Molecule 5.0 Failing on GitHub Action

[dgibbs64]

Issue Type

• Bug report

Molecule and Ansible details

ansible --version && molecule --version
ansible-7.4.0
molecule-5.0.0

Molecule installation method (one of):

• pip

Ansible installation method (one of):

• pip

Detail any linters or test runners used:

Desired Behavior

Molecule not failing to run.

Actual Behaviour

Since release of molecule 5.0 my github action is failing with the following error:
https://github.com/dgibbs64/ansible-role-linux_admin_packages/actions/runs/4759492512/jobs/8458829447

Traceback (most recent call last):
File "/home/runner/.local/bin/molecule", line 8, in
sys.exit(main())
File "/usr/lib/python3/dist-packages/click/core.py", line 1128, in call
return self.main(*args, **kwargs)
File "/usr/lib/python3/dist-packages/click/core.py", line 1053, in main
rv = self.invoke(ctx)
File "/usr/lib/python3/dist-packages/click/core.py", line 1659, in invoke
return _process_result(sub_ctx.command.invoke(sub_ctx))
File "/usr/lib/python3/dist-packages/click/core.py", line 1395, in invoke
return ctx.invoke(self.callback, **ctx.params)
File "/usr/lib/python3/dist-packages/click/core.py", line 754, in invoke
return __callback(*args, **kwargs)
File "/usr/lib/python3/dist-packages/click/decorators.py", line 26, in new_func
return f(get_current_context(), *args, **kwargs)
File "/home/runner/.local/lib/python3.10/site-packages/molecule/command/test.py", line 113, in test
base.execute_cmdline_scenarios(scenario_name, args, command_args, ansible_args)
File "/home/runner/.local/lib/python3.10/site-packages/molecule/command/base.py", line 94, in execute_cmdline_scenarios
get_configs(args, command_args, ansible_args, glob_str),
File "/home/runner/.local/lib/python3.10/site-packages/molecule/command/base.py", line 185, in get_configs
configs = [
File "/home/runner/.local/lib/python3.10/site-packages/molecule/command/base.py", line 186, in
config.Config(
File "/home/runner/.local/lib/python3.10/site-packages/molecule/config.py", line 64, in call
obj.after_init()
File "/home/runner/.local/lib/python3.10/site-packages/molecule/config.py", line 116, in after_init
self.config = self._reget_config()
File "/home/runner/.local/lib/python3.10/site-packages/molecule/config.py", line 306, in _reget_config
env = util.merge_dicts(os.environ, self.env)
File "/home/runner/.local/lib/python3.10/site-packages/molecule/config.py", line 201, in env
"MOLECULE_INSTANCE_CONFIG": self.driver.instance_config,
File "/usr/lib/python3.10/functools.py", line 981, in get
val = self.func(instance)
File "/home/runner/.local/lib/python3.10/site-packages/molecule/config.py", line 185, in driver
driver = api.drivers(config=self)[driver_name]
File "/home/runner/.local/lib/python3.10/site-packages/molecule/api.py", line 30, in getitem
return self.dict[i]
KeyError: 'docker'

[kmezynski]

I could have observed the same bug on my GitHub action: https://github.com/kmezynski/ansible-role-ohmyzsh/actions/runs/4756760785/jobs/8452737921. No changes to the role itself were made since last successful build on 19th April. By just looking on the traceback and most recent changes to the molecule's code, I'd start debugging from #3874.

[ssbarnea]

PRs are more than welcomed but support questions should go to discussions. I am not sure if this counts as support or a real bug so I will not move it to discussions yet.

[vitabaks]

oops

https://github.com/vitabaks/postgresql_cluster/actions/runs/4760126337

[ktdreyer]

The original reporter had a GitHub Action that ran pip install molecule[docker]. This no longer works in Molecule 5.0.

The same is true for the podman driver. This used to work:

pip install install molecule[podman]==4.0.4

This no longer works in 5.0.0:

pip install install molecule[podman]==5.0.0
WARNING: molecule 5.0.0 does not provide the extra 'podman'

The replacement is documented:

pip install molecule-plugins[podman]

It would be nice if the error message was clearer instead of simply raising KeyError. If you raise MoleculeDriverNotFound (maybe with a link to the Molecule installation docs) it would be easier for users to search with Google.

[fauust]

I was also impacted by this today and here is a proposition to make it clear in the documentation (#3899).

[apatard]

A crude hack for this would be something like:

--- a/molecule/config.py	2023-04-26 08:12:23.747331357 +0000
+++ b/molecule/config.py	2023-04-26 15:33:04.084062504 +0000
@@ -182,7 +182,12 @@ class Config(metaclass=NewInitCaller):
         driver_name = self._get_driver_name()
         driver = None
 
-        driver = api.drivers(config=self)[driver_name]
+        api_drivers = api.drivers(config=self)
+        if 'driver_name' not in api_drivers:
+            msg = f"Failed to find driver {driver_name}. Maybe missing 'molecule-plugins\[{driver_name}]' ?\n"
+            util.sysexit_with_message(msg)
+
+        driver = api_drivers[driver_name]
         driver.name = driver_name
 
         return driver

This would improve the situation, as a backtrace for missing driver is bad.
@ssbarnea would you accept a PR with this change or is there a better way to do it ?

[dgibbs64]

So to confirm the fix is to change molecule[docker] to molecule-plugins in my github action.

It would be good to have some sort of error message when the failure happens