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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 <cstdlib>
#include <bsoncxx/builder/stream/array.hpp>
#include <bsoncxx/builder/stream/document.hpp>
#include <bsoncxx/builder/stream/helpers.hpp>
#include <bsoncxx/types.hpp>
#include <bsoncxx/config/prelude.hpp>
#include <examples/macros.hh>
using namespace bsoncxx;
int EXAMPLES_CDECL main() {
using namespace builder::stream;
builder::stream::document build_doc;
// {
// "_id" : 1,
// "name" : { "first" : "John", "last" : "Backus" },
// "contribs" : [ "Fortran", "ALGOL", "Backus-Naur Form", "FP" ],
// "awards" : [
// {
// "award" : "W.W. McDowell Award",
// "year" : 1967,
// "by" : "IEEE Computer Society"
// },
// { "award" : "Draper Prize",
// "year" : 1993,
// "by" : "National Academy of Engineering"
// }
// ]
// }
build_doc << "_id" << 1 << "name" << open_document << "first"
<< "John"
<< "last"
<< "Backus" << close_document << "contribs" << open_array << "Fortran"
<< "ALGOL"
<< "Backus-Naur Form"
<< "FP" << close_array << "awards" << open_array << open_document << "award"
<< "W.W. McDowell Award"
<< "year" << 1967 << "by"
<< "IEEE Computer Society" << close_document << open_document << "award"
<< "Draper Prize"
<< "year" << 1993 << "by"
<< "National Academy of Engineering" << close_document << close_array;
auto doc = build_doc.view();
// Once we have the document view, we can use ["key"] or [index] notation to reach into nested
// documents or arrays.
auto awards = doc["awards"];
auto first_award_year = awards[0]["year"];
auto second_award_year = doc["awards"][1]["year"];
auto last_name = doc["name"]["last"];
// If the key doesn't exist, or index is out of bounds, we get invalid elements.
auto invalid1 = doc["name"]["middle"];
auto invalid2 = doc["contribs"][1000];
if (invalid1 || invalid2) {
BSONCXX_UNREACHABLE; // Not reached.
}
// Similarly, indexed access (either by string or numeric index) into a type that is not
// a document or an array yields invalid eleemnts.
auto invalid3 = doc["_id"]["invalid"];
auto invalid4 = doc["name"][3];
if (invalid3 || invalid4) {
BSONCXX_UNREACHABLE; // Not reached.
}
// Values are accessed through get_*() methods.
auto id_i32 = doc["_id"].get_int32().value;
auto first_name_str = doc["name"]["first"].get_string().value;
// Make all variables used.
return (awards && first_award_year && second_award_year && last_name && id_i32 == 1 &&
first_name_str == "John")
? EXIT_SUCCESS
: EXIT_FAILURE;
}
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