Fix classifier parsing in python 3.8 / python 3.9

[a1lu]

The classifier parser did not work as expected on my machine.

In python3.8 and python3.9 the type email.message import Message is used as metadata type and the metadata are stored in i_metadata._headers as a list of tuples. To iterate over the classifiers in this list of tuples

for classifier in i_metadata['Classifier']:

was used. Though this loop iterates only over the first classifiers characters and not over all classifiers, so the classifiers were never parsed.

I propose in this commit to generate a list of classifiers for python3.8/python3.9 and python3.10 separately and loop over the list of classifiers.

Please note:
I created this PR on github web, I guess the commit message needs to be adjusted before merging!

[jkowalleck]

Could you add proper (unit or integration) tests to prove that your changes actually work?
The tests will be running on CI with every supported python version on every operating system.

Additionally, could you please sign your commit according to https://github.com/CycloneDX/cyclonedx-python/pull/431/checks?check_run_id=9224681013 ?

[jkowalleck]

thank you for the pull request, @a1lu .

please follow https://github.com/CycloneDX/cyclonedx-python/blob/master/CONTRIBUTING.md

I set your pull-request to "draft" state, as this PR is not ready for review.

[a1lu]

Could you add proper (unit or integration) tests to prove that your changes actually work? The tests will be running on CI with every supported python version on every operating system.

Sure, Unfortunately I have only access to the github web IDE right now. I can do this probably during this week.

[a1lu]

I added tests to check if both license entries are present. One from the license field and one from the classifiers.

Also I changed the classifier generation, as I discovered that the python3.10 version did not work on poetry run tox. No all versions use the same generator and the tests pass. Though I need to give mypy a hint to not generate an error.

I am going to squash the commits later (I am still only on github web IDE) and sign the commit.

[jkowalleck]

Thanks for the code, @a1lu

could you sign your commits according to https://github.com/CycloneDX/cyclonedx-python/pull/431/checks?check_run_id=9242986125
to signal that you are providing your code under the projects licenses?

[jkowalleck]

@madpah please review this PR :D

[a1lu]

@jkowalleck I squashed my commits and signed them.

Do we also want to parse the license file metadata entry? Or use the get function for "Author" and "License" too? I could try to implement this in new PR.

[jkowalleck]

@jkowalleck I squashed my commits and signed them.

great 👍

---

Do we also want to parse the license file metadata entry? Or use the get function for "Author" and "License" too?

I would suggest to open an individual issue for each one of these topics, so we could discuss the need, the details and everything.