Amazon S3 fails with "BackendException: Boto requires a bucket name."

[Michael Fötsch]

After upgrade to 15.04 vivid, backup and restore to/from Amazon S3 fail with the error: "BackendException: Boto requires a bucket name."

$ lsb_release -d
Description: Ubuntu 15.04

$ dpkg-query -W deja-dup duplicity python-boto
deja-dup 32.0-0ubuntu5
duplicity 0.7.01-1ubuntu1
python-boto 2.34.0-2ubuntu1

$ gsettings list-recursively org.gnome.DejaDup
org.gnome.DejaDup last-restore '2012-07-20T01:36:34.059723Z'
org.gnome.DejaDup periodic true
org.gnome.DejaDup full-backup-period 90
org.gnome.DejaDup backend 's3'
org.gnome.DejaDup last-run '2015-04-30T14:57:25.003773Z'
org.gnome.DejaDup nag-check '2015-04-16T10:06:50.795593Z'
org.gnome.DejaDup prompt-check '2012-07-19T22:57:00.059764Z'
org.gnome.DejaDup root-prompt true
org.gnome.DejaDup include-list ['$HOME']
org.gnome.DejaDup exclude-list ['/home/mmm/Videos']
org.gnome.DejaDup last-backup '2015-04-30T14:57:25.003773Z'
org.gnome.DejaDup periodic-period 7
org.gnome.DejaDup delete-after 84
org.gnome.DejaDup.S3 id '<S3 ID>'
org.gnome.DejaDup.S3 bucket 'deja-dup-auto-<S3 ID>'
org.gnome.DejaDup.S3 folder ''

$ DEJA_DUP_DEBUG=1 deja-dup --backup | tail -n 1000 > /tmp/deja-dup.log
$ cat /tmp/deja-dup.log
DUPLICITY: INFO 1
DUPLICITY: . Using archive dir: /home/mmm/.cache/deja-dup/ea4c35ee6036c3a1026043e933e9969c
DUPLICITY: INFO 1
DUPLICITY: . Using backup name: ea4c35ee6036c3a1026043e933e9969c
DUPLICITY: INFO 1
DUPLICITY: . Import of duplicity.backends.azurebackend Succeeded
DUPLICITY: INFO 1
DUPLICITY: . Import of duplicity.backends.botobackend Succeeded
...
DUPLICITY: INFO 1
DUPLICITY: . Using temporary directory /tmp/duplicity-gGMHgw-tempdir
DUPLICITY: INFO 1
DUPLICITY: . Backend error detail: Traceback (most recent call last):
DUPLICITY: . File "/usr/bin/duplicity", line 1500, in <module>
DUPLICITY: . with_tempdir(main)
DUPLICITY: . File "/usr/bin/duplicity", line 1494, in with_tempdir
DUPLICITY: . fn()
DUPLICITY: . File "/usr/bin/duplicity", line 1327, in main
DUPLICITY: . action = commandline.ProcessCommandLine(sys.argv[1:])
DUPLICITY: . File "/usr/lib/python2.7/dist-packages/duplicity/commandline.py", line 1047, in ProcessCommandLine
DUPLICITY: . globals.backend = backend.get_backend(args[0])
DUPLICITY: . File "/usr/lib/python2.7/dist-packages/duplicity/backend.py", line 221, in get_backend
DUPLICITY: . obj = get_backend_object(url_string)
DUPLICITY: . File "/usr/lib/python2.7/dist-packages/duplicity/backend.py", line 207, in get_backend_object
DUPLICITY: . return factory(pu)
DUPLICITY: . File "/usr/lib/python2.7/dist-packages/duplicity/backends/_boto_single.py", line 145, in __init__
DUPLICITY: . raise BackendException('Boto requires a bucket name.')
DUPLICITY: . BackendException: Boto requires a bucket name.
DUPLICITY: .
DUPLICITY: ERROR 23 BackendException
DUPLICITY: . BackendException: Boto requires a bucket name.

[Michael Fötsch (foetsch)]

This is caused by duplicity bug #1411803, which has been patched but is not in vivid as of yet.