Add utils for local_orchestration_client

Add a utils/heat.py which can be used by both tripleoclient and
tripleo-ansible to launch and configure a heatclient for ephemeral Heat.

Depends-On: I9d9dea09a36914cffaef1d251c49f3c4fea4fa68
Change-Id: I2c3e9088bf92146b07d46288c2264368e15aa63b
Signed-off-by: James Slagle <jslagle@redhat.com>

tripleo_common/utils/heat.py

@@ -0,0 +1,97 @@
+# Copyright (c) 2021 Red Hat, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+import os
+from osc_lib import utils as osc_lib_utils
+
+
+LOG = logging.getLogger(__name__)
+heatclient = None
+
+
+class EphemeralHeatClient(object):
+    """A Heat client shim class to be used with ephemeral Heat.
+
+    When the heat client is used to talk to the Heat API, the environment will
+    be set with the correct variable configuration to configure Keystone for
+    auth type none and to use a direct endpoint.
+
+    After the client is finished, the environment is restored. This is
+    necessary so that the entire system environment is not reconfigured for
+    auth_type=none for the duration of the tripleoclient execution.
+
+    :param heat: Heat client
+    :type heat: `heatclient.heatclient`
+
+    """
+
+    def __init__(self, heat, host, port):
+        self.heat = heat
+        self.host = host
+        self.port = port
+        os.environ['OS_HEAT_TYPE'] = 'ephemeral'
+        os.environ['OS_HEAT_HOST'] = host
+        os.environ['OS_HEAT_PORT'] = str(port)
+
+    def save_environment(self):
+        self.environ = os.environ.copy()
+        for v in ('OS_USER_DOMAIN_NAME',
+                  'OS_PROJECT_DOMAIN_NAME',
+                  'OS_PROJECT_NAME'):
+            os.environ.pop(v, None)
+
+        os.environ['OS_AUTH_TYPE'] = "none"
+        os.environ['OS_ENDPOINT'] = self.heat.http_client.endpoint
+
+    def restore_environment(self):
+        os.environ = self.environ.copy()
+
+    def __getattr__(self, attr):
+        self.save_environment()
+        try:
+            val = getattr(self.heat, attr)
+        finally:
+            self.restore_environment()
+        return val
+
+
+def local_orchestration_client(host="127.0.0.1", api_port=8006):
+    """Returns a local orchestration service client"""
+
+    API_VERSIONS = {
+        '1': 'heatclient.v1.client.Client',
+    }
+
+    heat_client = osc_lib_utils.get_client_class(
+        'tripleoclient',
+        '1',
+        API_VERSIONS)
+    LOG.debug('Instantiating local_orchestration client for '
+              'host %s, port %s: %s',
+              host, api_port, heat_client)
+
+    endpoint = 'http://%s:%s/v1/admin' % (host, api_port)
+    client = heat_client(
+        endpoint=endpoint,
+        username='admin',
+        password='fake',
+        region_name='regionOne',
+        token='fake',
+    )
+
+    global heatclient
+    heatclient = EphemeralHeatClient(client, host, api_port)
+    return heatclient