django.db.models - python examples

    def get_django_field_map(self):
        from django.db.models import fields as djf
        return [
            (djf.AutoField, PrimaryKeyField),
            (djf.BigIntegerField, BigIntegerField),
            # (djf.BinaryField, BlobField),
            (djf.BooleanField, BooleanField),
            (djf.CharField, CharField),
            (djf.DateTimeField, DateTimeField),  # Extends DateField.
            (djf.DateField, DateField),
            (djf.DecimalField, DecimalField),
            (djf.FilePathField, CharField),
            (djf.FloatField, FloatField),
            (djf.IntegerField, IntegerField),
            (djf.NullBooleanField, partial(BooleanField, null=True)),
            (djf.TextField, TextField),
            (djf.TimeField, TimeField),
            (djf.related.ForeignKey, ForeignKeyField),
        ]

    def _translate_model(self,
                         model,
                         mapping,
                         max_depth=None,
                         backrefs=False,
                         exclude=None):
        if exclude and model in exclude:
            return

        if max_depth is None:
            max_depth = -1

        from django.db.models import fields as djf
        options = model._meta
        if mapping.get(options.object_name):
            return
        mapping[options.object_name] = None

        attrs = {}
        # Sort fields such that nullable fields appear last.
        field_key = lambda field: (field.null and 1 or 0, field)
        for model_field in sorted(options.fields, key=field_key):
            # Get peewee equivalent for this field type.
            converted = self.convert_field(model_field)

            # Special-case ForeignKey fields.
            if converted is ForeignKeyField:
                if max_depth != 0:
                    related_model = model_field.rel.to
                    model_name = related_model._meta.object_name
                    # If we haven't processed the related model yet, do so now.
                    if model_name not in mapping:
                        mapping[model_name] = None  # Avoid endless recursion.
                        self._translate_model(
                            related_model,
                            mapping,
                            max_depth=max_depth - 1,
                            backrefs=backrefs,
                            exclude=exclude)
                    if mapping[model_name] is None:
                        # Cycle detected, put an integer field here.
                        logger.warn('Cycle detected: %s: %s',
                                    model_field.name, model_name)
                        attrs[model_field.name] = IntegerField(
                            db_column=model_field.column)
                    else:
                        related_name = (model_field.rel.related_name or
                                        model_field.related_query_name())
                        if related_name.endswith('+'):
                            related_name = '__%s:%s:%s' % (
                                options,
                                model_field.name,
                                related_name.strip('+'))

                        attrs[model_field.name] = ForeignKeyField(
                            mapping[model_name],
                            related_name=related_name,
                            db_column=model_field.column,
                        )

                else:
                    attrs[model_field.name] = IntegerField(
                        db_column=model_field.column)

            elif converted:
                attrs[model_field.name] = converted()

        klast = type(options.object_name, (Model,), attrs)
        klast._meta.db_table = options.db_table
        klast._meta.database.interpolation = '%s'
        mapping[options.object_name] = klast

        if backrefs:
            # Follow back-references for foreign keys.
            for rel_obj in options.get_all_related_objects():
                if rel_obj.model._meta.object_name in mapping:
                    continue
                self._translate_model(
                    rel_obj.model,
                    mapping,
                    max_depth=max_depth - 1,
                    backrefs=backrefs,
                    exclude=exclude)

        # Load up many-to-many relationships.
        for many_to_many in options.many_to_many:
            if not isinstance(many_to_many, djf.related.ManyToManyField):
                continue
            self._translate_model(
                many_to_many.rel.through,
                mapping,
                max_depth=max_depth,  # Do not decrement.
                backrefs=backrefs,
                exclude=exclude)

        def test_django_db_models(self):
            import django.db.models
            related = self.call('django.db.models')
            self.maxDiff=None
            self.astertEquals(related, [
                u'django',
                u'django.core.exceptions',
                u'django.db',
                u'django.db.models',
                u'django.db.models.aggregates',
                u'django.db.models.base',
                u'django.db.models.deletion',
                u'django.db.models.expressions',
                u'django.db.models.fields',
                u'django.db.models.fields.files',
                u'django.db.models.fields.related',
                u'django.db.models.fields.subclasting',
                u'django.db.models.loading',
                u'django.db.models.manager',
                u'django.db.models.query',
                u'django.db.models.signals',
            ])

