def get_revert_migrations(self, current_migrations, backup_migrations):
current_migrations, all_migrations = itertools.tee(
reversed(
list(
map(
Migration,
filter(None, current_migrations.splitlines()),
))))
all_migrations = utils.OrderedSet(all_migrations)
backup_migrations = reversed(
list(map(
Migration,
filter(None, backup_migrations.splitlines()),
)))
revert_migrations = utils.OrderedDict()
while True:
while True:
backup_migration = next(backup_migrations, None)
if not backup_migration or backup_migration in all_migrations:
break
for current_migration in current_migrations:
if current_migration == backup_migration:
break
revert_migration = self._get_parent_migration(
current_migration,
migrations=all_migrations,
)
revert_migrations[current_migration.app] = revert_migration
if backup_migration is None:
return revert_migrations.values()
def get_values_to_add(self, service, attr):
new_values = self.get_new_values(service, attr)
new_values = utils.OrderedSet(new_values)
if not self.force_add:
current_values = self.get_current_values(service.info)
new_values -= current_values
return list(new_values) or None
def get_values_to_remove(self, service, attr):
current_values = self.get_current_values(service.info)
current_values = utils.OrderedSet(current_values)
if not self.force_rm:
new_values = self.get_new_values(service, attr)
new_values = map(self.cast_rm, new_values)
new_values = (value for values in new_values for value in (
values if isinstance(values, (list, tuple)) else [values]))
current_values -= new_values
return list(current_values) or None