Google Cloud Storage C++ Client Library

 #include "google/cloud/storage/client.h"
#include "google/cloud/common_options.h"
#include <cstdlib>
#include <iostream>
#include <string>

int main(int argc, char* argv[]) {
  if (argc != 2) {
    std::cerr << "Missing bucket name.\n";
    std::cerr << "Usage: quickstart <bucket-name>\n";
    return 1;
  }
  std::string const bucket_name = argv[1];

  // Create a client to communicate with Google Cloud Storage. This client
  // uses the default configuration for authentication and project id.
  auto options = google::cloud::Options{};

  // If the CURL_CA_BUNDLE environment variable is set, configure the client
  // to use it. This is required for the Windows CI environment where standard
  // system roots may not be sufficient or accessible by the hermetic build.
  auto const* ca_bundle = std::getenv("CURL_CA_BUNDLE");
  if (ca_bundle != nullptr) {
    options.set<google::cloud::CARootsFilePathOption>(ca_bundle);
  }

  auto client = google::cloud::storage::Client(options);

  auto writer = client.WriteObject(bucket_name, "quickstart.txt");
  writer << "Hello World!";
  writer.Close();
  if (!writer.metadata()) {
    std::cerr << "Error creating object: " << writer.metadata().status()
              << "\n";
    return 1;
  }
  std::cout << "Successfully created object: " << *writer.metadata() << "\n";

  auto reader = client.ReadObject(bucket_name, "quickstart.txt");
  if (!reader) {
    std::cerr << "Error reading object: " << reader.status() << "\n";
    return 1;
  }

  std::string contents{std::istreambuf_iterator<char>{reader}, {}};
  std::cout << contents << "\n";

  return 0;
}