python-bareos: improve protocolversion handling

python-bareos/bareos/bsock/directorconsole.py

@@ -104,9 +104,11 @@ def argparser_add_default_command_line_arguments(argparser):
 
         group.add_argument(
             "--protocolversion",
-            default=ProtocolVersions.last,
             type=int,
-            help="Specify the Bareos console protocol version. Default: %(default)s (current).",
+            choices=set(protocolversion.value for protocolversion in ProtocolVersions)
+            | set([0]),
+            default=ProtocolVersions.last.value,
+            help="Specify the Bareos console protocol version (0: auto-detect, %(default)s: latest). Default: %(default)s.",
             dest="BAREOS_protocolversion",
         )
 
@@ -192,7 +194,7 @@ def __init__(
         if tls_version is not None:
             self.tls_version = tls_version
         self.identity_prefix = "R_CONSOLE"
-        if protocolversion is not None:
+        if protocolversion is not None and protocolversion > 0:
             self.requested_protocol_version = int(protocolversion)
             self.protocol_messages.set_version(self.requested_protocol_version)
         self.connect(

python-bareos/bareos/bsock/protocolversions.py

@@ -1,6 +1,6 @@
 #   BAREOS - Backup Archiving REcovery Open Sourced
 #
-#   Copyright (C) 2019-2021 Bareos GmbH & Co. KG
+#   Copyright (C) 2019-2024 Bareos GmbH & Co. KG
 #
 #   This program is Free Software; you can redistribute it and/or
 #   modify it under the terms of version three of the GNU Affero General Public
@@ -21,8 +21,10 @@
 Bareos Protocol Versions.
 """
 
+from enum import IntEnum
 
-class ProtocolVersions(object):
+
+class ProtocolVersions(IntEnum):
     """
     Bareos Protocol Versions.
     """