Module: Puppet::Util::PsychSupport

Included in:
Indirector::Request, Node, Node::Facts, Resource::Status, Log
Defined in:
lib/puppet/util/psych_support.rb

Overview

This module should be included when a class can be serialized to yaml and needs to handle the deserialization from Psych with more control. Psych normall pokes values directly into an instance using ‘instance_variable_set` which completely bypasses encapsulation.

The class that includes this module must implement an instance method ‘initialize_from_hash` that is given a hash with attribute to value mappings.

Instance Method Summary collapse

Instance Method Details

#encode_with(psych_encoder) ⇒ Object

This method is called from the Psych Yaml serializer The serializer will call this method to create a hash that will be serialized to YAML. Instead of using the object itself during the mapping process we use what is returned by calling ‘to_data_hash` on the object itself since some of the objects we manage have asymmetrical serialization and deserialization.



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# File 'lib/puppet/util/psych_support.rb', line 30

def encode_with(psych_encoder)
  tag = Psych.dump_tags[self.class]
  unless tag
    klass = self.class == Object ? nil : self.class.name
    tag   = ['!ruby/object', klass].compact.join(':')
  end
  psych_encoder.represent_map(tag, to_data_hash)
end

#init_with(psych_coder) ⇒ Object

This method is called from the Psych Yaml deserializer. The serializer calls this instead of doing the initialization itself using ‘instance_variable_set`. The Status class requires this because it serializes its TagSet as an `Array` in order to optimize the size of the serialized result. When this array is later deserialized it must be reincarnated as a TagSet. The standard Psych way of doing this via poking values into instance variables cannot do this.



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# File 'lib/puppet/util/psych_support.rb', line 17

def init_with(psych_coder)
  # The PsychCoder has a hashmap of instance variable name (sans the @ symbol) to values
  # to set, and can thus directly be fed to initialize_from_hash.
  #
  initialize_from_hash(psych_coder.map)
end