Unless otherwise configured, the client libraries use Application Default Credentials to authenticate with Google Cloud Services. While this works for most applications, in some cases you may need to override this default. You can do so by providing the UnifiedCredentialsOption The following example shows how to explicitly load a service account key file:
[](std::string const& keyfile) {
auto is = std::ifstream(keyfile);
is.exceptions(std::ios::badbit); // Minimal error handling in examples
auto contents = std::string(std::istreambuf_iterator<char>(is.rdbuf()), {});
auto options =
google::cloud::Options{}.set<google::cloud::UnifiedCredentialsOption>(
google::cloud::MakeServiceAccountCredentials(contents));
return google::cloud::orgpolicy_v2::OrgPolicyClient(
google::cloud::orgpolicy_v2::MakeOrgPolicyConnection(options));
}
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14 UTC."],[[["\u003cp\u003eThe latest available version is 2.37.0-rc, with a history of versions available from 2.36.0 down to 2.11.0.\u003c/p\u003e\n"],["\u003cp\u003eClient libraries default to using Application Default Credentials for authentication with Google Cloud Services, but it is possible to override this default.\u003c/p\u003e\n"],["\u003cp\u003eYou can override the default authentication by utilizing the UnifiedCredentialsOption and providing explicit credentials, such as loading a service account key file.\u003c/p\u003e\n"],["\u003cp\u003eThe example demonstrates how to explicitly load a service account key file for authentication, highlighting that this is just one method and the best practices should be consulted.\u003c/p\u003e\n"],["\u003cp\u003eThe Authentication Components guide provides more information on the factory functions to create \u003ccode\u003egoogle::cloud::Credentials\u003c/code\u003e objects.\u003c/p\u003e\n"]]],[],null,[]]