Add metadata.json support in cookbooks

[kamaradclimber]

Berkshelf vendors cookbooks with compiled metadata file (in json) instead of metadata.rb. We test for both and prefer rb format

fixes bmarini/knife-inspect#5

[gregkare]

I'm going to try to refactor that code, it was already a mess before. We should be able to use classes from Chef to avoid reinventing the wheel. Thanks for the pull request!

[kamaradclimber]

@gregkare agreed that some of this code duplicate chef code

[gregkare]

Here's what I came up with:

      def local_items
        cl = Chef::CookbookLoader.new(@context.cookbook_path)
        cl.load_cookbooks

        cl.inject({}) do |hash, (name, cookbook_version)|
          hash[name] = Chef::Version.new(cookbook_version.version)

          hash
        end
      end

It still passes the tests, now checking how it behaves when there's both a json and rb file

[gregkare]

It loads the metadata.rb first when it exists, nice. Do you want to rebase your pull request to do this instead? I'm always happy to see some code get deleted :)

Edit: Chef::CookbookLoader exists in Chef 10 too, so it should work there too

[kamaradclimber]

https://github.com/opscode/chef/blob/master/lib/chef/cookbook/cookbook_version_loader.rb#L107

rb first, then json, then a new object that I didn't know about: uploaded_cookbook_version_file

[kamaradclimber]

this PR can be closed then

[gregkare]

Ok, I'll do a pull request then, I've also used a metadata.json file in spec/chef-repo/cookbooks/cookbook_two. Thanks!