Duplicity

AttributeError: 'NoneType' object has no attribute 'encode'

Bug #1572598 reported by Tom Schnittke on 2016-04-20

This bug affects 1 person

Affects		Status	Importance	Assigned to	Milestone
	Duplicity	Invalid	Medium	Unassigned

Bug Description

Hello,

following situation:

i'm doing a backup with

duplicity v0.7.07.1 (0.7.07.1-0ubuntu0ppa1211~ubuntu15.10.1)
ubuntu 14.04 @ amd64

and using an remote SFTP(key-based-auth) server.

When i start it in a bash-session, thus, in a reqular terminal, everything works fine.
Backup runs through, without any complains.

But when i try to start it with cron i get following error (@ log level debug):

-------
...
Running 'sftp -oServerAliveInterval=15 -oServerAliveCountMax=2 <email address hidden>'
State = sftp, Before = '<email address hidden>'s'
Backtrace of previous error: Traceback (innermost last):
  File "/usr/lib/python2.7/dist-packages/duplicity/backend.py", line 367, in inner_retry
    return fn(self, *args)
  File "/usr/lib/python2.7/dist-packages/duplicity/backend.py", line 569, in list
    return [tobytes(x) for x in self.backend._list()]
  File "/usr/lib/python2.7/dist-packages/duplicity/backends/ssh_pexpect_backend.py", line 280, in _list
    l = self.run_sftp_command(commandline, commands).split('\n')[1:]
  File "/usr/lib/python2.7/dist-packages/duplicity/backends/ssh_pexpect_backend.py", line 190, in run_sftp_command
    child.sendline(self.password)
  File "/usr/lib/python2.7/dist-packages/pexpect/__init__.py", line 1036, in sendline
    n = self.send(s)
  File "/usr/lib/python2.7/dist-packages/pexpect/__init__.py", line 1024, in send
    s = self._coerce_send_string(s)
  File "/usr/lib/python2.7/dist-packages/pexpect/__init__.py", line 496, in _coerce_send_string
    return s.encode('utf-8')
AttributeError: 'NoneType' object has no attribute 'encode'

-------
This message repeats 5 times with an interval of about 10 seconds or so and then duplicity quits.

@log-level info the main error part shown is:
" AttributeError: 'NoneType' object has no attribute 'encode'"

Please see the full backup.log attached.

Thanks!

Revision history for this message

Tom Schnittke (ilya-ruprecht) wrote on 2016-04-20:

backup.log Edit (8.6 KiB, text/plain)

Revision history for this message

Kenneth Loafman (kenneth-loafman) wrote on 2016-04-20:

This sounds like either an older version of pexpect. Please run "sudo pip install --update pexpect" and try this again.

Changed in duplicity:
assignee:	nobody → Kenneth Loafman (kenneth-loafman)
importance:	Undecided → Medium
milestone:	none → 0.7.08
status:	New → In Progress

Revision history for this message

Tom Schnittke (ilya-ruprecht) wrote on 2016-04-21:

ok, will do.

current python-pexpect version installed is

dpkg -la|grep pexpect:
--------------
ii python-pexpect 3.1-1ubuntu0.1 all Python module for automating interactive applications
--------------

Revision history for this message

Tom Schnittke (ilya-ruprecht) wrote on 2016-04-21:

weird thing is, that is works when is start it interactively

Revision history for this message

Tom Schnittke (ilya-ruprecht) wrote on 2016-04-21:

*facepalm*

Sorry, my fault.

The ssh-key was NOT a default "~/.ssh/id_rsa" but a "~/.ssh/id_rsa_backup"

Thus, the backup-script, that calls hat a line
"ssh-add /root/.ssh/id_rsa_backup" but it had no effect in a noninteractive env, where no ssh-agent was running.

Thus, there was not key for duplicity.

So i'm calling now duplicity with "--ssh-options" -

/usr/bin/duplicity --ssh-options="-oProtocol=2 -oIdentityFile='/root/.ssh/id_rsa_backup'" ....

and everything works fine.

Revision history for this message

Kenneth Loafman (kenneth-loafman) wrote on 2016-04-21:

Glad you found it!