from barbicanclient import client
import base64
from keystoneauth1.identity import v2
from keystoneauth1 import session
import os

_AES_256_SIZE=32 # bytes
AES_256_KEY = os.urandom(_AES_256_SIZE)

auth = v2.Password(username=os.environ['OS_USERNAME'],
                   password=os.environ['OS_PASSWORD'],
                   auth_url=os.environ['OS_AUTH_URL'])
sess = session.Session(auth=auth)
barbican = client.Client(session=sess)
key = barbican.secrets.create(secret_type='symmetric',
                              payload=base64.b64encode(AES_256_KEY).decode('UTF-8'),
                              payload_content_type='application/octet-stream',
                              payload_content_encoding='base64')
key.store()
# At this point you should persist KEY_REF somewhere so you can retrieve the key later.
KEY_REF = key.secret_ref

# Later, when you wan to retrieve the key for usage do this
retrieved_key = barbican.secrets.get(KEY_REF)
key_bytes = retrieved_key.payload

# You should get the same original key that was stored
assert AES_256_KEY == key_bytes