C++ tutorial for AWS Cloud9 - AWS Cloud9
PrerequisitesStep 1: Install g++ and required dev packages Step 2: Install CMakeStep 3: Obtain and build the SDK for C++Step 4: Create C++ and CMakeLists filesStep 5: Build and run the C++ codeStep 6: Clean up

C++ tutorial for AWS Cloud9

This tutorial enables you to run C++ code in an AWS Cloud9 development environment. The code also uses resources provided by the AWS SDK for C++, a modularized, cross-platform, open-source library you can use to connect to Amazon Web Services.

Following this tutorial and creating this sample might result in charges to your AWS account. These include possible charges for services such as Amazon EC2 and Amazon S3. For more information, see Amazon EC2 Pricing and Amazon S3 Pricing.

Prerequisites

Before you use this sample, make sure that your setup meets the following requirements:

  • You must have an existing AWS Cloud9 EC2 development environment. This sample assumes that you already have an EC2 environment that's connected to an Amazon EC2 instance that runs Amazon Linux or Ubuntu Server. If you have a different type of environment or operating system, you might need to adapt this sample's instructions to set up related tools. For more information, see Creating an environment in AWS Cloud9.

  • You have the AWS Cloud9 IDE for the existing environment already open. When you open an environment, AWS Cloud9 opens the IDE for that environment in your web browser. For more information, see Opening an environment in AWS Cloud9.

Step 1: Install g++ and required dev packages

To build and run a C++ application, you need a utility such as g++, which is a C++ compiler provided by the GNU Complier Collection (GCC).

You also need to add header files (-dev packages) for libcurl, libopenssl, libuuid, zlib, and, optionally, libpulse for Amazon Polly support.

The process of installing development tools varies slightly depending on whether you're using an Amazon Linux/Amazon Linux 2 instance or an Ubuntu instance.

Amazon Linux-based systems

You can check if you already have gcc installed by running the following command in the AWS Cloud9 terminal:

g++ --version

If g++ isn't installed, you can easily install it part of the package group called "Development Tools". These tools are added to an instance with the yum groupinstall command:

sudo yum groupinstall "Development Tools"

Run g++ --version again to confirm that the compiler has been installed.

Now install the packages for the required libraries using your system’s package manager: 

sudo yum install libcurl-devel openssl-devel libuuid-devel pulseaudio-libs-devel
Ubuntu-based systems

You can check if you already have gcc installed by running the following command in the AWS Cloud9 terminal:

g++ --version

If gcc is not installed, you can install it on an Ubuntu-based system by running the following commands:

sudo apt update
sudo apt install build-essential
sudo apt-get install manpages-dev

Run g++ --version again to confirm that the compiler has been installed.

Now install the packages for the required libraries using your system’s package manager: 

sudo apt-get install libcurl4-openssl-dev libssl-dev uuid-dev zlib1g-dev libpulse-dev

Step 2: Install CMake

You need to install the cmake tool, which automates the process of building executable files from source code.

  1. In the IDE terminal window, run the following command to obtain the required archive:

    wget https://cmake.org/files/v3.18/cmake-3.18.0.tar.gz

  2. Extract the files from the archive and navigate to the directory that contains the unpacked files:

    tar xzf cmake-3.18.0.tar.gz
cd cmake-3.18.0

  3. Next, run a bootstrap script and install cmake by running the following commands:

    ./bootstrap
make
sudo make install

  4. Confirm you've installed the tool by running the following command:

    cmake --version

Step 3: Obtain and build the SDK for C++

To set up the AWS SDK for C++, you can either build the SDK yourself directly from the source or download the libraries using a package manager. You can find details on the available options in Getting Started Using the AWS SDK for C++ in the AWS SDK for C++ Developer Guide.

This sample demonstrating using git to clone the SDK source code and cmake to build the SDK for C++.

  1. Clone the remote repository and get all git submodules recursively for your AWS Cloud9 environment by running the following command in the terminal:

    git clone --recurse-submodules https://github.com/aws/aws-sdk-cpp

  2. Navigate to the new aws-sdk-cpp directory, create a sub-directory to build the AWS SDK for C++ into, and then navigate to that:

    cd aws-sdk-cpp
mkdir sdk_build
cd sdk_build
  3. Note

    To save time, this step builds only the Amazon S3 portion of the AWS SDK for C++. If you want to build the complete SDK, omit the -DBUILD_ONLY=s3 from the cmake command.

    Building the complete SDK for C++ can take more than an hour to complete, depending on the computing resources available to your Amazon EC2 instance or your own server.

    Use cmake to build the Amazon S3 portion of the SDK for C++ into the sdk_build directory by running the following command:

    cmake .. -DBUILD_ONLY=s3

  4. Now run the make install command so that the built SDK can be accessed:

    sudo make install
cd ..

Step 4: Create C++ and CMakeLists files

In this step, you create a C++ file that allows users of the project to interact with Amazon S3 buckets.

You also create a CMakeLists.txt file that provides instructions that are used by cmake to build your C++ library.

  1. In the AWS Cloud9 IDE, create a file with this content, and save the file with the name s3-demo.cpp at the root (/) of your environment.

