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 155

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

#each_root_valid?(roots_to_validate) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 165

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 217

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 116

def leaves
  where("#{quoted_right_column_name} - #{quoted_left_column_name} = 1").order(quoted_left_column_name)
end

#left_and_rights_valid? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 124

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_table_name}.#{quoted_parent_column_name} = parent.#{primary_key}").
  where(
      "#{quoted_table_name}.#{quoted_left_column_name} IS NULL OR " +
      "#{quoted_table_name}.#{quoted_right_column_name} IS NULL OR " +
      "#{quoted_table_name}.#{quoted_left_column_name} >= " +
        "#{quoted_table_name}.#{quoted_right_column_name} OR " +
      "(#{quoted_table_name}.#{quoted_parent_column_name} IS NOT NULL AND " +
        "(#{quoted_table_name}.#{quoted_left_column_name} <= parent.#{quoted_left_column_name} OR " +
        "#{quoted_table_name}.#{quoted_right_column_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 141

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_name, quoted_right_column_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 177

def rebuild!(validate_nodes = true)
  # 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_name} = ? #{scope.call(node)}", node]).order("#{quoted_left_column_name}, #{quoted_right_column_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_name} IS NULL").order("#{quoted_left_column_name}, #{quoted_right_column_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

#root ⇒ Object

Returns the first root



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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 108

def root
  roots.first
end

#roots ⇒ Object 



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# File 'lib/awesome_nested_set/awesome_nested_set.rb', line 112

def roots
  where(parent_column_name => nil).order(quoted_left_column_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 236

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 120

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