module Ancestry::ClassMethods

Constants

ANCESTRY_UNCAST_TYPES

Public Instance Methods

arrange(options = {}) click to toggle source

Get all nodes and sort them into an empty hash

# File lib/ancestry/class_methods.rb, line 41
def arrange options = {}
  if (order = options.delete(:order))
    arrange_nodes self.ancestry_base_class.order(order).where(options)
  else
    arrange_nodes self.ancestry_base_class.where(options)
  end
end
arrange_nodes(nodes) click to toggle source

arranges array of nodes to a hierarchical hash

@param nodes [Array] nodes to be arranged @returns Hash{Node => {Node => {}, Node => {}}} If a node's parent is not included, the node will be included as if it is a top level node

# File lib/ancestry/class_methods.rb, line 54
def arrange_nodes(nodes)
  node_ids = Set.new(nodes.map(&:id))
  index = Hash.new { |h, k| h[k] = {} }

  nodes.each_with_object({}) do |node, arranged|
    children = index[node.id]
    index[node.parent_id][node] = children
    arranged[node] = children unless node_ids.include?(node.parent_id)
  end
end
arrange_serializable(options={}) { |parent, arrange_serializable(options, children, &block)| ... } click to toggle source

Arrangement to nested array for serialization You can also supply your own serialization logic using blocks also allows you to pass the order just as you can pass it to the arrange method

# File lib/ancestry/class_methods.rb, line 80
def arrange_serializable options={}, nodes=nil, &block
  nodes = arrange(options) if nodes.nil?
  nodes.map do |parent, children|
    if block_given?
      yield parent, arrange_serializable(options, children, &block)
    else
      parent.serializable_hash.merge 'children' => arrange_serializable(options, children)
    end
  end
end
build_ancestry_from_parent_ids!(column=:parent_id, parent_id = nil, ancestor_ids = []) click to toggle source

Build ancestry from parent ids for migration purposes

# File lib/ancestry/class_methods.rb, line 215
def build_ancestry_from_parent_ids! column=:parent_id, parent_id = nil, ancestor_ids = []
  unscoped_where do |scope|
    scope.where(column => parent_id).find_each do |node|
      node.without_ancestry_callbacks do
        node.update_attribute :ancestor_ids, ancestor_ids
      end
      build_ancestry_from_parent_ids! column, node.id, ancestor_ids + [node.id]
    end
  end
end
check_ancestry_integrity!(options = {}) click to toggle source

Integrity checking compromised tree integrity is unlikely without explicitly setting cyclic parents or invalid ancestry and circumventing validation just in case, raise an AncestryIntegrityException if issues are detected specify :report => :list to return an array of exceptions or :report => :echo to echo any error messages

# File lib/ancestry/class_methods.rb, line 127
def check_ancestry_integrity! options = {}
  parents = {}
  exceptions = [] if options[:report] == :list

  unscoped_where do |scope|
    # For each node ...
    scope.find_each do |node|
      begin
        # ... check validity of ancestry column
        if !node.sane_ancestor_ids?
          raise Ancestry::AncestryIntegrityException.new(I18n.t("ancestry.invalid_ancestry_column",
                                                                :node_id => node.id,
                                                                :ancestry_column => "#{node.read_attribute node.ancestry_column}"
                                                                ))
        end
        # ... check that all ancestors exist
        node.ancestor_ids.each do |ancestor_id|
          unless exists? ancestor_id
            raise Ancestry::AncestryIntegrityException.new(I18n.t("ancestry.reference_nonexistent_node",
                                                                  :node_id => node.id,
                                                                  :ancestor_id => ancestor_id
                                                                  ))
          end
        end
        # ... check that all node parents are consistent with values observed earlier
        node.path_ids.zip([nil] + node.path_ids).each do |node_id, parent_id|
          parents[node_id] = parent_id unless parents.has_key? node_id
          unless parents[node_id] == parent_id
            raise Ancestry::AncestryIntegrityException.new(I18n.t("ancestry.conflicting_parent_id",
                                                                  :node_id => node_id,
                                                                  :parent_id => parent_id || 'nil',
                                                                  :expected => parents[node_id] || 'nil'
                                                                  ))
          end
        end
      rescue Ancestry::AncestryIntegrityException => integrity_exception
        case options[:report]
          when :list then exceptions << integrity_exception
          when :echo then puts integrity_exception
          else raise integrity_exception
        end
      end
    end
  end
  exceptions if options[:report] == :list
end
flatten_arranged_nodes(arranged, nodes = []) click to toggle source

convert a hash of the form {node => children} to an array of nodes, child first

@param arranged [Hash{Node => {Node => {}, Node => {}}}] arranged nodes @returns [Array] array of nodes with the parent before the children

# File lib/ancestry/class_methods.rb, line 69
def flatten_arranged_nodes(arranged, nodes = [])
  arranged.each do |node, children|
    nodes << node
    flatten_arranged_nodes(children, nodes) unless children.empty?
  end
  nodes
end
orphan_strategy=(orphan_strategy) click to toggle source

