Duplicity with B2 Backblaze issue

I've had this issue, and it was caused by the b2 package splitting into two parts (b2 and b2sdk), and the sdk part (which duplicity relies on) changing its name as a result of this.

Latest duplicity codebase supports both older and newer version of the library, but older versions such as 0.7.18.2 does not.

What fixed this for me was removing duplicity with apt, and installing it with pip instead (I used python3 instead of python2 as python2 is EOL):

sudo apt remove duplicity
sudo apt install build-essential python3-dev gettext librsync-dev
sudo -H pip3 install duplicity

An update:

I learned that the B2 Application key is not supported. I needed to create a Master Application key instead. It did not contain any slashes and I eventually got connected with this result: How to fix Duplicity B2 (Backblaze) error

It says that there is a bug that has been fixed in 0.7.18. According to the reply this is available in a ppa. It seems not in the standard repositories for the 18.04 as I did not get it with sudo apt upgrade.

I faced the same issue. I got with some progress, but not fully resolved the issue. I am running on Ubuntu 18.04 LTS as well. The duplicity version is 0.7.17 (straight from the default repository).

Before installing the pip and adding the b2 I did add (apt install) some other packages that were suggested by the package manager at the time of installing duplicity. Namely: python-pexpect, python-urllib3 and python-oauthlib.

With these installed I run the duplicity again. I do not get the BackendException on B2 Python API any more.

However, I faced another error message (another issue?):

InvalidBackendURL: Syntax error (port) in: b2://xxxxxxxx:YYYYY/yyy@hv-homes/ AFalse BNone xxxxxxxxx:YYYYY

It is perhaps worth mentioning that my application key contains "/" and the error message repeats it until the "/"-sign. I do not know if this error relates to the same B2 API or is something else. At least I do not have a request to install b2 anymore :-)