def update_roles(cls, instance, roles):
"""Update existing Release instance with specified roles.
Previous ones are deleted.
IMPORTANT NOTE: attempting to remove roles that are already
assigned to nodes will lead to an Exception.
:param instance: Release instance
:param roles: list of new roles names
:returns: None
"""
db().query(models.Role).filter(
not_(models.Role.name.in_(roles))
).filter(
models.Role.release_id == instance.id
).delete(synchronize_session='fetch')
db().refresh(instance)
added_roles = instance.roles
for role in roles:
if role not in added_roles:
new_role = models.Role(
name=role,
release=instance
)
db().add(new_role)
added_roles.append(role)
db().flush()
def handler_sample():
try:
db().add(models.Role())
db().flush()
except exc.IntegrityError:
db().rollback()
raise
def handler_sample():
db().add(models.Role())
raise web.HTTPError(400)
def handler_sample():
db().add(models.Role())
db().flush()
raise errors.DumpError()
def handler_sample():
try:
db().add(models.Role())
db().flush()
except exc.IntegrityError:
db().commit()