Merge lp:~ack/apt-btrfs-snapshot/fix-arg-parser into lp:apt-btrfs-snapshot

[Alberto Donato]

This fixes the argparse setup not to error if no command is provided:

$ sudo apt-btrfs-snapshot
Traceback (most recent call last):
  File "/usr/bin/apt-btrfs-snapshot", line 98, in <module>
    if args.command == "supported":
AttributeError: 'Namespace' object has no attribute 'command'

by setting the command parameter as required.

[Michael Vogt (mvo)]

Looks great, thanks for working on this!

review: Approve

[Alberto Donato (ack)]

@mvo can this be merged?

Unmerged revisions

55. By Alberto Donato on 2017-08-09

Fix ArgumentParser setup.

=== modified file 'apt-btrfs-snapshot'
--- apt-btrfs-snapshot	2015-10-16 09:27:08 +0000
+++ apt-btrfs-snapshot	2017-08-09 14:50:33 +0000
@@ -42,39 +42,33 @@
     parser = argparse.ArgumentParser(description=description)
     parser.add_argument("--debug", action="store_true", default=False,
                         help="enable debug output")
-    subparser = parser.add_subparsers(title="Commands")
+    subparser = parser.add_subparsers(dest="command", metavar="command")
+    subparser.required = True
     # supported
     command = subparser.add_parser(
         "supported", help=_("Print if snapshots are supported"))
-    command.set_defaults(command="supported")
     # list
     command = subparser.add_parser(
         "list", help=_("List available snapshots"))
-    command.set_defaults(command="list")
     # snapshot
     command = subparser.add_parser(
         "snapshot", help=_("Create a new snapshot"))
-    command.set_defaults(command="snapshot")
     # set-default
     command = subparser.add_parser(
         "set-default", help=_("Revert to previous snapshot"))
     command.add_argument("snapshot")
-    command.set_defaults(command="set-default")
     # delete
     command = subparser.add_parser(
         "delete", help=_("Delete snapshot"))
     command.add_argument("snapshot")
-    command.set_defaults(command="delete")
     # list-older-than
     command = subparser.add_parser(
         "list-older-than", help=_("Show snapshots older than N days"))
     command.add_argument("time")
-    command.set_defaults(command="list-older-than")
     # delete-older-than
     command = subparser.add_parser(
         "delete-older-than", help=_("Delete snapshots older than N days"))
     command.add_argument("time")
-    command.set_defaults(command="delete-older-than")
 
     # parse args
     args = parser.parse_args()
@@ -113,8 +107,6 @@
         res = apt_btrfs.print_btrfs_root_snapshots_older_than(args.time)
     elif args.command == "delete-older-than":
         res = apt_btrfs.clean_btrfs_root_snapshots_older_than(args.time)
-    else:
-        print(_("ERROR: Unhandled command: '%s'") % args.command)
 
     # return the right exit code
     if res: