural><natural>auth</natural><natural>user</natural></object><object><natural>delete_user</natural><natural>auth</natural><natural>user</natural></object></field></object><object pk="3" model="fixtures.visa"><field to="fixtures.person" name="person" rel="ManyToOneRel"><natural>Artist formerly known as "Prince"</natural></field><field to="auth.permission" name="permissions" rel="ManyToManyRel"><object><natural>change_user</natural><natural>auth</natural><natural>user</natural></object></field></object><object pk="1" model="fixtures.book"><field type="CharField" name="name">Music for all ages</field><field to="fixtures.person" name="authors" rel="ManyToManyRel"><object><natural>Artist formerly known as "Prince"</natural></object><object><natural>Django Reinhardt</natural></object></field></object></django-objects>
|
||||
|
||||
"""}
|
||||
|
||||
# Database flushing does not work on MySQL with the default storage engine
|
||||
|
|
@ -159,6 +259,25 @@ Multiple fixtures named 'fixture2' in '...fixtures'. Aborting.
|
|||
>>> management.call_command('loaddata', 'fixture5', verbosity=0) # doctest: +ELLIPSIS
|
||||
Multiple fixtures named 'fixture5' in '...fixtures'. Aborting.
|
||||
|
||||
>>> management.call_command('flush', verbosity=0, interactive=False)
|
||||
|
||||
# Load back in fixture 1, we need the articles from it
|
||||
>>> management.call_command('loaddata', 'fixture1', verbosity=0)
|
||||
|
||||
# Try to load fixture 6 using format discovery
|
||||
>>> management.call_command('loaddata', 'fixture6', verbosity=0)
|
||||
>>> Tag.objects.all()
|
||||
[<Tag: <Article: Time to reform copyright> tagged "copyright">, <Tag: <Article: Time to reform copyright> tagged "law">]
|
||||
|
||||
# Dump the current contents of the database as a JSON fixture
|
||||
>>> management.call_command('dumpdata', 'fixtures', format='json', use_natural_keys=True)
|
||||
[{"pk": 1, "model": "fixtures.category", "fields": {"description": "Latest news stories", "title": "News Stories"}}, {"pk": 3, "model": "fixtures.article", "fields": {"headline": "Time to reform copyright", "pub_date": "2006-06-16 13:00:00"}}, {"pk": 2, "model": "fixtures.article", "fields": {"headline": "Poker has no place on ESPN", "pub_date": "2006-06-16 12:00:00"}}, {"pk": 1, "model": "fixtures.article", "fields": {"headline": "Python program becomes self aware", "pub_date": "2006-06-16 11:00:00"}}, {"pk": 1, "model": "fixtures.tag", "fields": {"tagged_type": ["fixtures", "article"], "name": "copyright", "tagged_id": 3}}, {"pk": 2, "model": "fixtures.tag", "fields": {"tagged_type": ["fixtures", "article"], "name": "law", "tagged_id": 3}}, {"pk": 1, "model": "fixtures.person", "fields": {"name": "Django Reinhardt"}}, {"pk": 3, "model": "fixtures.person", "fields": {"name": "Prince"}}, {"pk": 2, "model": "fixtures.person", "fields": {"name": "Stephane Grappelli"}}]
|
||||
|
||||
# Dump the current contents of the database as an XML fixture
|
||||
>>> management.call_command('dumpdata', 'fixtures', format='xml', use_natural_keys=True)
|
||||
<?xml version="1.0" encoding="utf-8"?>
|
||||
<django-objects version="1.0"><object pk="1" model="fixtures.category"><field type="CharField" name="title">News Stories</field><field type="TextField" name="description">Latest news stories</field></object><object pk="3" model="fixtures.article"><field type="CharField" name="headline">Time to reform copyright</field><field type="DateTimeField" name="pub_date">2006-06-16 13:00:00</field></object><object pk="2" model="fixtures.article"><field type="CharField" name="headline">Poker has no place on ESPN</field><field type="DateTimeField" name="pub_date">2006-06-16 12:00:00</field></object><object pk="1" model="fixtures.article"><field type="CharField" name="headline">Python program becomes self aware</field><field type="DateTimeField" name="pub_date">2006-06-16 11:00:00</field></object><object pk="1" model="fixtures.tag"><field type="CharField" name="name">copyright</field><field to="contenttypes.contenttype" name="tagged_type" rel="ManyToOneRel"><natural>fixtures</natural><natural>article</natural></field><field