1 2 /** 3 * Copyright (C) 2018-present MongoDB, Inc. 4 * 5 * This program is free software: you can redistribute it and/or modify 6 * it under the terms of the Server Side Public License, version 1, 7 * as published by MongoDB, Inc. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * Server Side Public License for more details. 13 * 14 * You should have received a copy of the Server Side Public License 15 * along with this program. If not, see 16 * <http://www.mongodb.com/licensing/server-side-public-license>. 17 * 18 * As a special exception, the copyright holders give permission to link the 19 * code of portions of this program with the OpenSSL library under certain 20 * conditions as described in each individual source file and distribute 21 * linked combinations including the program with the OpenSSL library. You 22 * must comply with the Server Side Public License in all respects for 23 * all of the code used other than as permitted herein. If you modify file(s) 24 * with this exception, you may extend this exception to your version of the 25 * file(s), but you are not obligated to do so. If you do not wish to do so, 26 * delete this exception statement from your version. If you delete this 27 * exception statement from all source files in the program, then also delete 28 * it in the license file. 29 */ 30 31 #pragma once 32 33 #include "mongo/db/s/balancer/balancer_random.h" 34 #include "mongo/db/s/balancer/cluster_statistics.h" 35 36 namespace mongo { 37 38 /** 39 * Default implementation for the cluster statistics gathering utility. Uses a blocking method to 40 * fetch the statistics and does not perform any caching. If any of the shards fails to report 41 * statistics fails the entire refresh. 42 */ 43 class ClusterStatisticsImpl final : public ClusterStatistics { 44 public: 45 ClusterStatisticsImpl(BalancerRandomSource& random); 46 ~ClusterStatisticsImpl(); 47 48 StatusWith<std::vector<ShardStatistics>> getStats(OperationContext* opCtx) override; 49 50 private: 51 // Source of randomness when metadata needs to be randomized. 52 BalancerRandomSource& _random; 53 }; 54 55 } // namespace mongo 56