    # File lib/fog/rackspace/requests/compute_v2/update_metadata.rb, line 5
            def update_metadata(collection, obj_id, metadata = {})
              request(
                :expects => [200, 203],
                :method => 'POST',
                :path => "/#{collection}/#{obj_id}/metadata",
                :body => Fog::JSON.encode('metadata' => metadata)
              )
            end