type="PositiveIntegerField" name="tagged_id">3</field></object><object pk="2" model="fixtures.tag"><field type="CharField" name="name">law</field><field to="contenttypes.contenttype" name="tagged_type" rel="ManyToOneRel"><natural>fixtures</natural><natural>article</natural></field><field type="PositiveIntegerField" name="tagged_id">3</field></object><object pk="1" model="fixtures.person"><field type="CharField" name="name">Django Reinhardt</field></object><object pk="3" model="fixtures.person"><field type="CharField" name="name">Prince</field></object><object pk="2" model="fixtures.person"><field type="CharField" name="name">Stephane Grappelli</field></object></django-objects>
|
||||
|
||||
"""
|
||||
|
||||
from django.test import TestCase
|
||||
|
|
|
|||
|
|
@ -0,0 +1,32 @@
|
|||
[
|
||||
{
|
||||
"pk": "4",
|
||||
"model": "fixtures_regress.person",
|
||||
"fields": {
|
||||
"name": "Neal Stephenson"
|
||||
}
|
||||
},
|
||||
{
|
||||
"pk": "2",
|
||||
"model": "fixtures_regress.store",
|
||||
"fields": {
|
||||
"name": "Amazon"
|
||||
}
|
||||
},
|
||||
{
|
||||
"pk": "3",
|
||||
"model": "fixtures_regress.store",
|
||||
"fields": {
|
||||
"name": "Borders"
|
||||
}
|
||||
},
|
||||
{
|
||||
"pk": 1,
|
||||
"model": "fixtures_regress.book",
|
||||
"fields": {
|
||||
"name": "Cryptonomicon",
|
||||
"author": ["Neal Stephenson"],
|
||||
"stores": [["Amazon"], ["Borders"]]
|
||||
}
|
||||
}
|
||||
]
|
||||
|
|
@ -0,0 +1,25 @@
|
|||
[
|
||||
{
|
||||
"pk": 12,
|
||||
"model": "fixtures_regress.person",
|
||||
"fields": {
|
||||
"name": "Greg Egan"
|
||||
}
|
||||
},
|
||||
{
|
||||
"pk": 11,
|
||||
"model": "fixtures_regress.store",
|
||||
"fields": {
|
||||
"name": "Angus and Robertson"
|
||||
}
|
||||
},
|
||||
{
|
||||
"pk": 10,
|
||||
"model": "fixtures_regress.book",
|
||||
"fields": {
|
||||
"name": "Permutation City",
|
||||
"author": 12,
|
||||
"stores": [11]
|
||||
}
|
||||
}
|
||||
]
|
||||
|
|
@ -0,0 +1,16 @@
|
|||
<?xml version="1.0" encoding="utf-8"?>
|
||||
<django-objects version="1.0">
|
||||
<object pk="22" model="fixtures_regress.person">
|
||||
<field type="CharField" name="name">Orson Scott Card</field>
|
||||
</object>
|
||||
<object pk="21" model="fixtures_regress.store">
|
||||
<field type="CharField" name="name">Collins Bookstore</field>
|
||||
</object>
|
||||
<object pk="20" model="fixtures_regress.book">
|
||||
<field type="CharField" name="name">Ender's Game</field>
|
||||
<field to="fixtures_regress.person" name="author" rel="ManyToOneRel">22</field>
|
||||
<field to="fixtures_regress.store" name="stores" rel="ManyToManyRel">
|
||||
<object pk="21"/>
|
||||
</field>
|
||||
</object>
|
||||
</django-objects>
|
||||
|
|
@ -13,7 +13,7 @@ class Animal(models.Model):
|
|||
specimens = models.Manager()
|
||||
|
||||
def __unicode__(self):
|
||||
return self.common_name
|
||||
return self.name
|
||||
|
||||
def animal_pre_save_check(signal, sender, instance, **kwargs):
|
||||
"A signal that is used to check the type of data loaded from fixtures"
|
||||
|
|
@ -69,10 +69,66 @@ class Article(models.Model):
|
|||
class Widget(models.Model):
|
||||
name = models.CharField(max_length=255)
|
||||
|
||||
class Meta:
|
||||
ordering = ('name',)
|
||||
|
||||
def __unicode__(self):
|
||||
return self.name
|
||||
|
||||
class WidgetProxy(Widget):
|
||||
class Meta:
|
||||
proxy = True
|
||||
|
||||
# Check for forward references in FKs and M2Ms with natural keys
|
||||
|
||||
class TestManager(models.Manager):
|
||||
def get_by_natural_key(self, key):
|
||||
return self.get(name=key)
|
||||
|
||||
class Store(models.Model):
|
||||
objects = TestManager()
|
||||
name = models.CharField(max_length=255)
|
||||
|
||||
class Meta:
|
||||
ordering = ('name',)
|
||||
|
||||
def __unicode__(self):
|
||||
return self.name
|
||||
|
||||
def natural_key(self):
|
||||
return (self.name,)
|
||||
|
||||
class Person(models.Model):
|
||||
objects = TestManager()
|
||||
name = models.CharField(max_length=255)
|
||||
|
||||
class Meta:
|
||||
ordering = ('name',)
|
||||
|
||||
def __unicode__(self):
