deprecated/deferred import for webdav.interfaces.IFTPAccess

[ewohnlich]

Originally reported at
https://community.plone.org/t/zodbupdate-modulenotfounderror-no-module-named-webdav-interfaces/10480

This deprecated import https://github.com/zopefoundation/Zope/blob/master/src/OFS/interfaces.py#L1059 is a problem because the top level webdav module is moved to ZServer. The latest ZServer is not compatible with python 3.

The problem manifested for me when trying to use zodbupdate to migrate my ZODB from python 2 to python 3. The deprecated import here seems to preclude using plone.app.upgrade's alias_module function to simulate deprecated modules, and letting it resolve to ZServer/webdav is not an option because that package is not compatible with python 3. My solution was to just edit OFS/interfaces.py and remove that deprecated import.

[dataflake]

@ewohnlich Would you mind trying out that test migration with the Zope code from the issue_714 branch? I don't have any Plone setup available for this.

[ewohnlich]

@dataflake We tested this change and it worked as expected, thanks!

[dataflake]

@ewohnlich Thanks for helping test that. I'll merge the PR and will release Zope 4.1.3 some time this coming weekend.

[dataflake]

Fixed by 3115525