Module: OmfRc::ResourceProxyDSL::ClassMethods

Examples:

module OmfRc::Util::Iw
  include OmfRc::ResourceProxyDSL

  configure :freq do |resource, value|
    `iw #{resource.hrn} set freq #{value}`
    "Frequency set to #{value}"
  end

  # or use iterator to define multiple properties
  %w(freq channel type).each do |p|
    configure p do |resource, value|
      `iw #{resource.hrn} set freq #{value}`
    end
  end

  # or we can try to parse iw's help page to extract valid properties and then automatically register them
  `iw help`.chomp.gsub(/^\t/, '').split("\n").map {|v| v.match(/[phy|dev] <.+> set (\w+) .*/) && $1 }.compact.uniq.each do |p|
    configure p do |resource, value|
      `iw #{resource.hrn} set #{p} #{value}`
    end
  end
end

Examples:

configure_all do |resource, configure_properties, result|
  # Execute property one first, and make sure it is successful before attending property two
  if resource.some_operation(configure_properties[:property_one])
    if resource.other_operation(configure_properties[:property_two])
      result[:property_one] = 'GOOD'
      result[:property_two] = 'GREAT'
    else
      raise "Some errors"
    end
  else
    raise "Some errors"
  end
end

Examples:

configure :bob do |resource, value|
  resource.property.bob = value
end

# To extend this, simply do

extend_configure :bob

configure :bob do |resource, value|
  resource.orig_configure_bob(value)
  resource.property.bob = "New value: #{value}"
end

Examples:

# suppose existing hook defined as this:
hook :before_ready do |resource|
  logger.info "I am ready"
end

# now in a new proxy where we want to extend this hook, add more functionality:

extend_hook :before_ready

hook :before_ready do |resource|
  resource.orig_before_ready

  logger.info "Now I am really ready"
end

# if we simply want to overwrite the existing hook, just define the same hook without using extend_hook

hook :before_ready do |resource|
  logger.info "Not sure if I am ready or not"
end

Examples:

module OmfRc::ResourceProxy::Node
 include OmfRc::ResourceProxyDSL

 register_proxy :node

 # before_create hook
 #
 # the optional block will have access to three variables:
 # * resource: the parent resource itself
 # * new_resource_type: a string or symbol represents the new resource to be created
 # * new_resource_options: the options hash to be passed to the new resource
 #
 # this hook enable us to do things like:
 # * validating child resources: e.g. if parent could create this new resource
 # * setting up default child properties based on parent's property value
 hook :before_create do |resource, new_resource_type, new_resource_options|
   if new_resource_type.to_sym == :wifi
     logger.info "Resource type wifi is allowed"
   else
     raise "Go away, I can't create #{new_resource_type}"
   end
   new_resource_options.property ||= Hashie::Mash.new
   new_resource_options.property.node_info = "Node #{resource.uid}"
 end

 # after_create hook
 #
 # the optional block will have access to these variables:
 # * resource: the parent resource itself
 # * new_resource: the child resource instance
 hook :after_create do |resource, new_resource|
   logger.info "#{resource.uid} created #{new_resource.uid}"
 end

 # before_ready hook
 #
 # the optional block will have access to resource instance. Useful to initialise resource
 hook :before_ready do |resource|
   logger.info "#{resource.uid} is now ready"
 end

 # before_release hook
 #
 # the optional block will have access to resource instance. Useful to clean up resource before release it.
 hook :before_release do |resource|
   logger.info "#{resource.uid} is now released"
 end

 # after_initial_configured hook
 #
 # the optional block will have access to resource instance. Useful for actions depends on certain configured property values.
 hook :after_initial_configured do |resource|
   logger.info "#{resource.uid} has an IP address" unless resource.request_ip_addr.nil?
 end
end

Examples:

# Read-only property, i.e. could not be modified through FRCP protocol
property :bob, default: 1, access: :read_only

# Read & Write property, i.e. could be modified through FRCP protocol
property :bob, default: 1, access: :configure

# Read & could be modified ONLY through FRCP CREATE message
property :bob, default: 1, access: :init_only

Examples:

module OmfRc::ResourceProxy::Wifi
  include OmfRc::ResourceProxyDSL

  # Let the factory know it is available
  register_proxy :wifi

  # or use option :create_by
  register_proxy :wifi, :create_by => :node
end

Examples:

module OmfRc::Util::Iw
  include OmfRc::ResourceProxyDSL

  request :freq do |resource|
    `iw #{resource.hrn} link`.match(/^(freq):\W*(.+)$/) && $2
  end

  # or we can grab everything from output of iw link command and return as a hash(mash)
  `iw #{resource.hrn} link`.chomp.gsub(/^\t/, '').split("\n").drop(1).each do |v|
    v.match(/^(.+):\W*(.+)$/).tap do |m|
      m && known_properties[m[1].downcase.gsub(/\W+/, '_')] = m[2].gsub(/^\W+/, '')
    end
  end
end

Examples:

module OmfRc::ResourceProxy::Wifi
  include OmfRc::ResourceProxyDSL

  # Simply include this util module
  utility :iw
end

Examples:

work :os do
  `uname`
end

# then this os method will be available in all proxy definitions which includes this work method definition.
# if for some reason you need to call 'os' method within the same module, you need to access it via the resource instance.

work :install_software do |resource|
  raise 'Can not support non-linux distro yet' if resource.os == 'Linux'
end