This directory contains an idiomatic C++ client library for interacting with Google Cloud Storage (GCS), which is Google's Object Storage service. It allows world-wide storage and retrieval of any amount of data at any time. You can use Cloud Storage for a range of scenarios including serving website content, storing data for archival and disaster recovery, or distributing large data objects to users via direct download.

Please note that the Google Cloud C++ client libraries do not follow Semantic Versioning.

• Windows, macOS, Linux
• C++11 (and higher) compilers (we test with GCC >= 4.9, Clang >= 3.8, and MSVC >= 2019)
• Environments with or without exceptions
• Bazel and CMake builds

• Official documentation about Google Cloud Storage
• Reference doxygen documentation for each release of this client library
• Detailed header comments in our public .h files

The quickstart/ directory contains a minimal environment to get started using this client library in a larger project. The following "Hello World" program is used in this quickstart, and should give you a taste of this library.

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

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 aliases to make the code easier to read.
  namespace gcs = google::cloud::storage;

  // Create a client to communicate with Google Cloud Storage. This client
  // uses the default configuration for authentication and project id.
  google::cloud::StatusOr<gcs::Client> client =
      gcs::Client::CreateDefaultClient();
  if (!client) {
    std::cerr << "Failed to create Storage Client, status=" << client.status()
              << "\n";
    return 1;
  }

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

  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;
}

• Packaging maintainers or developers that prefer to install the library in a fixed directory (such as /usr/local or /opt) should consult the packaging guide.
• Developers wanting to use the libraries as part of a larger CMake or Bazel project should consult the quickstart guides for the library or libraries they want to use.
• Developers wanting to compile the library just to run some of the examples or tests should read the current document.
• Contributors and developers to google-cloud-cpp should consult the guide to setup a development workstation.

See CONTRIBUTING.md for details on how to contribute to this project, including how to build and test your changes as well as how to properly format your code.

Apache 2.0; see LICENSE for details.