undercloud: introduce deployment_user parameter

deployment_user is a new parameter, default to getpass.getuser(),
will feed DeploymentUser parameter in THT, primarly used to add the
user to the 'docker' group, so our operators can run the `overcloud
container` commands when the undercloud is containerized.

Right now, the docker group was modified in puppet with
instack-undercloud but with the heat-installer we want to do it in
tripleoclient. DeploymentUser was chosen to be "standard" and can be
used for both undercloud & overclouds notions.

Change-Id: Ia5cc7b34ebee8cf2f49300ce23050370d5f1038a

releasenotes/notes/deployment_user-bc451a45754035b9.yaml

@@ -0,0 +1,7 @@
+---
+features:
+  - |
+    Introduce deployment_user parameter, default to the current user,
+    will feed DeploymentUser parameter in THT, primarly used to add the
+    user to the 'docker' group, so our operators can run the `overcloud
+    container` commands when the undercloud is containerized.

tripleoclient/tests/test_utils.py

@@ -204,6 +204,12 @@ class TestEnsureRunAsNormalUser(TestCase):
         self.assertRaises(exceptions.RootUserExecution,
                           utils.ensure_run_as_normal_user)
 
+    @mock.patch('getpass.getuser')
+    def test_get_deployment_user(self, mock_getpass):
+        mock_getpass.return_value = 'stack'
+        u = utils.get_deployment_user()
+        self.assertEqual('stack', u)
+
 
 class TestCreateOvercloudRC(TestCase):
 

tripleoclient/utils.py

@@ -16,6 +16,7 @@
 from __future__ import print_function
 import csv
 import datetime
+import getpass
 import glob
 import hashlib
 import logging
@@ -428,6 +429,11 @@ def ensure_run_as_normal_user():
             ' Switch to a normal user.')
 
 
+def get_deployment_user():
+    """Return the user name which is used to deploy the cloud"""
+    return getpass.getuser()
+
+
 def capabilities_to_dict(caps):
     """Convert the Node's capabilities into a dictionary."""
     if not caps:

tripleoclient/v1/undercloud_config.py

@@ -23,6 +23,7 @@ import logging
 import netaddr
 import os
 from oslo_config import cfg
+from tripleoclient import utils
 from tripleoclient.v1 import undercloud_preflight
 import yaml
 
@@ -65,6 +66,11 @@ PATHS = Paths()
 # When adding new options to the lists below, make sure to regenerate the
 # sample config by running "tox -e genconfig" in the project root.
 _opts = [
+    cfg.StrOpt('deployment_user',
+               help=('User used to run openstack undercloud install command '
+                     'which will be used to add the user to the docker group, '
+                     'required to upload containers'),
+               ),
     cfg.StrOpt('undercloud_hostname',
                help=('Fully qualified hostname (including domain) to set on '
                      'the Undercloud. If left unset, the '
@@ -602,6 +608,9 @@ def prepare_undercloud_deploy(upgrade=False, no_validations=False):
                 tht_templates,
                 'environments/services-docker/undercloud-keepalived.yaml')]
 
+    u = CONF.get('deployment_user') or utils.get_deployment_user()
+    env_data['DeploymentUser'] = u
+
     deploy_args += [
         "-e", os.path.join(tht_templates, "environments/docker.yaml"),
         "-e",