Fix condition for checking whether substitution is secret

This is to fix the condition in secrets_manager used to determine
whether the substitution is secret. It currently checks whether the
potential secret reference contains the substring
of 'key-manager/v1/secrets' but the environment-agnostic way
of doing this is to check whether the secret reference contains
the barbican endpoint registered under CONF.barbican.api_endpoint.

Change-Id: I633021571255c8393e19ec60a614ede981a86d9f

deckhand/conf/config.py

@@ -28,6 +28,7 @@ Barbican options for allowing Deckhand to communicate with Barbican.
 barbican_opts = [
     cfg.StrOpt(
         'api_endpoint',
+        default='http://127.0.0.1/key-manager',
         sample_default='http://barbican.example.org:9311/',
         help='URL override for the Barbican API endpoint.'),
 ]

deckhand/engine/secrets_manager.py

@@ -15,6 +15,7 @@
 import copy
 import re
 
+from oslo_config import cfg
 from oslo_log import log as logging
 import six
 
@@ -23,6 +24,7 @@ from deckhand.engine import document_wrapper
 from deckhand import errors
 from deckhand import utils
 
+CONF = cfg.CONF
 LOG = logging.getLogger(__name__)
 
 CLEARTEXT = 'cleartext'
@@ -177,9 +179,8 @@ class SecretsSubstitution(object):
                     (document.schema, document.name), document)
 
     def _is_barbican_ref(self, src_secret):
-        # TODO(fmontei): Make this more robust.
         return (isinstance(src_secret, six.string_types) and
-                'key-manager/v1/secrets' in src_secret)
+                    src_secret.startswith(CONF.barbican.api_endpoint))
 
     def substitute_all(self, documents):
         """Substitute all documents that have a `metadata.substitutions` field.

deckhand/tests/unit/base.py

@@ -23,6 +23,7 @@ from oslo_log import log as logging
 import testtools
 
 from deckhand.db.sqlalchemy import api as db_api
+from deckhand.tests.unit import fixtures as dh_fixtures
 
 CONF = cfg.CONF
 logging.register_options(CONF)
@@ -34,6 +35,8 @@ class DeckhandTestCase(testtools.TestCase):
     def setUp(self):
         super(DeckhandTestCase, self).setUp()
         self.useFixture(fixtures.FakeLogger('deckhand'))
+        self.useFixture(dh_fixtures.ConfPatcher(
+            api_endpoint='http://127.0.0.1/key-manager', group='barbican'))
 
     def override_config(self, name, override, group=None):
         CONF.set_override(name, override, group)