    #include <iostream>
#include <aws/core/Aws.h>
#include <aws/s3/S3Client.h>
#include <aws/s3/model/Bucket.h>
#include <aws/s3/model/CreateBucketConfiguration.h>
#include <aws/s3/model/CreateBucketRequest.h>
#include <aws/s3/model/DeleteBucketRequest.h>

// Look for a bucket among all currently available Amazon S3 buckets.
bool FindTheBucket(const Aws::S3::S3Client &s3Client,
                   const Aws::String &bucketName) {

    Aws::S3::Model::ListBucketsOutcome outcome = s3Client.ListBuckets();

    if (outcome.IsSuccess()) {

        std::cout << "Looking for a bucket named '" << bucketName << "'..."
                  << std::endl << std::endl;

        Aws::Vector<Aws::S3::Model::Bucket> bucket_list =
                outcome.GetResult().GetBuckets();

        for (Aws::S3::Model::Bucket const &bucket: bucket_list) {
            if (bucket.GetName() == bucketName) {
                std::cout << "Found the bucket." << std::endl << std::endl;

                return true;
            }
        }

        std::cout << "Could not find the bucket." << std::endl << std::endl;
    }
    else {
        std::cerr << "ListBuckets error: "
                  << outcome.GetError().GetMessage() << std::endl;
    }

    return outcome.IsSuccess();
}

// Create an Amazon S3 bucket.
bool CreateTheBucket(const Aws::S3::S3Client &s3Client,
                     const Aws::String &bucketName,
                     const Aws::String& region) {

    std::cout << "Creating a bucket named '"
              << bucketName << "'..." << std::endl << std::endl;

    Aws::S3::Model::CreateBucketRequest request;
    request.SetBucket(bucketName);

     if (region != "us-east-1") {
        Aws::S3::Model::CreateBucketConfiguration createBucketConfig;
        createBucketConfig.SetLocationConstraint(
                Aws::S3::Model::BucketLocationConstraintMapper::GetBucketLocationConstraintForName(
                        region));
        request.SetCreateBucketConfiguration(createBucketConfig);
    }

    Aws::S3::Model::CreateBucketOutcome outcome =
            s3Client.CreateBucket(request);

    if (outcome.IsSuccess()) {
        std::cout << "Bucket created." << std::endl << std::endl;
    }
    else {
        std::cerr << "CreateBucket error: "
                  << outcome.GetError().GetMessage() << std::endl;
    }

    return outcome.IsSuccess();
}

// Delete an existing Amazon S3 bucket.
bool DeleteTheBucket(const Aws::S3::S3Client &s3Client,
                     const Aws::String &bucketName) {

    std::cout << "Deleting the bucket named '"
              << bucketName << "'..." << std::endl << std::endl;

    Aws::S3::Model::DeleteBucketRequest request;
    request.SetBucket(bucketName);

    Aws::S3::Model::DeleteBucketOutcome outcome =
            s3Client.DeleteBucket(request);

    if (outcome.IsSuccess()) {
        std::cout << "Bucket deleted." << std::endl << std::endl;
    }
    else {
        std::cerr << "DeleteBucket error: "
                  << outcome.GetError().GetMessage() << std::endl;
    }

    return outcome.IsSuccess();
}

#ifndef TESTING_BUILD
// Create an S3 bucket and then delete it.
// Before and after creating the bucket, and again after deleting the bucket,
// try to determine whether that bucket still exists. 
int main(int argc, char *argv[]) {

    if (argc < 3) {
        std::cout << "Usage: s3-demo <bucket name> <AWS Region>" << std::endl
                  << "Example: s3-demo my-bucket us-east-1" << std::endl;
        return 1;
    }

    Aws::SDKOptions options;
    Aws::InitAPI(options);
    {
        Aws::String bucket_name = argv[1];
        Aws::String region = argv[2];

        Aws::Client::ClientConfiguration config;

        config.region = region;

        Aws::S3::S3Client s3_client(config);

        if (!FindTheBucket(s3_client, bucket_name)) {
            return 1;
        }

        if (!CreateTheBucket(s3_client, bucket_name, region)) {
            return 1;
        }

        if (!FindTheBucket(s3_client, bucket_name)) {
            return 1;
        }

        if (!DeleteTheBucket(s3_client, bucket_name)) {
            return 1;
        }

        if (!FindTheBucket(s3_client, bucket_name)) {
            return 1;
        }
    }
    Aws::ShutdownAPI(options);

    return 0;
}
#endif  // TESTING_BUILD

  2. Create a second file with this content, and save the file with the name CMakeLists.txt at the root (/) of your environment. This file enables you to build your code into an executable file.

    # A minimal CMakeLists.txt file for the AWS SDK for C++.

# The minimum version of CMake that will work.
cmake_minimum_required(VERSION 2.8)

# The project name.
project(s3-demo)

# Locate the AWS SDK for C++ package.
set(AWSSDK_ROOT_DIR, "/usr/local/")
set(BUILD_SHARED_LIBS ON)
find_package(AWSSDK REQUIRED COMPONENTS s3)

# The executable name and its source files.
add_executable(s3-demo s3-demo.cpp)

# The libraries used by your executable.
target_link_libraries(s3-demo ${AWSSDK_LINK_LIBRARIES})

Step 5: Build and run the C++ code

  1. In the root directory of your environment in which you've saved the s3-demo.cpp and CMakeLists.txt, run cmake to build your project:

    cmake . 
make

  2. You can now run your program from the command line. In the following command, replace my-unique-bucket-name with a unique name for the Amazon S3 bucket and, if necessary, replace us-east-1 with the identifier of another AWS Region where you want to create a bucket.

    ./s3-demo my-unique-bucket-name us-east-1

    If the program runs successfully, output similar to the following is returned: 

    Looking for a bucket named 'my-unique-bucket-name'...

Could not find the bucket.

Creating a bucket named 'my-unique-bucket-name'...

Bucket created.

Looking for a bucket named 'my-unique-bucket-name'...

Found the bucket.

Deleting the bucket named 'my-unique-bucket-name'...

Bucket deleted.

Looking for a bucket named 'my-unique-bucket-name'...

Could not find the bucket.

Step 6: Clean up

To prevent ongoing charges to your AWS account after you're finished with this sample, delete the environment. For instructions, see Deleting an environment in AWS Cloud9.