OAuth2 Access Token Generation Library

This library contains helpers to create OAuth2 access tokens. This may be useful when trying to access customer services deployed to Cloud Run, or when using Google APIs that lack a client library in google-cloud-cpp .

Quickstart

The following shows the code that you'll run in the google/cloud/oauth2/quickstart/ directory. This is the typical usage of the library in applications.

 #include "google/cloud/oauth2/access_token_generator.h"
#include <iostream>

int main(int argc, char* argv[]) try {
  if (argc != 1) {
    std::cerr << "Usage: " << argv[0] << "\n";
    return 1;
  }

  // Use Application Default Credentials to initialize an AccessTokenGenerator
  // retrieve the access token.
  auto credentials = google::cloud::MakeGoogleDefaultCredentials();
  auto generator =
      google::cloud::oauth2::MakeAccessTokenGenerator(*credentials);
  auto token = generator->GetToken();
  if (!token) throw std::move(token).status();
  // Only print the first few characters to avoid leaking tokens in test logs.
  std::cout << "The access token starts with " << token->token.substr(0, 16)
            << "\n";

  return 0;
} catch (google::cloud::Status const& status) {
  std::cerr << "google::cloud::Status thrown: " << status << "\n";
  return 1;
}

Main interfaces

More Information

Error Handling - describes how the library reports errors.
Authentication methods at Google - has more information about authentication and the Application Default credentials