lib/mongo/operation/map_reduce/result.rb
# frozen_string_literal: true
# rubocop:todo all
# Copyright (C) 2014-2020 MongoDB Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
module Mongo
module Operation
class MapReduce
# Defines custom behavior of results for a map reduce operation.
#
# @since 2.0.0
# @api semiprivate
class Result < Operation::Result
# The counts field for the map/reduce.
#
# @since 2.0.0
# @api private
COUNTS = 'counts'.freeze
# The field name for a result without a cursor.
#
# @since 2.0.0
# @api private
RESULTS = 'results'.freeze
# The time the operation took constant.
#
# @since 2.0.0
# @api private
TIME = 'timeMillis'.freeze
# Gets the map/reduce counts from the reply.
#
# @example Get the counts.
# result.counts
#
# @return [ Hash ] A hash of the result counts.
#
# @since 2.0.0
# @api public
def counts
reply.documents[0][COUNTS]
end
# Get the documents from the map/reduce.
#
# @example Get the documents.
# result.documents
#
# @return [ Array<BSON::Document> ] The documents.
#
# @since 2.0.0
# @api public
def documents
reply.documents[0][RESULTS] || reply.documents[0][RESULT]
end
# If the result was a command then determine if it was considered a
# success.
#
# @note If the write was unacknowledged, then this will always return
# true.
#
# @example Was the command successful?
# result.successful?
#
# @return [ true, false ] If the command was successful.
#
# @since 2.0.0
# @api public
def successful?
!documents.nil?
end
# Get the execution time of the map/reduce.
#
# @example Get the execution time.
# result.time
#
# @return [ Integer ] The executing time in milliseconds.
#
# @since 2.0.0
# @api public
def time
reply.documents[0][TIME]
end
# Validate the result by checking for any errors.
#
# @note This only checks for errors with writes since authentication is
# handled at the connection level and any authentication errors would
# be raised there, before a Result is ever created.
#
# @example Validate the result.
# result.validate!
#
# @raise [ Error::OperationFailure ] If an error is in the result.
#
# @return [ Result ] The result if verification passed.
#
# @since 2.0.0
# @api private
def validate!
documents.nil? ? raise_operation_failure : self
end
# Get the cursor id.
#
# @example Get the cursor id.
# result.cursor_id
#
# @return [ Integer ] Always 0 because map reduce doesn't return a cursor.
#
# @since 2.5.0
# @api private
def cursor_id
0
end
# Get the number of documents returned by the server in this batch.
#
# Map/Reduce operation returns documents inline without using
# cursors; as such, the standard Mongo::Reply#returned_count does
# not work correctly for Map/Reduce.
#
# Note that the Map/Reduce operation is limited to max BSON document
# size (16 MB) in its inline result set.
#
# @return [ Integer ] The number of documents returned.
#
# @api public
def returned_count
reply.documents.length
end
private
def first_document
@first_document ||= reply.documents[0]
end
end
end
end
end