""" Startmigration command, version 2. """ from __future__ import print_function import sys import os import re import string import random import inspect from optparse import make_option try: set except NameError: from sets import Set as set from django.core.management.base import BaseCommand from django.core.management.color import no_style from django.core.exceptions import ImproperlyConfigured from django.db import models from django.conf import settings from south.migration import Migrations, migrate_app from south.models import MigrationHistory from south.exceptions import NoMigrations from south.creator import changes, actions, freezer from south.management.commands.datamigration import Command as DataCommand class Command(DataCommand): option_list = DataCommand.option_list + ( make_option('--add-model', action='append', dest='added_model_list', type='string', help='Generate a Create Table migration for the specified model. Add multiple models to this migration with subsequent --add-model parameters.'), make_option('--add-field', action='append', dest='added_field_list', type='string', help='Generate an Add Column migration for the specified modelname.fieldname - you can use this multiple times to add more than one column.'), make_option('--add-index', action='append', dest='added_index_list', type='string', help='Generate an Add Index migration for the specified modelname.fieldname - you can use this multiple times to add more than one column.'), make_option('--initial', action='store_true', dest='initial', default=False, help='Generate the initial schema for the app.'), make_option('--auto', action='store_true', dest='auto', default=False, help='Attempt to automatically detect differences from the last migration.'), make_option('--empty', action='store_true', dest='empty', default=False, help='Make a blank migration.'), make_option('--update', action='store_true', dest='update', default=False, help='Update the most recent migration instead of creating a new one. Rollback this migration if it is already applied.'), ) help = "Creates a new template schema migration for the given app" usage_str = "Usage: ./manage.py schemamigration appname migrationname [--empty] [--initial] [--auto] [--add-model ModelName] [--add-field ModelName.field_name] [--stdout]" def handle(self, app=None, name="", added_model_list=None, added_field_list=None, freeze_list=None, initial=False, auto=False, stdout=False, added_index_list=None, verbosity=1, empty=False, update=False, **options): # Any supposed lists that are None become empty lists added_model_list = added_model_list or [] added_field_list = added_field_list or [] added_index_list = added_index_list or [] freeze_list = freeze_list or [] # --stdout means name = - if stdout: name = "-" # Only allow valid names if re.search('[^_\w]', name) and name != "-": self.error("Migration names should contain only alphanumeric characters and underscores.") # Make sure options are compatable if initial and (added_model_list or added_field_list or auto): self.error("You cannot use --initial and other options together\n" + self.usage_str) if auto and (added_model_list or added_field_list or initial): self.error("You cannot use --auto and other options together\n" + self.usage_str) if not app: self.error("You must provide an app to create a migration for.\n" + self.usage_str) # See if the app exists app = app.split(".")[-1] try: app_module = models.get_app(app) except ImproperlyConfigured: print("There is no enabled application matching '%s'." % app) return # Get the Migrations for this app (creating the migrations dir if needed) migrations = Migrations(app, force_creation=True, verbose_creation=int(verbosity) > 0) # What actions do we need to do? if auto: # Get the old migration try: last_migration = migrations[-2 if update else -1] except IndexError: self.error("You cannot use --auto on an app with no migrations. Try --initial.") # Make sure it has stored models if migrations.app_label() not in getattr(last_migration.migration_class(), "complete_apps", []): self.error("You cannot use automatic detection, since the previous migration does not have this whole app frozen.\nEither make migrations using '--freeze %s' or set 'SOUTH_AUTO_FREEZE_APP = True' in your settings.py." % migrations.app_label()) # Alright, construct two model dicts to run the differ on. old_defs = dict( (k, v) for k, v in last_migration.migration_class().models.items() if k.split(".")[0] == migrations.app_label() ) new_defs = dict( (k, v) for k, v in freezer.freeze_apps([migrations.app_label()]).items() if k.split(".")[0] == migrations.app_label() ) change_source = changes.AutoChanges( migrations = migrations, old_defs = old_defs, old_orm = last_migration.orm(), new_defs = new_defs, ) elif initial: # Do an initial migration change_source = changes.InitialChanges(migrations) else: # Read the commands manually off of the arguments if (added_model_list or added_field_list or added_index_list): change_source = changes.ManualChanges( migrations, added_model_list, added_field_list, added_index_list, ) elif empty: change_source = None else: print("You have not passed any of --initial, --auto, --empty, --add-model, --add-field or --add-index.", file=sys.stderr) sys.exit(1) # Validate this so we can access the last migration without worrying if update and not migrations: self.error("You cannot use --update on an app with no migrations.") # if not name, there's an error if not name: if change_source: name = change_source.suggest_name() if update: name = re.sub(r'^\d{4}_', '', migrations[-1].name()) if not name: self.error("You must provide a name for this migration\n" + self.usage_str) # Get the actions, and then insert them into the actions lists forwards_actions = [] backwards_actions = [] if change_source: for action_name, params in change_source.get_changes(): # Run the correct Action class try: action_class = getattr(actions, action_name) except AttributeError: raise ValueError("Invalid action name from source: %s" % action_name) else: action = action_class(**params) action.add_forwards(forwards_actions) action.add_backwards(backwards_actions) print(action.console_line(), file=sys.stderr) # Nowt happen? That's not good for --auto. if auto and not forwards_actions: self.error("Nothing seems to have changed.") # Work out which apps to freeze apps_to_freeze = self.calc_frozen_apps(migrations, freeze_list) # So, what's in this file, then? file_contents = self.get_migration_template() % { "forwards": "\n".join(forwards_actions or [" pass"]), "backwards": "\n".join(backwards_actions or [" pass"]), "frozen_models": freezer.freeze_apps_to_string(apps_to_freeze), "complete_apps": apps_to_freeze and "complete_apps = [%s]" % (", ".join(map(repr, apps_to_freeze))) or "" } # Deal with update mode as late as possible, avoid a rollback as long # as something else can go wrong. if update: last_migration = migrations[-1] if MigrationHistory.objects.filter(applied__isnull=False, app_name=app, migration=last_migration.name()): print("Migration to be updated, %s, is already applied, rolling it back now..." % last_migration.name(), file=sys.stderr) migrate_app(migrations, 'current-1', verbosity=verbosity) for ext in ('py', 'pyc'): old_filename = "%s.%s" % (os.path.join(migrations.migrations_dir(), last_migration.filename), ext) if os.path.isfile(old_filename): os.unlink(old_filename) migrations.remove(last_migration) # See what filename is next in line. We assume they use numbers. new_filename = migrations.next_filename(name) # - is a special name which means 'print to stdout' if name == "-": print(file_contents) # Write the migration file if the name isn't - else: fp = open(os.path.join(migrations.migrations_dir(), new_filename), "w") fp.write(file_contents) fp.close() verb = 'Updated' if update else 'Created' if empty: print("%s %s. You must now edit this migration and add the code for each direction." % (verb, new_filename), file=sys.stderr) else: print("%s %s. You can now apply this migration with: ./manage.py migrate %s" % (verb, new_filename, app), file=sys.stderr) def get_migration_template(self): return MIGRATION_TEMPLATE MIGRATION_TEMPLATE = """# -*- coding: utf-8 -*- from south.utils import datetime_utils as datetime from south.db import db from south.v2 import SchemaMigration from django.db import models class Migration(SchemaMigration): def forwards(self, orm): %(forwards)s def backwards(self, orm): %(backwards)s models = %(frozen_models)s %(complete_apps)s"""