|
||||
return self.name
|
||||
|
||||
# Person doesn't actually have a dependency on store, but we need to define
|
||||
# one to test the behaviour of the dependency resolution algorithm.
|
||||
def natural_key(self):
|
||||
return (self.name,)
|
||||
natural_key.dependencies = ['fixtures_regress.store']
|
||||
|
||||
class Book(models.Model):
|
||||
name = models.CharField(max_length=255)
|
||||
author = models.ForeignKey(Person)
|
||||
stores = models.ManyToManyField(Store)
|
||||
|
||||
class Meta:
|
||||
ordering = ('name',)
|
||||
|
||||
def __unicode__(self):
|
||||
return u'%s by %s (available at %s)' % (
|
||||
self.name,
|
||||
self.author.name,
|
||||
', '.join(s.name for s in self.stores.all())
|
||||
)
|
||||
|
||||
__test__ = {'API_TESTS':"""
|
||||
>>> from django.core import management
|
||||
|
||||
|
|
@ -192,4 +248,121 @@ Weight = 1.2 (<type 'float'>)
|
|||
>>> management.call_command('dumpdata', 'fixtures_regress', format='json')
|
||||
[{"pk": 1, "model": "fixtures_regress.widget", "fields": {"name": "grommet"}}]
|
||||
|
||||
###############################################
|
||||
# Check that natural key requirements are taken into account
|
||||
# when serializing models
|
||||
>>> management.call_command('loaddata', 'forward_ref_lookup.json', verbosity=0)
|
||||
|
||||
>>> management.call_command('dumpdata', 'fixtures_regress.book', 'fixtures_regress.person', 'fixtures_regress.store', verbosity=0, use_natural_keys=True)
|
||||
[{"pk": 2, "model": "fixtures_regress.store", "fields": {"name": "Amazon"}}, {"pk": 3, "model": "fixtures_regress.store", "fields": {"name": "Borders"}}, {"pk": 4, "model": "fixtures_regress.person", "fields": {"name": "Neal Stephenson"}}, {"pk": 1, "model": "fixtures_regress.book", "fields": {"stores": [["Amazon"], ["Borders"]], "name": "Cryptonomicon", "author": ["Neal Stephenson"]}}]
|
||||
|
||||
# Now lets check the dependency sorting explicitly
|
||||
|
||||
# First Some models with pathological circular dependencies
|
||||
>>> class Circle1(models.Model):
|
||||
... name = models.CharField(max_length=255)
|
||||
... def natural_key(self):
|
||||
... return self.name
|
||||
... natural_key.dependencies = ['fixtures_regress.circle2']
|
||||
|
||||
>>> class Circle2(models.Model):
|
||||
... name = models.CharField(max_length=255)
|
||||
... def natural_key(self):
|
||||
... return self.name
|
||||
... natural_key.dependencies = ['fixtures_regress.circle1']
|
||||
|
||||
>>> class Circle3(models.Model):
|
||||
... name = models.CharField(max_length=255)
|
||||
... def natural_key(self):
|
||||
... return self.name
|
||||
... natural_key.dependencies = ['fixtures_regress.circle3']
|
||||
|
||||
>>> class Circle4(models.Model):
|
||||
... name = models.CharField(max_length=255)
|
||||
... def natural_key(self):
|
||||
... return self.name
|
||||
... natural_key.dependencies = ['fixtures_regress.circle5']
|
||||
|
||||
>>> class Circle5(models.Model):
|
||||
... name = models.CharField(max_length=255)
|
||||
... def natural_key(self):
|
||||
... return self.name
|
||||
... natural_key.dependencies = ['fixtures_regress.circle6']
|
||||
|
||||
>>> class Circle6(models.Model):
|
||||
... name = models.CharField(max_length=255)
|
||||
... def natural_key(self):
|
||||
... return self.name
|
||||
... natural_key.dependencies = ['fixtures_regress.circle4']
|
||||
|
||||
>>> class ExternalDependency(models.Model):
|
||||
... name = models.CharField(max_length=255)
|
||||
... def natural_key(self):
|
||||
... return self.name
|
||||
... natural_key.dependencies = ['fixtures_regress.book']
