Ubuntu – “Backups” (deja-dup): after installing duplicity 0.8 from source, “Backups” can’t find it

backupdeja-dupduplicitygnomerestore

When using "Backups" (a.k.a. deja-dup) – it doesn't find duplicity, although it's installed:

I have been trying to backup using "Backups" (a.k.a. deja-dup), and it turns out that the current duplicity (which deja-dup uses) still has the "Unicode bug" (it fails when dealing with Unicode strings).
(I have "Backups" (a.k.a. deja-dup) installed on my system: "deja-dup backup tool" v 37.0, and had duplicity v 0.7.17).

My system: 

~$ lsb_release -a
Description:   Ubuntu 18.04.3 LTS; Release:  18.04; Codename:   bionic

So, I then removed the existing installation of duplicity, and installed duplicity 0.8 from source: https://launchpad.net/duplicity. It installs duplicity at: /usr/local/bin. It's in PATH:

~$ echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin

After loading and installing all the requirements, duplicity 0.8 itself runs fine:

~$ duplicity -V
duplicity 0.8.05

But, when running "Backups" (deja-dup), it doesn't find it. A window pops up, saying:

INSTALL PACKAGES

In order to continue, the following package needs to
be installed: duplicity

I installed dconf-editor, found /org/gnome/deja-dup, but I don't see there any settings for the duplicity path.

nautilus and "apt list –installed" don't see it, either.

Note: cross posted here

Best Answer

If Deja-Dup does check for duplicity package instead of command, you may try faking a Debian package like in this case MySQL 5.6 depends on client 5.5 , which is about a dependency issue.

equivs may help to create dummy packages.

  1. Install equivs:

    sudo apt-get install equivs

  2. Generate control file from template:

    equivs-control duplicity

  3. Open duplicity file for edit. Change name and version if needed:

    ...
Package: duplicity
Version: 0.8.05
...

  4. Build then install it:

    equivs-build duplicity
sudo dpkg -i duplicity*.deb

Notes:

  • It can be uninstalled like any package. If you are using this method on large scale (company computers), write something in description (step 3) to indicate it's a dummy/fake package.
  • For general case, some packages have Provides:.. field, check original package and copy that line from its control file, add it with step (3).
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