Module: CollectiveIdea::Acts::NestedSet::Model::ClassMethods

Defined in:
lib/awesome_nested_set/awesome_nested_set.rb

Instance Method Summary collapse

Instance Method Details

#all_roots_valid? ⇒ Boolean

Wrapper for each_root_valid? that can deal with scope.

Returns:

  • (Boolean) 


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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 161

def all_roots_valid?
  if acts_as_nested_set_options[:scope]
    roots.group_by {|record| scope_column_names.collect {|col| record.send(col.to_sym) } }.all? do |scope, grouped_roots|
      each_root_valid?(grouped_roots)
    end
  else
    each_root_valid?(roots)
  end
end

#associate_parents(objects) ⇒ Object 



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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 272

def associate_parents(objects)
  if objects.all?{|o| o.respond_to?(:association)}
    id_indexed = objects.index_by(&:id)
    objects.each do |object|
      if !(association = object.association(:parent)).loaded? && (parent = id_indexed[object.parent_id])
        association.target = parent
        association.set_inverse_instance(parent)
      end
    end
  else
    objects
  end
end

#each_root_valid?(roots_to_validate) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 171

def each_root_valid?(roots_to_validate)
  left = right = 0
  roots_to_validate.all? do |root|
    (root.left > left && root.right > right).tap do
      left = root.left
      right = root.right
    end
  end
end

#each_with_level(objects) ⇒ Object

Iterates over tree elements and determines the current level in the tree. Only accepts default ordering, odering by an other column than lft does not work. This method is much more efficent than calling level because it doesn’t require any additional database queries.

Example:

Category.each_with_level(Category.root.self_and_descendants) do |o, level|



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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 226

def each_with_level(objects)
  path = [nil]
  objects.each do |o|
    if o.parent_id != path.last
      # we are on a new level, did we descend or ascend?
      if path.include?(o.parent_id)
        # remove wrong wrong tailing paths elements
        path.pop while path.last != o.parent_id
      else
        path << o.parent_id
      end
    end
    yield(o, path.length - 1)
  end
end

#leaves ⇒ Object 



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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 122

def leaves
  where("#{quoted_right_column_full_name} - #{quoted_left_column_full_name} = 1").order(quoted_left_column_full_name)
end

#left_and_rights_valid? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 130

def left_and_rights_valid?
  ## AS clause not supported in Oracle in FROM clause for aliasing table name
  joins("LEFT OUTER JOIN #{quoted_table_name}" +
      (connection.adapter_name.match(/Oracle/).nil? ?  " AS " : " ") +
      "parent ON " +
      "#{quoted_parent_column_full_name} = parent.#{primary_key}").
  where(
      "#{quoted_left_column_full_name} IS NULL OR " +
      "#{quoted_right_column_full_name} IS NULL OR " +
      "#{quoted_left_column_full_name} >= " +
        "#{quoted_right_column_full_name} OR " +
      "(#{quoted_parent_column_full_name} IS NOT NULL AND " +
        "(#{quoted_left_column_full_name} <= parent.#{quoted_left_column_name} OR " +
        "#{quoted_right_column_full_name} >= parent.#{quoted_right_column_name}))"
  ).count == 0
end

#no_duplicates_for_columns? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 147

def no_duplicates_for_columns?
  scope_string = Array(acts_as_nested_set_options[:scope]).map do |c|
    connection.quote_column_name(c)
  end.push(nil).join(", ")
  [quoted_left_column_full_name, quoted_right_column_full_name].all? do |column|
    # No duplicates
    select("#{scope_string}#{column}, COUNT(#{column})").
        group("#{scope_string}#{column}").
        having("COUNT(#{column}) > 1").
        first.nil?
  end
end

#rebuild!(validate_nodes = true) ⇒ Object

Rebuilds the left & rights if unset or invalid. Also very useful for converting from acts_as_tree.



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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 183

def rebuild!(validate_nodes = true)
  # default_scope with order may break database queries so we do all operation without scope
  unscoped do
    # Don't rebuild a valid tree.
    return true if valid?

    scope = lambda{|node|}
    if acts_as_nested_set_options[:scope]
      scope = lambda{|node|
        scope_column_names.inject(""){|str, column_name|
          str << "AND #{connection.quote_column_name(column_name)} = #{connection.quote(node.send(column_name.to_sym))} "
        }
      }
    end
    indices = {}

    set_left_and_rights = lambda do |node|
      # set left
      node[left_column_name] = indices[scope.call(node)] += 1
      # find
      where(["#{quoted_parent_column_full_name} = ? #{scope.call(node)}", node]).order("#{quoted_left_column_full_name}, #{quoted_right_column_full_name}, id").each{|n| set_left_and_rights.call(n) }
      # set right
      node[right_column_name] = indices[scope.call(node)] += 1
      node.save!(:validate => validate_nodes)
    end

    # Find root node(s)
    root_nodes = where("#{quoted_parent_column_full_name} IS NULL").order("#{quoted_left_column_full_name}, #{quoted_right_column_full_name}, id").each do |root_node|
      # setup index for this scope
      indices[scope.call(root_node)] ||= 0
      set_left_and_rights.call(root_node)
    end
  end
end

#root ⇒ Object

Returns the first root



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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 114

def root
  roots.first
end

#roots ⇒ Object 



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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 118

def roots
  where(parent_column_name => nil).order(quoted_left_column_full_name)
end

#sorted_each_with_level(objects, order) ⇒ Object

Same as each_with_level - Accepts a string as a second argument to sort the list Example:

Category.each_with_level(Category.root.self_and_descendants, :sort_by_this_column) do |o, level|



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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 245

def sorted_each_with_level(objects, order)
  path = [nil]
  children = []
    objects.each do |o|
    children << o if o.leaf?
    if o.parent_id != path.last
      if !children.empty? && !o.leaf?
        children.sort_by! &order
        children.each { |c| yield(c, path.length-1) }
        children = []
      end
      # we are on a new level, did we decent or ascent?
      if path.include?(o.parent_id)
        # remove wrong wrong tailing paths elements
        path.pop while path.last != o.parent_id
      else
        path << o.parent_id
      end
    end
    yield(o,path.length-1) if !o.leaf?
  end
  if !children.empty?
    children.sort_by! &order
    children.each { |c| yield(c, path.length-1) }
  end
end

#valid? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 126

def valid?
  left_and_rights_valid? && no_duplicates_for_columns? && all_roots_valid?
end