Install dependencies

Before you begin this tutorial, ensure you have the following dependencies installed in your development environment:

• Compiler that supports C++17, such as GCC, Clang, or Visual Studio

• CMake v3.15 or later

• pkg-config

Download the C++ driver

To download the latest version of the C++ driver from the mongo-cxx-driver Github repository, run the following commands in your shell from your root directory:

curl -OL https://github.com/mongodb/mongo-cxx-driver/releases/download/r4.0.0/mongo-cxx-driver-r4.0.0.tar.gz
tar -xzf mongo-cxx-driver-r4.0.0.tar.gz
cd mongo-cxx-driver-r4.0.0/build

Configure the driver for installation

Select the tab corresponding to your operating system and run following command from your mongo-cxx-driver-r4.0.0/build directory:

cmake ..                                \
    -DCMAKE_BUILD_TYPE=Release          \
    -DCMAKE_CXX_STANDARD=17

'C:\<path>\cmake.exe' .. \
    -G "Visual Studio <version> <year>" -A "x64"         \
    -DCMAKE_CXX_STANDARD=17                     \
    -DCMAKE_INSTALL_PREFIX=C:\mongo-cxx-driver  \

Build and install the driver

Select the tab corresponding to your operating system and run following commands to install the driver:

cmake --build .
sudo cmake --build . --target install

cmake --build . --config RelWithDebInfo
cmake --build . --target install --config RelWithDebInfo

Create a Free MongoDB deployment on Atlas

Complete the Get Started with Atlas guide to set up a new Atlas account and load sample data into a new free tier MongoDB deployment.

Save your Credentials

After you create your database user, save that user's username and password to a safe location for use in an upcoming step.

Find your MongoDB Atlas Connection String

To retrieve your connection string for the deployment that you created in the previous step, log in to your Atlas account and navigate to the Database section and click the Connect button for your new deployment.

Proceed to the Connect your application section and select "C++" from the Driver selection menu and the version that best matches the version you installed from the Version selection menu.

Select the Password (SCRAM) authentication mechanism.

Deselect the Include full driver code example option to view only the connection string.

Copy your Connection String

Click the button on the right of the connection string to copy it to your clipboard, as shown in the following screenshot:

Update the Placeholders

Paste this connection string into a file in your preferred text editor and replace the <username> and <password> placeholders with your database user's username and password.

Save this file to a safe location for use in the next step.

Create a project directory

From your root directory, run the following command in your shell to create a directory called cpp-quickstart for this project:

mkdir cpp-quickstart

Run the following commands to create a quickstart.cpp application file in the cpp-quickstart directory:

cd cpp-quickstart
touch quickstart.cpp

Create your C++ driver application

Copy and paste the following code into the quickstart.cpp file, which queries the movies collection in the sample_mflix database:

#include <cstdint>
#include <iostream>
#include <vector>
#include <bsoncxx/builder/basic/document.hpp>
#include <bsoncxx/json.hpp>
#include <mongocxx/client.hpp>
#include <mongocxx/instance.hpp>
#include <mongocxx/uri.hpp>
using bsoncxx::builder::basic::kvp;
using bsoncxx::builder::basic::make_document;
int main() {
    mongocxx::instance instance;
    mongocxx::uri uri("<connection string>");
    mongocxx::client client(uri);
    auto db = client["sample_mflix"];
    auto collection = db["movies"];
    auto result = collection.find_one(make_document(kvp("title", "The Shawshank Redemption")));
    std::cout << bsoncxx::to_json(*result) << std::endl;
}

Assign the connection string

Replace the <connection string> placeholder with the connection string that you copied from the Create a Connection String step of this guide.

Run your C++ application

In your shell, run the following commands to compile and run this application:

c++ --std=c++17 quickstart.cpp $(pkg-config --cflags --libs libmongocxx) -o ./app.out
./app.out

dyld[54430]: Library not loaded: @rpath/libmongocxx._noabi.dylib

c++ --std=c++17 quickstart.cpp -Wl,-rpath,/usr/local/lib/ $(pkg-config --cflags --libs libmongocxx) -o ./app.out
./app.out

The command line output contains details about the retrieved movie document:

{ "_id" : { "$oid" : "573a1399f29313caabceeb20" },
"plot" : "Two imprisoned men bond over a number of years, finding solace
and eventual redemption through acts of common decency.",
...
"title" : "The Shawshank Redemption",
...

If you encounter an error or see no output, ensure that you specified the proper connection string in the quickstart.cpp file and that you loaded the sample data.