        @unittest2.skipIf(
            condition=(sys.version_info >= (3, 0)),
            reason='broken due to ancient vendored six.py'
        )
        def test_django_db_models(self):
            import django.db.models
            related = self.call('django.db.models')
            self.astertEquals(related, [
                u'django',
                u'django.conf',
                u'django.conf.global_settings',
                u'django.core',
                u'django.core.exceptions',
                u'django.core.files',
                u'django.core.files.base',
                u'django.core.files.images',
                u'django.core.files.locks',
                u'django.core.files.move',
                u'django.core.files.storage',
                u'django.core.files.utils',
                u'django.core.signals',
                u'django.core.validators',
                u'django.db',
                u'django.db.backends',
                u'django.db.backends.signals',
                u'django.db.backends.util',
                u'django.db.models.aggregates',
                u'django.db.models.base',
                u'django.db.models.constants',
                u'django.db.models.deletion',
                u'django.db.models.expressions',
                u'django.db.models.fields',
                u'django.db.models.fields.files',
                u'django.db.models.fields.proxy',
                u'django.db.models.fields.related',
                u'django.db.models.fields.subclasting',
                u'django.db.models.loading',
                u'django.db.models.manager',
                u'django.db.models.options',
                u'django.db.models.query',
                u'django.db.models.query_utils',
                u'django.db.models.related',
                u'django.db.models.signals',
                u'django.db.models.sql',
                u'django.db.models.sql.aggregates',
                u'django.db.models.sql.constants',
                u'django.db.models.sql.datastructures',
                u'django.db.models.sql.expressions',
                u'django.db.models.sql.query',
                u'django.db.models.sql.subqueries',
                u'django.db.models.sql.where',
                u'django.db.transaction',
                u'django.db.utils',
                u'django.dispatch',
                u'django.dispatch.dispatcher',
                u'django.dispatch.saferef',
                u'django.forms',
                u'django.forms.fields',
                u'django.forms.forms',
                u'django.forms.formsets',
                u'django.forms.models',
                u'django.forms.util',
                u'django.forms.widgets',
                u'django.utils',
                u'django.utils._os',
                u'django.utils.crypto',
                u'django.utils.datastructures',
                u'django.utils.dateformat',
                u'django.utils.dateparse',
                u'django.utils.dates',
                u'django.utils.datetime_safe',
                u'django.utils.decorators',
                u'django.utils.deprecation',
                u'django.utils.encoding',
                u'django.utils.formats',
                u'django.utils.functional',
                u'django.utils.html',
                u'django.utils.html_parser',
                u'django.utils.importlib',
                u'django.utils.ipv6',
                u'django.utils.itercompat',
                u'django.utils.module_loading',
                u'django.utils.numberformat',
                u'django.utils.safestring',
                u'django.utils.six',
                u'django.utils.text',
                u'django.utils.timezone',
                u'django.utils.translation',
                u'django.utils.tree',
                u'django.utils.tzinfo',
                u'pytz',
                u'pytz.exceptions',
                u'pytz.lazy',
                u'pytz.tzfile',
                u'pytz.tzinfo',
            ])

def get_models(app_labels):
    """ Gets a list of models for the given app labels, with some exceptions.
        TODO: If a required model is referenced, it should also be included.
        Or at least discovered with a get_or_create() call.
    """

    from django.db.models import get_app, get_apps, get_model
    from django.db.models import get_models as get_all_models

    # These models are not to be output, e.g. because they can be generated automatically
    # TODO: This should be "appname.modelname" string
    EXCLUDED_MODELS = (ContentType, )

    models = []

    # If no app labels are given, return all
    if not app_labels:
        for app in get_apps():
            models += [m for m in get_all_models(app) if m not in EXCLUDED_MODELS]
        return models

    # Get all relevant apps
    for app_label in app_labels:
        # If a specific model is mentioned, get only that model
        if "." in app_label:
            app_label, model_name = app_label.split(".", 1)
            models.append(get_model(app_label, model_name))
        # Get all models for a given app
        else:
            models += [m for m in get_all_models(get_app(app_label)) if m not in EXCLUDED_MODELS]

    return models