|
||||
|
||||
# It doesn't matter what order you mention the models
|
||||
# Store *must* be serialized before then Person, and both
|
||||
# must be serialized before Book.
|
||||
>>> from django.core.management.commands.dumpdata import sort_dependencies
|
||||
>>> sort_dependencies([('fixtures_regress', [Book, Person, Store])])
|
||||
[<class 'regressiontests.fixtures_regress.models.Store'>, <class 'regressiontests.fixtures_regress.models.Person'>, <class 'regressiontests.fixtures_regress.models.Book'>]
|
||||
|
||||
>>> sort_dependencies([('fixtures_regress', [Book, Store, Person])])
|
||||
[<class 'regressiontests.fixtures_regress.models.Store'>, <class 'regressiontests.fixtures_regress.models.Person'>, <class 'regressiontests.fixtures_regress.models.Book'>]
|
||||
|
||||
>>> sort_dependencies([('fixtures_regress', [Store, Book, Person])])
|
||||
[<class 'regressiontests.fixtures_regress.models.Store'>, <class 'regressiontests.fixtures_regress.models.Person'>, <class 'regressiontests.fixtures_regress.models.Book'>]
|
||||
|
||||
>>> sort_dependencies([('fixtures_regress', [Store, Person, Book])])
|
||||
[<class 'regressiontests.fixtures_regress.models.Store'>, <class 'regressiontests.fixtures_regress.models.Person'>, <class 'regressiontests.fixtures_regress.models.Book'>]
|
||||
|
||||
>>> sort_dependencies([('fixtures_regress', [Person, Book, Store])])
|
||||
[<class 'regressiontests.fixtures_regress.models.Store'>, <class 'regressiontests.fixtures_regress.models.Person'>, <class 'regressiontests.fixtures_regress.models.Book'>]
|
||||
|
||||
>>> sort_dependencies([('fixtures_regress', [Person, Store, Book])])
|
||||
[<class 'regressiontests.fixtures_regress.models.Store'>, <class 'regressiontests.fixtures_regress.models.Person'>, <class 'regressiontests.fixtures_regress.models.Book'>]
|
||||
|
||||
# A dangling dependency - assume the user knows what they are doing.
|
||||
>>> sort_dependencies([('fixtures_regress', [Person, Circle1, Store, Book])])
|
||||
[<class 'regressiontests.fixtures_regress.models.Circle1'>, <class 'regressiontests.fixtures_regress.models.Store'>, <class 'regressiontests.fixtures_regress.models.Person'>, <class 'regressiontests.fixtures_regress.models.Book'>]
|
||||
|
||||
# A tight circular dependency
|
||||
>>> sort_dependencies([('fixtures_regress', [Person, Circle2, Circle1, Store, Book])])
|
||||
Traceback (most recent call last):
|
||||
...
|
||||
CommandError: Can't resolve dependencies for fixtures_regress.Circle1, fixtures_regress.Circle2 in serialized app list.
|
||||
|
||||
>>> sort_dependencies([('fixtures_regress', [Circle1, Book, Circle2])])
|
||||
Traceback (most recent call last):
|
||||
...
|
||||
CommandError: Can't resolve dependencies for fixtures_regress.Circle1, fixtures_regress.Circle2 in serialized app list.
|
||||
|
||||
# A self referential dependency
|
||||
>>> sort_dependencies([('fixtures_regress', [Book, Circle3])])
|
||||
Traceback (most recent call last):
|
||||
...
|
||||
CommandError: Can't resolve dependencies for fixtures_regress.Circle3 in serialized app list.
|
||||
|
||||
# A long circular dependency
|
||||
>>> sort_dependencies([('fixtures_regress', [Person, Circle2, Circle1, Circle3, Store, Book])])
|
||||
Traceback (most recent call last):
|
||||
...
|
||||
CommandError: Can't resolve dependencies for fixtures_regress.Circle1, fixtures_regress.Circle2, fixtures_regress.Circle3 in serialized app list.
|
||||
|
||||
# A dependency on a normal, non-natural-key model
|
||||
>>> sort_dependencies([('fixtures_regress', [Person, ExternalDependency, Book])])
|
||||
[<class 'regressiontests.fixtures_regress.models.Person'>, <class 'regressiontests.fixtures_regress.models.Book'>, <class 'regressiontests.fixtures_regress.models.ExternalDependency'>]
|
||||
|
||||
###############################################
|
||||
# Check that normal primary keys still work
|
||||
# on a model with natural key capabilities
|
||||
|
||||
>>> management.call_command('loaddata', 'non_natural_1.json', verbosity=0)
|
||||
>>> management.call_command('loaddata', 'non_natural_2.xml', verbosity=0)
|
||||
|
||||
>>> Book.objects.all()
|
||||
[<Book: Cryptonomicon by Neal Stephenson (available at Amazon, Borders)>, <Book: Ender's Game by Orson Scott Card (available at Collins Bookstore)>, <Book: Permutation City by Greg Egan (available at Angus and Robertson)>]
|
||||
|
||||
"""}
|
||||
|
||||
|
|
|
|||
Loading…
Reference in New Issue