Mopidy cannot find gstreamer, even though installed per instructions

Q&A
1

I’m running Gentoo on a Raspberry Pi, and all dependencies have been installed per the install instructions.

I’m running inside a virtual environment to keep it from stepping on system installs, and when I do run it, I get the following:

((mopidy) ) digitech ~/mopidy # mopidy
/root/mopidy/lib/python3.12/site-packages/mopidy/init.py:5: UserWarning: pkg_resources is deprecated as an API. See Package Discovery and Resource Access using pkg_resources - setuptools 80.9.0 documentation. The pkg_resources package is slated for removal as early as 2025-11-30. Refrain from using this package or pin to Setuptools<81.
import pkg_resources

ERROR: A GObject based library was not found.

Mopidy requires GStreamer to work. GStreamer is a C library with a
number of dependencies itself, and cannot be installed with the regular
Python tools like pip.

Please see Installation — Mopidy 4.0.0a5.dev16+g149e8af documentation for
instructions on how to install the required dependencies.

Traceback (most recent call last):
File “/root/mopidy/bin/mopidy”, line 5, in
from mopidy.main import main
File “/root/mopidy/lib/python3.12/site-packages/mopidy/main.py”, line 7, in
from mopidy import commands
File “/root/mopidy/lib/python3.12/site-packages/mopidy/commands.py”, line 18, in
from mopidy.audio import Audio
File “/root/mopidy/lib/python3.12/site-packages/mopidy/audio/init.py”, line 2, in
from .actor import Audio
File “/root/mopidy/lib/python3.12/site-packages/mopidy/audio/actor.py”, line 8, in
from mopidy.audio import tags as tags_lib
File “/root/mopidy/lib/python3.12/site-packages/mopidy/audio/tags.py”, line 7, in
from mopidy.internal.gi import GLib, Gst
File “/root/mopidy/lib/python3.12/site-packages/mopidy/internal/gi.py”, line 5, in
import gi
ModuleNotFoundError: No module named ‘gi’

But the packages are there:
dev-python/gst-python-1.24.11
media-libs/gst-plugins-base-1.24.11
media-libs/gst-plugins-good-1.24.11
media-libs/gst-plugins-ugly-1.24.11
media-libs/gstreamer-1.24.11
media-plugins/gst-plugins-meta-1.24.11
media-plugins/gst-plugins-mpeg2dec-1.24.11
media-plugins/gst-plugins-mpg123-1.24.11
dev-libs/gobject-introspection-1.82.0-r2

Thoughts?

2

What does “there” mean here? Also AFAIU the list you produce isn’t about Python packages, but the error is that a Python module is missing… The error is explicit: There’s no gi module in the virtual environment.

One easy solution is to install the corresponding operating system package and activate the include-system-site-packages at creation of the virtual environment, so that system packages are found by the virtual environment Python interpreter as fallback.

Under a Debian host:

$ sudo apt install -y python3-gi
$ python -m venv --sitem-site-packages mopidy-env

An alternative is to install the Python package in the virtual environment but unless it’s available as a “wheel” matching your Python interpreter, libc version, processor architecture, etc. prepare to have to compile a lot of things…

3

I found that suggestion re: that include in another thread regarding a different Python issue, and I’m trying that.

Hopefully it will see gstreamer now.

4

It did, all good. This can be closed.