diff -r b758351d191f -r cc9b7e14412b web/lib/django/core/management/commands/dumpdata.py --- a/web/lib/django/core/management/commands/dumpdata.py Wed May 19 17:43:59 2010 +0200 +++ b/web/lib/django/core/management/commands/dumpdata.py Tue May 25 02:43:45 2010 +0200 @@ -1,6 +1,7 @@ from django.core.exceptions import ImproperlyConfigured from django.core.management.base import BaseCommand, CommandError from django.core import serializers +from django.db import connections, router, DEFAULT_DB_ALIAS from django.utils.datastructures import SortedDict from optparse import make_option @@ -11,24 +12,32 @@ help='Specifies the output serialization format for fixtures.'), make_option('--indent', default=None, dest='indent', type='int', help='Specifies the indent level to use when pretty-printing output'), + make_option('--database', action='store', dest='database', + default=DEFAULT_DB_ALIAS, help='Nominates a specific database to load ' + 'fixtures into. Defaults to the "default" database.'), make_option('-e', '--exclude', dest='exclude',action='append', default=[], help='App to exclude (use multiple --exclude to exclude multiple apps).'), + make_option('-n', '--natural', action='store_true', dest='use_natural_keys', default=False, + help='Use natural keys if they are available.'), ) help = 'Output the contents of the database as a fixture of the given format.' - args = '[appname ...]' + args = '[appname appname.ModelName ...]' def handle(self, *app_labels, **options): from django.db.models import get_app, get_apps, get_models, get_model format = options.get('format','json') indent = options.get('indent',None) + using = options.get('database', DEFAULT_DB_ALIAS) + connection = connections[using] exclude = options.get('exclude',[]) show_traceback = options.get('traceback', False) + use_natural_keys = options.get('use_natural_keys', False) - excluded_apps = [get_app(app_label) for app_label in exclude] + excluded_apps = set(get_app(app_label) for app_label in exclude) if len(app_labels) == 0: - app_list = SortedDict([(app, None) for app in get_apps() if app not in excluded_apps]) + app_list = SortedDict((app, None) for app in get_apps() if app not in excluded_apps) else: app_list = SortedDict() for label in app_labels: @@ -67,18 +76,91 @@ except KeyError: raise CommandError("Unknown serialization format: %s" % format) + # Now collate the objects to be serialized. objects = [] - for app, model_list in app_list.items(): - if model_list is None: - model_list = get_models(app) - - for model in model_list: - if not model._meta.proxy: - objects.extend(model._default_manager.all()) + for model in sort_dependencies(app_list.items()): + if not model._meta.proxy and router.allow_syncdb(using, model): + objects.extend(model._default_manager.using(using).all()) try: - return serializers.serialize(format, objects, indent=indent) + return serializers.serialize(format, objects, indent=indent, + use_natural_keys=use_natural_keys) except Exception, e: if show_traceback: raise raise CommandError("Unable to serialize database: %s" % e) + +def sort_dependencies(app_list): + """Sort a list of app,modellist pairs into a single list of models. + + The single list of models is sorted so that any model with a natural key + is serialized before a normal model, and any model with a natural key + dependency has it's dependencies serialized first. + """ + from django.db.models import get_model, get_models + # Process the list of models, and get the list of dependencies + model_dependencies = [] + models = set() + for app, model_list in app_list: + if model_list is None: + model_list = get_models(app) + + for model in model_list: + models.add(model) + # Add any explicitly defined dependencies + if hasattr(model, 'natural_key'): + deps = getattr(model.natural_key, 'dependencies', []) + if deps: + deps = [get_model(*d.split('.')) for d in deps] + else: + deps = [] + + # Now add a dependency for any FK or M2M relation with + # a model that defines a natural key + for field in model._meta.fields: + if hasattr(field.rel, 'to'): + rel_model = field.rel.to + if hasattr(rel_model, 'natural_key'): + deps.append(rel_model) + for field in model._meta.many_to_many: + rel_model = field.rel.to + if hasattr(rel_model, 'natural_key'): + deps.append(rel_model) + model_dependencies.append((model, deps)) + + model_dependencies.reverse() + # Now sort the models to ensure that dependencies are met. This + # is done by repeatedly iterating over the input list of models. + # If all the dependencies of a given model are in the final list, + # that model is promoted to the end of the final list. This process + # continues until the input list is empty, or we do a full iteration + # over the input models without promoting a model to the final list. + # If we do a full iteration without a promotion, that means there are + # circular dependencies in the list. + model_list = [] + while model_dependencies: + skipped = [] + changed = False + while model_dependencies: + model, deps = model_dependencies.pop() + + # If all of the models in the dependency list are either already + # on the final model list, or not on the original serialization list, + # then we've found another model with all it's dependencies satisfied. + found = True + for candidate in ((d not in models or d in model_list) for d in deps): + if not candidate: + found = False + if found: + model_list.append(model) + changed = True + else: + skipped.append((model, deps)) + if not changed: + raise CommandError("Can't resolve dependencies for %s in serialized app list." % + ', '.join('%s.%s' % (model._meta.app_label, model._meta.object_name) + for model, deps in sorted(skipped, key=lambda obj: obj[0].__name__)) + ) + model_dependencies = skipped + + return model_list \ No newline at end of file