TCIB: add --rhel-modules argument

--rhel-modules is a new argument that will let us override the hardcoded
RHEL module versions that are provided in the base image.

For example, if we want to build the images against a specific module
version, we'll now be able to do the following:

  $ openstack tripleo container image build --rhel-modules \
        redis:5,virt:8.3

Note: for now we're opinionated about the RHEL modules that we support
and the --rhel-modules won't allow to install any modules, but only the
ones that we support: ['container-tools', 'mariadb', 'redis', 'virt'].
The reason is that in theory all necessary modules should be provided in
the base image layout in tripleo-common, and the use case here is being
able to change their version from the CLI, specially for our release
challenges with future OSP zstreams.


Change-Id: Icaeabb2e7cb7adbbd7d2ef563dd613f2aacf8fe3
(cherry picked from commit a3b3aeb93b)

tripleoclient/v2/tripleo_container_image.py

@@ -45,6 +45,7 @@ DEFAULT_AUTHFILE = "{}/containers/auth.json".format(
 DEFAULT_ENV_AUTHFILE = os.environ.get("REGISTRY_AUTH_FILE", DEFAULT_AUTHFILE)
 DEFAULT_CONFIG = "tripleo_containers.yaml"
 DEFAULT_TCIB_CONFIG_BASE = "tcib"
+SUPPORTED_RHEL_MODULES = ['container-tools', 'mariadb', 'redis', 'virt']
 
 
 class Build(command.Command):
@@ -207,6 +208,14 @@ class Build(command.Command):
                 "(default: %(default)s)"
             ),
         )
+        parser.add_argument(
+            "--rhel-modules",
+            dest="rhel_modules",
+            metavar="<rhel-modules>",
+            default=None,
+            help=_("A comma separated list of RHEL modules to enable with "
+                   "their version. Example: 'mariadb:10.3,virt:8.3'."),
+        )
         return parser
 
     def imagename_to_regex(self, imagename):
@@ -460,6 +469,22 @@ class Build(command.Command):
                 }
             )
 
+            if parsed_args.rhel_modules:
+                rhel_modules = {}
+                for module in parsed_args.rhel_modules.split(','):
+                    try:
+                        name, version = module.split(':', 1)
+                    except Exception:
+                        raise ValueError('Wrong format for --rhel-modules, '
+                                         'must be a comma separated list of '
+                                         '<module>:<version>')
+                    if name not in SUPPORTED_RHEL_MODULES:
+                        raise ValueError('{} is not part of supported modules'
+                                         ' {}'.format(name,
+                                                      SUPPORTED_RHEL_MODULES))
+                    rhel_modules.update({name: version})
+                image_config['tcib_rhel_modules'] = rhel_modules
+
             # NOTE(cloudnull): Check if the reference config has a valid
             #                  "from" option. If the reference "from"
             #                  option is valid, it will be used.