google-cloud-cpp

HOWTO: using the OAuth2 Access Token Generation in your project

This directory contains small examples showing how to use the OAuth2 generator in your own project. These instructions assume that you have some experience as a C++ developer and that you have a working C++ toolchain (compiler, linker, etc.) installed on your platform.

Configuring authentication for the C++ Client Library

Using this library to create OAuth2 tokens requires that you configure your development (or production) environment to work with Google Cloud authentication. If you are not familiar with GCP authentication please take this opportunity to review the Authentication Overview.

The most common configuration is to use Application Default Credentials, see Authentication methods at Google for more information.

Using with Bazel

:warning: If you are using Windows or macOS there are additional instructions at the end of this document.

  1. Install Bazel using the instructions from the bazel.build website.

  2. Compile this example using Bazel:

    cd $HOME/google-cloud-cpp/google/cloud/oauth2/quickstart
    bazel build ...
    

    Note that Bazel automatically downloads and compiles all dependencies of the project. As it is often the case with C++ libraries, compiling these dependencies may take several minutes.

  3. Run the example, changing the placeholder(s) to appropriate values:

    bazel run :quickstart
    

Using with CMake

:warning: If you are using Windows or macOS there are additional instructions at the end of this document.

  1. Install CMake. The package managers for most Linux distributions include a package for CMake. Likewise, you can install CMake on Windows using a package manager such as chocolatey, and on macOS using homebrew. You can also obtain the software directly from the cmake.org.

  2. Install the dependencies with your favorite tools. As an example, if you use vcpkg1:

    cd $HOME/vcpkg
    ./vcpkg install google-cloud-cpp[core,oauth2]
    

    Note that, as it is often the case with C++ libraries, compiling these dependencies may take several minutes.

  3. Configure CMake, if necessary, configure the directory where you installed the dependencies:

    cd $HOME/google-cloud-cpp/google/cloud/oauth2/quickstart
    cmake -S . -B .build -DCMAKE_TOOLCHAIN_FILE=$HOME/vcpkg/scripts/buildsystems/vcpkg.cmake
    cmake --build .build
    
  4. Run the example, changing the placeholder(s) to appropriate values:

    .build/quickstart
    

Platform Specific Notes

Windows

Bazel tends to create very long file names and paths. You may need to use a short directory to store the build output, such as c:\b, and instruct Bazel to use it via:

bazel --output_user_root=c:\b build ...
  1. Sometimes package managers, such as vcpkg, are behind the latest release of google-cloud-cpp and may not have the latest features available.