Only save keys on refresh operation

[kamaradclimber]

When doing a refresh, saving the encrypted secret is useless since
neither the secret, neither the shared key has changed.

Before this patch, the IV was not reused and the encrypted data changed
on each refresh operation.

This improves partially #193 .

[kamaradclimber]

@thommay any thoughs regarding this PR ?

[thommay]

I think it's fine, but I've not had a chance to test it. I'd also like to see some tests, to confirm that we only write the things we need to write, and to confirm that we do write the right things.

[kamaradclimber]

@thommay I've added specs (and rebased against master).

[thommay]

(closed just to get travis to build it)

[kamaradclimber]

tests are failing except on ruby 1.9.3, I am investigating but I doubt this is linked to this patch.

Edit: the features testing fails without my patch.Issue can be tracked down to chef/chef#4602.

[thommay]

Ok, so I fixed the feature tests :) But sadly your tests are still red.

The issue is that ChefVault::Item is a subclass of Chef::DataBagItem, and the #save method calls super(). ( https://github.com/chef/chef-vault/pull/194/files#diff-c71d5d0431f46d4369cef31fe2fef5e2R242 ). With your patch, you're now effectively calling super() on #save_keys and #save_item, neither of which exist in the super class.

[kamaradclimber]

fixed, thanks for your advices

[thommay]

Awesome, thanks