How can I generate the metadata.json file From metadata.rb?

Background Information

You have made changes to your Chef cookbook in the metadata.rb file and need to generate or regenerate metadata.json.

Important! As of the 2013-10-01 Dashboard release you no longer have to manually generate a cookbook's metadata.json file because RightScale automatically creates the metadata.json file (from the metadata.rb file) upon a fetch or refetch of your cookbooks into Repose. See Chef Metadata for more technical details.

Answer

There are two tools to facilitate this process—knife or rake. Using knife is the preferred method.

Update Metadata with Knife (Preferred Method)

Knife is included in the chef RubyGem. You can still install Chef without configuring the node for chef-client or chef-server to obtain knife:

gem install chef

Re-generate metadata.json by pointing to the cookbooks path and specifying the cookbook to update. This example updates a cookbook called munchies residing in ~/chef-cookbooks/cookbooks:

knife cookbook metadata munchies -o ~/chef-cookbooks/cookbooks

For more information on how you can use Knife to manage your cookbooks, run the command knife --help.

Update Metadata with Rake (Additional Method)

Chef comes with a metadata Rake task to generate the metadata.json file.

In your Chef repository, run the following command to update the metadata.json for all cookbooks:

rake metadata

Or, use the cookbook parameter to target a specific cookbook (e.g., db_mysql):

rake metadata cookbook=db_mysql

This is a Ruby command and requires that the rake RubyGem is installed. To install the rake gem, run the following command:

gem install rake