nautobot-dev (final-dev) docker image doesn't start

[joewesch]

Environment

• Nautobot version (Docker tag too if applicable): 1.4.2 -> latest
• Python version: 3.7 -> 3.10
• Database platform, version: n/a
• Middleware(s): n/a

Steps to Reproduce

1. docker run --rm -it ghcr.io/nautobot/nautobot-dev:1.4.7-py3.10

Expected Behavior

Nautobot Dev should start up

Observed Behavior

Traceback (most recent call last):
  File "/usr/local/lib/python3.10/site-packages/nautobot/extras/plugins/utils.py", line 64, in load_plugin
    plugin = importlib.import_module(plugin_name)
  File "/usr/local/lib/python3.10/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1050, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1004, in _find_and_load_unlocked
ModuleNotFoundError: No module named 'example_plugin'

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/local/lib/python3.10/site-packages/nautobot/core/runner/runner.py", line 116, in settings_callback
    initializer(
  File "/usr/local/lib/python3.10/site-packages/nautobot/core/cli.py", line 176, in _configure_settings
    load_plugins(settings)
  File "/usr/local/lib/python3.10/site-packages/nautobot/extras/plugins/utils.py", line 54, in load_plugins
    load_plugin(plugin_name, settings)
  File "/usr/local/lib/python3.10/site-packages/nautobot/extras/plugins/utils.py", line 67, in load_plugin
    raise PluginNotFound(
nautobot.extras.plugins.exceptions.PluginNotFound: Unable to import plugin example_plugin: Module not found. Check that the plugin module has been installed within the correct Python environment.

[glennmatthews]

Thanks for the report! Hypothesis:

• example_plugin is copied in under /source/examples/example_plugin and installed in the dependencies-dev-python target in editable mode
• both dev and final-dev targets use development/nautobot_config.py as their Nautobot config file, which includes the example plugin
• dev (what we use for Nautobot core development) works just fine this way.
• final-dev (what we publish as nautobot-dev) removes everything under the /source directory, breaking the editable installation of the example plugin.

Possible solutions:

• for final-dev, build the example plugin as a wheel and install it as non-editable so that the removal of /source doesn't impact it?
• for final-dev, use a different nautobot_config.py that doesn't include the example plugin?