set an attribute on the node

gistfile1.rb

# Knife plugin to set an attribute on the node
# Usage:
# $knife node exec [nodename] 'node.set[:somevalue] = true'

class NodeExec < Chef::Knife
  banner "knife node exec NODE CODE (options)"

  deps do
    require 'chef/search/query'
  end

  def run
    if name_args.size == 2
      node_name = name_args.first
      code = name_args.last
    else
      ui.fatal "Please provide a node name & code"
      exit 1
    end
    q = Chef::Search::Query.new
    q.search('node', "name:#{node_name}") do |node|
      if node.run_list.empty?
        ui.warn("#{node.name}'s run list is empty.")
        exit 1
      end
      ui.msg("The following piece of code will be executed against node #{node_name}:")
      ui.output(code)
      ui.confirm("Are you sure?")
      ui.output eval(code)
      node.save
    end
  end
end