Nmstatectl: Add --version and version subcommand

Signed-off-by: IsmayilMirzali <ismayilmirzeli@gmail.com>

nmstatectl/nmstatectl.py

@@ -51,12 +51,19 @@ def main():
     setup_subcommand_rollback(subparsers)
     setup_subcommand_set(subparsers)
     setup_subcommand_show(subparsers)
+    setup_subcommand_version(subparsers)
+    parser.add_argument(
+        "--version", action="store_true", help="Display nmstate version"
+    )
 
     if len(sys.argv) == 1:
         parser.print_usage()
         return errno.EINVAL
     args = parser.parse_args()
-    return args.func(args)
+    if args.version:
+        print(libnmstate.__version__)
+    else:
+        return args.func(args)
 
 
 def setup_subcommand_commit(subparsers):
@@ -157,6 +164,17 @@ def setup_subcommand_show(subparsers):
     )
 
 
+def setup_subcommand_version(subparsers):
+    parser_version = subparsers.add_parser(
+        "version", help="Display nmstate version"
+    )
+    parser_version.set_defaults(func=version)
+
+
+def version(args):
+    print(libnmstate.__version__)
+
+
 def commit(args):
     try:
         libnmstate.commit(checkpoint=args.checkpoint)

tests/integration/nmstatectl_test.py

@@ -22,6 +22,7 @@ import os
 import time
 
 
+from libnmstate import __version__
 from libnmstate.schema import Constants
 
 from .testlib import assertlib
@@ -206,6 +207,20 @@ def test_automatic_rollback(eth1_up):
         assertlib.assert_state(clean_state)
 
 
+def test_version_argument():
+    ret = cmdlib.exec_cmd(("nmstatectl", "--version"))
+    rc, out, _ = ret
+    assert rc == cmdlib.RC_SUCCESS, cmdlib.format_exec_cmd_result(ret)
+    assert out.rstrip() == __version__
+
+
+def test_version_command():
+    ret = cmdlib.exec_cmd(("nmstatectl", "version"))
+    rc, out, _ = ret
+    assert rc == cmdlib.RC_SUCCESS, cmdlib.format_exec_cmd_result(ret)
+    assert out.rstrip() == __version__
+
+
 def assert_command(cmd, expected_rc=cmdlib.RC_SUCCESS):
     ret = cmdlib.exec_cmd(cmd)
     returncode = ret[0]