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// Copyright 2009-present 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.
#include <bsoncxx/builder/basic/array.hpp>
#include <bsoncxx/builder/basic/document.hpp>
#include <bsoncxx/builder/basic/kvp.hpp>
#include <mongocxx/client.hpp>
#include <mongocxx/instance.hpp>
#include <mongocxx/uri.hpp>
#include <examples/macros.hh>
using bsoncxx::builder::basic::array;
using bsoncxx::builder::basic::kvp;
using bsoncxx::builder::basic::make_document;
int EXAMPLES_CDECL main() {
// The mongocxx::instance constructor and destructor initialize and shut down the driver,
// respectively. Therefore, a mongocxx::instance must be created before using the driver and
// must remain alive for as long as the driver is in use.
mongocxx::instance inst{};
mongocxx::client conn{mongocxx::uri{}};
auto db = conn["test"];
// Many driver methods take a bsoncxx::document::view_or_value as
// a parameter. You can use these methods with either a document::view
// or a document::value.
// Document::views can be passed in directly:
{
bsoncxx::document::value command = make_document(kvp("ping", 1));
bsoncxx::document::view command_view = command.view();
auto res = db.run_command(command_view);
}
// Document::values can be passed in one of two ways:
// 1. Pass a view of the document::value
{
bsoncxx::document::value command = make_document(kvp("ping", 1));
auto res = db.run_command(command.view());
}
// 2. Pass ownership of the document::value into the method
{
bsoncxx::document::value command = make_document(kvp("ping", 1));
auto res = db.run_command(std::move(command));
}
// Temporary document::values are captured and owned by the view_or_value type
{
auto res = db.run_command(make_document(kvp("ping", 1)));
// NOTE: there is no need to call .view() on a temporary document::value in
// a call like this, and doing so could result in a use-after-free error.
// BAD:
// auto res = db.run_command(make_document(kvp("ping", 1)).view());
}
}
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