Class: LargeTree

Inherits:

Object

• Object
• LargeTree

Includes:

JSONModel

Defined in:

backend/app/model/large_tree.rb

Constant Summary

WAYPOINT_SIZE =

200

Constants included from JSONModel

JSONModel::REFERENCE_KEY_REGEX

Instance Method Summary

• #add_decorator(decorator) ⇒ Object
• #initialize(root_record, opts = {}) ⇒ LargeTree constructor

  A new instance of LargeTree.

• #node(node_record) ⇒ Object
• #node_from_root(node_ids, repo_id) ⇒ Object
• #published_filter ⇒ Object
• #root ⇒ Object
• #waypoint(parent_id, offset) ⇒ Object

Methods included from JSONModel

JSONModel, #JSONModel, add_error_handler, all, allow_unmapped_enum_value, backend_url, check_valid_refs, client_mode?, custom_validations, destroy_model, enum_default_value, enum_values, handle_error, init, load_schema, #models, models, parse_jsonmodel_ref, parse_reference, repository, repository_for, schema_src, set_publish_flags!, set_repository, strict_mode, strict_mode?, validate_schema, with_repository

Constructor Details

#initialize(root_record, opts = {}) ⇒ LargeTree

Returns a new instance of LargeTree.

# File 'backend/app/model/large_tree.rb', line 59

def initialize(root_record, opts = {})
  @decorators = []

  @root_record = root_record

  @root_table = @root_type = root_record.class.root_type.intern
  @node_table = @node_type = root_record.class.node_type.intern

  @published_only = opts.fetch(:published_only, false)
end

Instance Method Details

#add_decorator(decorator) ⇒ Object

# File 'backend/app/model/large_tree.rb', line 70

def add_decorator(decorator)
  @decorators << decorator
end

#node(node_record) ⇒ Object

# File 'backend/app/model/large_tree.rb', line 108

def node(node_record)
  DB.open do |db|
    child_count = db[@node_table]
                  .filter(:root_record_id => @root_record.id,
                          :parent_id => node_record.id)
                  .filter(published_filter)
                  .count

    my_position = node_record.position

    node_position = db[@node_table]
                    .filter(:root_record_id => @root_record.id,
                            :parent_id => node_record.parent_id)
                    .filter(published_filter)
                    .where { position < my_position }
                    .count + 1

    response = waypoint_response(child_count).merge("title" => node_record.display_string,
                                                    "uri" => node_record.uri,
                                                    "position" => node_position,
                                                    "jsonmodel_type" => @node_table.to_s)

    @decorators.each do |decorator|
      response = decorator.node(response, node_record)
    end

    precalculate_waypoints(response, node_record.id)

    response
  end
end

#node_from_root(node_ids, repo_id) ⇒ Object

# File 'backend/app/model/large_tree.rb', line 140

def node_from_root(node_ids, repo_id)
  child_to_parent_map = {}
  node_to_position_map = {}
  node_to_root_record_map = {}
  node_to_title_map = {}

  result = {}

  DB.open do |db|
    ## Fetch our mappings of nodes to parents and nodes to positions
    nodes_to_expand = node_ids

    while !nodes_to_expand.empty?
      # Get the set of parents of the current level of nodes
      next_nodes_to_expand = []

      db[@node_table]
        .filter(:id => nodes_to_expand)
        .filter(published_filter)
        .select(:id, :parent_id, :root_record_id, :position, :display_string).each do |row|
        child_to_parent_map[row[:id]] = row[:parent_id]
        node_to_position_map[row[:id]] = row[:position]
        node_to_title_map[row[:id]] = row[:display_string]
        node_to_root_record_map[row[:id]] = row[:root_record_id]
        next_nodes_to_expand << row[:parent_id]
      end

      nodes_to_expand = next_nodes_to_expand.compact.uniq
    end

    ## Calculate the waypoint that each node will fall into
    node_to_waypoint_map = {}

    (child_to_parent_map.keys + child_to_parent_map.values).compact.uniq.each do |node_id|
      this_position = db[@node_type]
                      .filter(:parent_id => child_to_parent_map[node_id])
                      .filter(:root_record_id => node_to_root_record_map[node_id])
                      .filter(published_filter)
                      .where { position <= node_to_position_map[node_id] }
                      .count

      node_to_waypoint_map[node_id] = (this_position / WAYPOINT_SIZE)
    end

    root_record_titles = {}
    db[@root_table]
      .join(@node_table, :root_record_id => :id)
      .filter(Sequel.qualify(@node_table, :id) => node_ids)
      .select(Sequel.qualify(@root_table, :id),
              Sequel.qualify(@root_table, :title))
      .distinct
      .each do |row|
      root_record_titles[row[:id]] = row[:title]
    end

