Module: Occi::Core::Helpers::ParserDereferencer

Included in:
Parsers::Json::Category, Parsers::Text::Category
Defined in:
lib/occi/core/helpers/parser_dereferencer.rb

Overview

Introduces dereferencing capabilities to various parsers. This allowes parsers to convert ‘Occi::Core::Category` sub-types from identifier into proper objects.

Author:

Instance Method Summary collapse

Instance Method Details

#dereference_identifiers!(derefd, parsed) ⇒ Array

Dereferences cross-category references. Takes existing string identifiers for actions, mixins, and kinds and replaces them with actual instances.

Parameters:

  • derefd (Array) —

    list of instances needing dereferencing

  • parsed (Array) —

    list of raw parsed categories (as hashes)

Returns:

  • (Array) —

    dereferenced list of instances



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# File 'lib/occi/core/helpers/parser_dereferencer.rb', line 16

def dereference_identifiers!(derefd, parsed)
  derefd.each do |cat|
    next if cat.is_a?(Occi::Core::Action) # nothing to do here
    lookup_references!(cat, derefd, parsed)
  end
  derefd
end

#first_or_die(where, what) ⇒ Object

Returns desired item from ‘where`.

Parameters:

  • where (Enumerable) —

    list of items to look through, items must respond to ‘.identifier`

  • what (String) —

    identifier of the desired item

Returns:

  • (Object) —

    desired item from ‘where`



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# File 'lib/occi/core/helpers/parser_dereferencer.rb', line 87

def first_or_die(where, what)
  logger.debug { "Looking for #{what.inspect} in #{where.class}" }
  found = where.detect { |elm| elm.identifier == what }
  unless found
    raise Occi::Core::Errors::ParsingError,
          "Category #{what.to_s.inspect} referenced but not provided"
  end
  found
end

#lookup_action_references!(cat, derefd, parsed_actions) ⇒ Object

Parameters:

  • cat (Occi::Core::Mixin, Occi::Core::Kind) —

    category instance needing action dereferencing

  • derefd (Array) —

    list of all available category instances

  • parsed_actions (Array) —

    textual representation of needed actions



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# File 'lib/occi/core/helpers/parser_dereferencer.rb', line 46

def lookup_action_references!(cat, derefd, parsed_actions)
  return if parsed_actions.blank?
  logger.debug { "Dereferencing actions #{parsed_actions.inspect} for #{cat.identifier.inspect}" }
  parsed_actions.each { |action| cat.actions << first_or_die(derefd, action) }
end

#lookup_applies_references!(_mixin, _derefd, _parsed_rel) ⇒ Object

Parameters:

  • mixin (Occi::Core::Mixin) —

    mixin instance needing applicability dereferencing

  • derefd (Array) —

    list of all available category instances

  • parsed_rel (Array) —

    textual representations of needed applicability targets

Raises:



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# File 'lib/occi/core/helpers/parser_dereferencer.rb', line 73

def lookup_applies_references!(_mixin, _derefd, _parsed_rel)
  raise Occi::Core::Errors::ParserError, 'Must be implemented in the parser class'
end

#lookup_depends_references!(_mixin, _derefd, _parsed_rel) ⇒ Object

Parameters:

  • mixin (Occi::Core::Mixin) —

    mixin instance needing dependency dereferencing

  • derefd (Array) —

    list of all available category instances

  • parsed_rel (Array) —

    textual representations of needed dependencies

Raises:



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# File 'lib/occi/core/helpers/parser_dereferencer.rb', line 80

def lookup_depends_references!(_mixin, _derefd, _parsed_rel)
  raise Occi::Core::Errors::ParserError, 'Must be implemented in the parser class'
end

#lookup_parent_references!(kind, derefd, parsed_rel) ⇒ Object

Parameters:

  • kind (Occi::Core::Kind) —

    kind instance needing parent dereferencing

  • derefd (Array) —

    list of all available category instances

  • parsed_rel (Array) —

    textual representation of needed parent(s)



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# File 'lib/occi/core/helpers/parser_dereferencer.rb', line 55

def lookup_parent_references!(kind, derefd, parsed_rel)
  return if parsed_rel.blank? || kind.parent.is_a?(Occi::Core::Kind)
  logger.debug { "Dereferencing parent #{parsed_rel.inspect} for #{kind.identifier.inspect}" }
  if parsed_rel.is_a?(Enumerable)
    if parsed_rel.count > 1
      raise Occi::Core::Errors::ParsingError,
            "Kind #{kind} with multiple parents #{parsed_rel.inspect}"
    end
    parsed_rel = parsed_rel.first
  end

  kind.parent = first_or_die(derefd, parsed_rel)
  kind.send(:load_parent_attributes!) # this is safe because there was no previous parent!
end

#lookup_references!(cat, derefd, parsed) ⇒ Object

Looks up inter-category references and replaces them with existing objects.

Parameters:

  • cat (Occi::Core::Mixin, Occi::Core::Kind) —

    category to dereference

  • derefd (Array) —

    list of known categories

  • parsed (Array) —

    list of original parsed category structures

Raises:



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# File 'lib/occi/core/helpers/parser_dereferencer.rb', line 29

def lookup_references!(cat, derefd, parsed)
  parsed_cat = parsed.detect { |pcat| "#{pcat[:scheme]}#{pcat[:term]}" == cat.identifier }
  raise Occi::Core::Errors::ParsingError, "Category #{cat.identifier} not in the model" unless parsed_cat
  lookup_action_references!(cat, derefd, parsed_cat[:actions])

  if cat.is_a?(Occi::Core::Mixin)
    lookup_depends_references!(cat, derefd, parsed_cat[self::DEPENDS_KEY])
    lookup_applies_references!(cat, derefd, parsed_cat[self::APPLIES_KEY])
  else
    # only Occi::Core::Kind is left here
    lookup_parent_references!(cat, derefd, parsed_cat[self::PARENT_KEY])
  end
end