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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 <iostream>
#include <list>
#include <numeric>
#include <sstream>
#include <vector>
#include <bsoncxx/builder/basic/array.hpp>
#include <bsoncxx/builder/basic/document.hpp>
#include <bsoncxx/string/to_string.hpp>
#include <mongocxx/client.hpp>
#include <mongocxx/exception/exception.hpp>
#include <mongocxx/exception/logic_error.hpp>
#include <mongocxx/instance.hpp>
#include <examples/macros.hh>
using namespace mongocxx;
namespace {
void aggregation_examples(const mongocxx::database& db) {
{
// Start Aggregation Example 1
using namespace bsoncxx::builder::basic;
mongocxx::pipeline p{};
p.match(make_document(kvp("items.fruit", "banana")));
p.sort(make_document(kvp("date", 1)));
auto cursor = db["sales"].aggregate(p, mongocxx::options::aggregate{});
// End Aggregation Example 1
auto count = std::distance(cursor.begin(), cursor.end());
if (count != 0L) {
throw std::logic_error("wrong count in example 1");
}
}
{
// Start Aggregation Example 2
using namespace bsoncxx::builder::basic;
mongocxx::pipeline p{};
p.unwind("$items");
p.match(make_document(kvp("items.fruit", "banana")));
p.group(make_document(
kvp("_id", make_document(kvp("day", make_document(kvp("$dayOfWeek", "$date"))))),
kvp("count", make_document(kvp("$sum", "$items.quantity")))));
p.project(make_document(
kvp("dayOfWeek", "$_id.day"), kvp("numberSold", "$count"), kvp("_id", 0)));
p.sort(make_document(kvp("numberSold", 1)));
auto cursor = db["sales"].aggregate(p, mongocxx::options::aggregate{});
// End Aggregation Example 2
auto count = std::distance(cursor.begin(), cursor.end());
if (count != 0L) {
throw std::logic_error("wrong count in example 2");
}
}
{
// Start Aggregation Example 3
using namespace bsoncxx::builder::basic;
mongocxx::pipeline p{};
p.unwind("$items");
p.group(make_document(
kvp("_id", make_document(kvp("day", make_document(kvp("$dayOfWeek", "$date"))))),
kvp("items_sold", make_document(kvp("$sum", "$items.quantity"))),
kvp("revenue",
make_document(
kvp("$sum",
make_document(
kvp("$multiply", make_array("$items.quantity", "$items.price"))))))));
p.project(make_document(
kvp("day", "$_id.day"),
kvp("revenue", 1),
kvp("items_sold", 1),
kvp("discount",
make_document(
kvp("$cond",
make_document(
kvp("if", make_document(kvp("$lte", make_array("$revenue", 250)))),
kvp("then", 25),
kvp("else", 0)))))));
auto cursor = db["sales"].aggregate(p, mongocxx::options::aggregate{});
// End Aggregation Example 3
auto count = std::distance(cursor.begin(), cursor.end());
if (count != 0L) {
throw std::logic_error("wrong count in example 3");
}
}
{
// Start Aggregation Example 4
using namespace bsoncxx::builder::basic;
mongocxx::pipeline p{};
p.lookup(make_document(
kvp("from", "air_airlines"),
kvp("let", make_document(kvp("constituents", "$airlines"))),
kvp("pipeline",
make_array(make_document(
kvp("$match",
make_document(kvp(
"$expr",
make_document(kvp("$in", make_array("$name", "$$constituents"))))))))),
kvp("as", "airlines")));
p.project(make_document(
kvp("_id", 0),
kvp("name", 1),
kvp("airlines",
make_document(kvp(
"$filter",
make_document(kvp("input", "$airlines"),
kvp("as", "airline"),
kvp("cond",
make_document(kvp(
"$eq", make_array("$$airline.country", "Canada"))))))))));
auto cursor = db["air_alliances"].aggregate(p, mongocxx::options::aggregate{});
// End Aggregation Example 4
auto count = std::distance(cursor.begin(), cursor.end());
if (count != 0L) {
throw std::logic_error("wrong count in example 4");
}
}
}
} // namespace
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.
const mongocxx::instance inst{};
const mongocxx::client conn{mongocxx::uri{}};
auto const db = conn["documentation_examples"];
// SERVER-79306: Ensure the database exists for consistent behavior with sharded clusters.
conn["documentation_examples"].create_collection("dummy");
try {
aggregation_examples(db);
} catch (const std::logic_error& e) {
std::cerr << e.what() << std::endl;
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}
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