InvalidBackendURL for multi backend

[Tommy Nguyen]

This is a repost of https://lists.nongnu.org/archive/html/duplicity-talk/2019-11/msg00000.html since I did not get a response.

duplicity 0.8.05
Python 3.7.5
Fedora 31
Linux
$ duplicity collection-status
'multi:///home/tom/duplicity.json?mode=mirror'
InvalidBackendURL: Syntax error (path) in:
b'file:///home/tom/second_drive/backup/'

My duplicity.json contains the following contents:

[
    {
        "description": "second drive",
        "url": "file:///home/tom/second_drive/backup/"
    },
    {
        "description": "third drive",
        "url": "file:///home/tom/third_drive/backup/"
    }
]

Using 'file:///home/tom/second_drive/backup/' directly seems to work
fine, so the problem seems to be related to the multi backend. Here is
a full stack trace:

MultiBackend: use store b'file:///home/tom/second_drive/backup/'
Using temporary directory /tmp/duplicity-q8pkrkbc-tempdir
User error detail: Traceback (innermost last):
  File "/usr/bin/duplicity", line 101, in <module>
    with_tempdir(main)
  File "/usr/bin/duplicity", line 87, in with_tempdir
    fn()
  File "/usr/lib64/python3.7/site-packages/duplicity/dup_main.py", line
1519, in main
    action = commandline.ProcessCommandLine(sys.argv[1:])
  File "/usr/lib64/python3.7/site-packages/duplicity/commandline.py",
line 1203, in ProcessCommandLine
    globals.backend = backend.get_backend(args[0])
  File "/usr/lib64/python3.7/site-packages/duplicity/backend.py", line
225, in get_backend
    obj = get_backend_object(url_string)
  File "/usr/lib64/python3.7/site-packages/duplicity/backend.py", line
211, in get_backend_object
    return factory(pu)
  File "/usr/lib64/python3.7/site-
packages/duplicity/backends/multibackend.py", line 197, in __init__
    store = duplicity.backend.get_backend(url)
  File "/usr/lib64/python3.7/site-packages/duplicity/backend.py", line
225, in get_backend
    obj = get_backend_object(url_string)
  File "/usr/lib64/python3.7/site-packages/duplicity/backend.py", line
188, in get_backend_object
    if not is_backend_url(url_string):
  File "/usr/lib64/python3.7/site-packages/duplicity/backend.py", line
172, in is_backend_url
    pu = ParsedUrl(url_string)
  File "/usr/lib64/python3.7/site-packages/duplicity/backend.py", line
274, in __init__
    raise InvalidBackendURL(u"Syntax error (path) in: %s" % url_string)
 duplicity.errors.InvalidBackendURL: Syntax error (path) in:
b'file:///home/tom/second_drive/backup/'

Based on my debugging, the issue is that the type of pu.path is a bytes string when urllib.parse.unquote expects a str.

[Vojtech Horky (vojtech-horky)]

Confirming and adding one more observation. backend.py gets data from two sources: command line and the multibackend JSON so one of them comes as normal string, the other one as bytes. So any fix needs to unify this across the whole class.

[Tim Passingham (tim-8aw3u04umo)]

I am on ubuntu 19.10, running duplicity 8.04-2-ubuntu1
I get a similar error, but I don't know if it's the same. I tried looking at ppas for a later version but didn't find one.

Traceback (innermost last):
  File "/usr/bin/duplicity", line 107, in <module>
    with_tempdir(main)
  File "/usr/bin/duplicity", line 93, in with_tempdir
    fn()
  File "/usr/lib/python3/dist-packages/duplicity/dup_main.py", line 1522, in main
    action = commandline.ProcessCommandLine(sys.argv[1:])
  File "/usr/lib/python3/dist-packages/duplicity/commandline.py", line 1200, in ProcessCommandLine
    globals.backend = backend.get_backend(args[0])
  File "/usr/lib/python3/dist-packages/duplicity/backend.py", line 225, in get_backend
    obj = get_backend_object(url_string)
  File "/usr/lib/python3/dist-packages/duplicity/backend.py", line 211, in get_backend_object
    return factory(pu)
  File "/usr/lib/python3/dist-packages/duplicity/backends/giobackend.py", line 81, in __init__
    ensure_dbus()
  File "/usr/lib/python3/dist-packages/duplicity/backends/giobackend.py", line 37, in ensure_dbus
    lines = output.split(u'\n')
 TypeError: a bytes-like object is required, not 'str'

[Kenneth Loafman (kenneth-loafman)]

This is located in https://code.launchpad.net/~duplicity-team/+archive/ubuntu/daily-dev-trunk