    ## Build up the path of waypoints for each node
    node_ids.each do |node_id|
      root_record_id = node_to_root_record_map.fetch(node_id)
      root_record_uri = JSONModel(@root_type).uri_for(root_record_id, :repo_id => repo_id)

      path = []

      current_node = node_id
      while child_to_parent_map[current_node]
        parent_node = child_to_parent_map[current_node]

        path << {"node" => JSONModel(@node_type).uri_for(parent_node, :repo_id => repo_id),
                 "root_record_uri" => root_record_uri,
                 "jsonmodel_type" => @node_type,
                 "title" => node_to_title_map.fetch(parent_node),
                 "offset" => node_to_waypoint_map.fetch(current_node),
                 "parsed_title" => MixedContentParser.parse(node_to_title_map.fetch(parent_node), '/')}

        current_node = parent_node
      end

      path << {"node" => nil,
               "root_record_uri" => root_record_uri,
               "offset" => node_to_waypoint_map.fetch(current_node),
               "jsonmodel_type" => @root_type,
               "title" => root_record_titles[root_record_id],
               "parsed_title" => MixedContentParser.parse(root_record_titles[root_record_id], '/')}

      result[node_id] = path.reverse
    end
  end

  result
end

#published_filter ⇒ Object

# File 'backend/app/model/large_tree.rb', line 74

def published_filter
  filter = {}

  filter[:publish] = @published_only ? [1] : [0, 1]
  filter[:suppressed] = @published_only ? [0] : [0, 1]

  filter
end

#root ⇒ Object

# File 'backend/app/model/large_tree.rb', line 83

def root
  DB.open do |db|
    child_count = db[@node_table]
                  .filter(:root_record_id => @root_record.id,
                          :parent_id => nil)
                  .filter(published_filter)
                  .count


    # ANW-617: generate a slugged URL for inclusion in the JSON for the root node that's being returned to the LargeTree JS so it can be used in place of the URIs if needed.
    response = waypoint_response(child_count).merge("title" => @root_record.title,
                                                    "uri" => @root_record.uri,
                                                    "slugged_url" => SlugHelpers.get_slugged_url_for_largetree(@root_record.class.to_s, @root_record.repo_id, @root_record.slug),
                                                    "jsonmodel_type" => @root_table.to_s,
                                                    "parsed_title" => MixedContentParser.parse(@root_record.title, '/'))
    @decorators.each do |decorator|
      response = decorator.root(response, @root_record)
    end

    precalculate_waypoints(response, nil)

    response
  end
end

#waypoint(parent_id, offset) ⇒ Object

# File 'backend/app/model/large_tree.rb', line 231

def waypoint(parent_id, offset)
  record_ids = []
  records = {}

  DB.open do |db|

    # ANW-617: We need to grab the slug field from the database so we can use it to generate a slugged URL later.
    db[@node_table]
      .filter(:root_record_id => @root_record.id,
              :parent_id => parent_id)
      .filter(published_filter)
      .order(:position)
      .select(:id, :repo_id, :title, :position, :slug)
      .offset(offset * WAYPOINT_SIZE)
      .limit(WAYPOINT_SIZE)
      .each do |row|
        record_ids << row[:id]
        records[row[:id]] = row
      end

    # Count up their children
    child_counts = Hash[db[@node_table]
                         .filter(:root_record_id => @root_record.id,
                                 :parent_id => records.keys)
                         .filter(published_filter)
                         .group_and_count(:parent_id)
                         .map {|row| [row[:parent_id], row[:count]]}]

    response = record_ids.each_with_index.map do |id, idx|
      row = records[id]
      child_count = child_counts.fetch(id, 0)

      # ANW-617: generate a slugged URL for inclusion in the JSON for the standard node that's being returned to the LargeTree JS so it can be used in place of the URIs if needed.
      waypoint_response(child_count).merge("title" => row[:title],
                                           "slugged_url" => SlugHelpers.get_slugged_url_for_largetree(@node_type.to_s, row[:repo_id], row[:slug]),
                                           "parsed_title" => MixedContentParser.parse(row[:title], '/'),
                                           "uri" => JSONModel(@node_type).uri_for(row[:id], :repo_id => row[:repo_id]),
                                           "position" => (offset * WAYPOINT_SIZE) + idx,
                                           "parent_id" => parent_id,
                                           "jsonmodel_type" => @node_type.to_s)

    end

    @decorators.each do |decorator|
      response = decorator.waypoint(response, record_ids)
    end

    response
  end
end