storage: add depth parameter to LinkStorage

[slint]

• Adds a "depth" parameter to the LinkStorage class which allows
  deciding the max depth at which symlinks will be created up to.

[ThiefMaster]

Hey, nothing wrong with dropping support for old Python versions, but silently doing so in a point release without so much as a changelog entry (and proper python_requires restrictions!) isn't cool... 😞

[slint]

Oh God, you're right I got in "auto"-mode and I didn't even think about it :S. We've been soft-dropping Python 2 support (i.e. removing from the Travis build) in most Invenio modules in the past months.

But the intent is not to actually if possible keep Python 2 compatibility if it's easy. I can remove the os.scandir call in a v1.0.3 release. I wouldn't yet add a python_requires since I think that would then prevent anyone from installing the package with Python 2 (even if it works).

[ThiefMaster]

I wouldn't yet add a python_requires since I think that would then prevent anyone from installing the package with Python 2 (even if it works).

It's indeed too late for this, since you'd have to yank 1.0.2 and 1.0.3 for it to be efficient. My recommendation would be to release 1.0.4 that restores Python 2.7 support (ie no yield from). Since dropping 2.7 support in a point release could be considered a bug I think this is reasonable.

In whatever future release (2.0.0?) you explicitly drop 2.7 again, you can then add the python_requires metadata to ensure this version is not offered to unsupported versions. That way pip list --outdated also won't show it as an update if it's not supported by the current python version.

We've been soft-dropping Python 2 support (i.e. removing from the Travis build)

At least for small libraries like this one I would recommend keeping it there until you explicitly drop it (ie actualy break python 2.7 compatibility).

[lnielsen]

Sorry about the mishap - I didn't realise that Indico was on Python 2.7.

We didn't consider dropping Python 2.7 tests (and thereby Python 2.7 support) as a feature change simply because of the End-Of-Life of Python 2.7, and that we implemented a policy in Invenio of not supporting unsupported Python versions. As Alex said, the intention though was not to start breaking Python 2 compatibility this fast :-)