non-functional attempt at a swapfile provider for chef

swapfile.rb

#
# Provider Name:: swapfile
#
# Copyright 2010, Blue Coat Systems Inc.
#

require 'chef/mixin/command'
include Chef::Mixin::Command

action :create do
  unless @swap.exists
    execute "/bin/dd if=/dev/zero of= bs=1 count=#{params[:size]}"




  if File.exist?("#{params[:name]}")
    if File.size?("#{params[:name]}") == params[:size]
      Chef::Log.debug "Existing size of #{params[:name]} already matches desired swapfile size of #{params[:size]}"
      new_resource.updated = false
    else
      if system("/bin/swapoff #{params[:name]}")
        Chef::Log.info "Creating swapfile at #{params[:name]}"
        if system("/bin/dd if=/dev/zero of=#{params[:name]} bs=1 count=#{params[:size]}") 
          if system("/sbin/mkswap #{params[:name]}")
            if system("/usr/local/bin/fstab-update")
                new_resource.updated = true
            else
               Chef::Log.info "Failed to update /etc/fstab using fstab-update"
            end
          else
            Chef::Log.info "Failed to execute mkswap against #{params[:name]}"
            new_resource.updated = false
          end
        else
          Chef::Log.info "Failed to create swapfile of size #{params[:size]} at #{params[:name]}"
          new_resource.updated = false
        end
      else
        Chef::Log.info "Failed to swapoff #{params[:name]} for swapfile resizing. No action taken."
        new_resource.updated = false
      end
    end
  else
    Chef::Log.info "Creating swapfile at #{params[:name]}"
    system("/bin/dd if=/dev/zero of=#{params[:name]} bs=1M count=#{params[:size]}")
    new_resource.updated = true
  end
end

#action :delete do
#  if File.exist?("#{params[:name]}") 
#    if system("/bin/swapoff #{params[:name]}")
#      if File.delete("#{params[:name]}")
#         Chef::Log.info "Deleting swapfile at #{params[:name]}"
#         new_resource.updated = true
#      else
#        Chef::Log.info "Failed to delete swapfile at #{params[:name]}"
#        new_resource.updated = false
#      end
#    else
#      Chef::Log.info "You asked me to delete a swapfile at #{params[:name]} but I could not swapoff that file."
#      new_resource.updated = false
#    end
#  else
#    Chef::Log.info "You asked me to delete a swapfile at #{params[:name]} but the specified file does not exist. No action taken."
#    new_resource.updated = false
#  end
#end

def load_current_resource
  @swap = Chef::Resource::Swapfile.new(new_resource.swap_name)
  @swap.swap_name(new_resource.swap_name)

  Chef::Log.debug("Checking for existing swap file #{new_resource.swap_name}")

  begin
    if File.exist?("#{new_resource.swap_name}") 
      @swap.exists(true)
    end
  rescue Chef::Exceptions::Exec
    @swap.exists(false)
    nil
  end

  Chef::Log.debug("Checking size of existing swap file #{new_resource.swap_name}")

  begin
    if @swap.exists
      @swap.size(File.size("#{new_resource.swap_name}"))
    end
  rescue Chef::Exceptions::Exec
    @swap.size(nil)
    nil
  end

  Chef::Log.debug("Checking status of swap file #{new_resource.swap_name}")

  begin
    if @swap.exists
      if system("/bin/swapon -s | grep #{new_resource.swap_name}")
        @swap.enabled(true)
      end
    end
   rescue Chef::Exceptions::Exec
     @swap.enabled(false)
     nil
   end
end