Contents

module MemoryModel
  class Collection
    class Index
      class Multi < MemoryModel::Collection::Index

        # `create` should implement creating a new record, raising an error if an item with the matching storage id already
        # exists in the index.
        def create(key, item)
          insert_into_key(key, item)
        end

        # `update` should find a record in the collection by its storage_id, remove it, and add with the new value.
        def update(key, item)
          raise(RecordNotInIndexError, [self, item]) unless exists? item
          delete(item)
          create(key, item)
        end

        # `read` should find a record in the collection by its indexed_value, remove it, and add with the new value.
        def read(key)
          index[key].first
        end

        # `delete` should find a record in the collection by its indexed_value, and remove it.
        def delete(key)
          index.values.map { |refs| refs.delete key }
        end

        # `exists?` return whether or not an item with the given storage id exists.
        def exists?(item)
          index.values.any? { |refs| refs.has_key? item.uuid }
        end

        # `values` should return the values of the index
        def values
          index.values.map(&:values)
        end

        private

        def where_using_default(matcher)
          Array.wrap index[matcher].try(:values)
        end

        def where_using_proc(matcher)
          index.slice(*index.keys.select(&matcher)).values.map(&:values).flatten
        end

        def where_using_regexp(matcher)
          where_using_proc ->(key) { key =~ matcher }
        end

        def insert_into_key(key, item)
          index[key]            ||= {}
          index[key][item.uuid] = item
        end

      end
    end
  end
end

Version data entries

2 entries across 2 versions & 1 rubygems

Version	Path
memory_model-1.0.0	lib/memory_model/collection/index/multi.rb
memory_model-0.1.0	lib/memory_model/collection/index/multi.rb