module Mongoid::CategorizedCounterCache::ClassMethods

Public Instance Methods

categorized_counter_cache(relation_name) { |self| ... } click to toggle source
# File lib/mongoid/categorized_counter_cache.rb, line 12
def categorized_counter_cache relation_name
  relation = self.relations[relation_name.to_s]
  cache_column_base = relation.inverse_class_name.demodulize.underscore.pluralize

  after_create do
    category = yield self
    cache_column = "#{cache_column_base}_#{category}_count"

    if record = __send__(relation_name)
      record[cache_column] = (record[cache_column] || 0) + 1

      if record.persisted?
        record.class.with(record.persistence_context) do |_class|
          _class.increment_counter(cache_column, record._id)
        end
        record.remove_change(cache_column)
      end
    end
  end

  after_update do
    foreign_key = relation.foreign_key
    category = yield self
    cache_column = "#{cache_column_base}_#{category}_count"

    if record = __send__(relation_name)
      if attribute_changed?(foreign_key)
        original, current = attribute_change(foreign_key)

        unless original.nil?
          record.class.with(persistence_context) do |_class|
            _class.decrement_counter(cache_column, original)
          end
        end

        unless current.nil?
          record[cache_column] = (record[cache_column] || 0) + 1
          record.class.with(record.persistence_context) do |_class|
            _class.increment_counter(cache_column, current) if record.persisted?
          end
        end
      end
    elsif attribute_changed?(foreign_key)
      original, current = attribute_change(foreign_key)

      unless original.nil?
        relation.klass.with(persistence_context) do |_class|
          _class.decrement_counter(cache_column, original)
        end
      end
    end
  end

  before_destroy do
    if record = __send__(relation_name)
      category = yield self
      cache_column = "#{cache_column_base}_#{category}_count"
      record[cache_column] = (record[cache_column] || 0) - 1 unless record.frozen?

      if record.persisted?
        record.class.with(record.persistence_context) do |_class|
          _class.decrement_counter(cache_column, record._id)
        end
        record.remove_change(cache_column)
      end
    end
  end

end