runserver.py 文件源码

def check_migrations(self):
        """
        Checks to see if the set of migrations on disk matches the
        migrations in the database. Prints a warning if they don't match.
        """
        try:
            executor = MigrationExecutor(connections[DEFAULT_DB_ALIAS])
        except ImproperlyConfigured:
            # No databases are configured (or the dummy one)
            return
        except MigrationSchemaMissing:
            self.stdout.write(self.style.NOTICE(
                "\nNot checking migrations as it is not possible to access/create the django_migrations table."
            ))
            return

        plan = executor.migration_plan(executor.loader.graph.leaf_nodes())
        if plan:
            self.stdout.write(self.style.NOTICE(
                "\nYou have unapplied migrations; your app may not work properly until they are applied."
            ))
            self.stdout.write(self.style.NOTICE("Run 'python manage.py migrate' to apply them.\n"))

# Kept for backward compatibility