Orphan strategy writer

# File lib/ancestry/class_methods.rb, line 25
def orphan_strategy= orphan_strategy
  # Check value of orphan strategy, only rootify, adopt, restrict or destroy is allowed
  if [:rootify, :adopt, :restrict, :destroy].include? orphan_strategy
    class_variable_set :@@orphan_strategy, orphan_strategy
  else
    raise Ancestry::AncestryException.new(I18n.t("ancestry.invalid_orphan_strategy"))
  end
end
primary_key_is_an_integer?() click to toggle source
# File lib/ancestry/class_methods.rb, line 244
def primary_key_is_an_integer?
  if defined?(@primary_key_is_an_integer)
    @primary_key_is_an_integer
  else
    @primary_key_is_an_integer = !ANCESTRY_UNCAST_TYPES.include?(type_for_attribute(primary_key).type)
  end
end
rebuild_depth_cache!() click to toggle source

Rebuild depth cache if it got corrupted or if depth caching was just turned on

# File lib/ancestry/class_methods.rb, line 227
def rebuild_depth_cache!
  raise Ancestry::AncestryException.new(I18n.t("ancestry.cannot_rebuild_depth_cache")) unless respond_to? :depth_cache_column

  self.ancestry_base_class.transaction do
    unscoped_where do |scope|
      scope.find_each do |node|
        node.update_attribute depth_cache_column, node.depth
      end
    end
  end
end
restore_ancestry_integrity!() click to toggle source

Integrity restoration

# File lib/ancestry/class_methods.rb, line 175
def restore_ancestry_integrity!
  parent_ids = {}
  # Wrap the whole thing in a transaction ...
  self.ancestry_base_class.transaction do
    unscoped_where do |scope|
      # For each node ...
      scope.find_each do |node|
        # ... set its ancestry to nil if invalid
        if !node.sane_ancestor_ids?
          node.without_ancestry_callbacks do
            node.update_attribute :ancestor_ids, []
          end
        end
        # ... save parent id of this node in parent_ids array if it exists
        parent_ids[node.id] = node.parent_id if exists? node.parent_id

        # Reset parent id in array to nil if it introduces a cycle
        parent_id = parent_ids[node.id]
        until parent_id.nil? || parent_id == node.id
          parent_id = parent_ids[parent_id]
        end
        parent_ids[node.id] = nil if parent_id == node.id
      end

      # For each node ...
      scope.find_each do |node|
        # ... rebuild ancestry from parent_ids array
        ancestor_ids, parent_id = [], parent_ids[node.id]
        until parent_id.nil?
          ancestor_ids, parent_id = [parent_id] + ancestor_ids, parent_ids[parent_id]
        end
        node.without_ancestry_callbacks do
          node.update_attribute :ancestor_ids, ancestor_ids
        end
      end
    end
  end
end
scope_depth(depth_options, depth) click to toggle source

Scope on relative depth options

# File lib/ancestry/class_methods.rb, line 13
def scope_depth depth_options, depth
  depth_options.inject(self.ancestry_base_class) do |scope, option|
    scope_name, relative_depth = option
    if [:before_depth, :to_depth, :at_depth, :from_depth, :after_depth].include? scope_name
      scope.send scope_name, depth + relative_depth
    else
      raise Ancestry::AncestryException.new(I18n.t("ancestry.unknown_depth_option", scope_name: scope_name))
    end
  end
end
sort_by_ancestry(nodes) { |a, b| ... } click to toggle source

Pseudo-preordered array of nodes. Children will always follow parents, This is deterministic unless the parents are missing and a sort block is specified

# File lib/ancestry/class_methods.rb, line 107
def sort_by_ancestry(nodes, &block)
  arranged = nodes if nodes.is_a?(Hash)

  unless arranged
    presorted_nodes = nodes.sort do |a, b|
      rank = (a.public_send(ancestry_column) || ' ') <=> (b.public_send(ancestry_column) || ' ')
      rank = yield(a, b) if rank == 0 && block_given?
      rank
    end

    arranged = arrange_nodes(presorted_nodes)
  end

  flatten_arranged_nodes(arranged)
end
to_node(object) click to toggle source

Fetch tree node if necessary

# File lib/ancestry/class_methods.rb, line 4
def to_node object
  if object.is_a?(self.ancestry_base_class)
    object
  else
    unscoped_where { |scope| scope.find(object.try(primary_key) || object) }
  end
end
tree_view(column, data = nil) click to toggle source
# File lib/ancestry/class_methods.rb, line 91
def tree_view(column, data = nil)
  data = arrange unless data
  data.each do |parent, children|
    if parent.depth == 0
      puts parent[column]
    else
      num = parent.depth - 1
      indent = "   "*num
      puts " #{"|" if parent.depth > 1}#{indent}|_ #{parent[column]}"
    end
    tree_view(column, children) if children
  end
end
unscoped_where() { |ancestry_base_class.unscope(:where)| ... } click to toggle source
# File lib/ancestry/class_methods.rb, line 239
def unscoped_where
  yield self.ancestry_base_class.default_scoped.unscope(:where)
end