collective.recipe.zope2install needs better diagnostics when dealing with bad Zope tarball
If there's a transient error or an interruption of the execution of the collective.
Restarting the buildout results in the recipe discovering the partial tarball, which then attempts to extract it, resulting in a stack trace:
An internal error occurred due to a bug in either zc.buildout or in a recipe being used
Traceback (most recent call last):
raise IOError, "CRC check failed"
IOError: CRC check failed
Users, unaware of any issue, may repeatedly re-try the buildout to no avail. Deleting the partial tarball is the only way to make progress, but Buildout newbies may not realize there is even a "downloads" directory or a download cache specified elsewhere by a particular buildout or user default.cfg file.
Better diagnostics would certainly help. And we could provide excellent diagnostics by including an md5sum as an option to the recipe: it could flag a bad or partial tarball instantly.