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::policytroubleshooter_iam_v3::
PolicyTroubleshooterClient(
google::cloud::policytroubleshooter_iam_v3::
MakePolicyTroubleshooterConnection(options));
}
Follow these links to find examples for other *Client classes:
[[["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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 release candidate for the Policy Troubleshooter documentation is version 2.37.0-rc, with numerous previous versions available, starting from 2.11.0, for reference.\u003c/p\u003e\n"],["\u003cp\u003eBy default, client libraries utilize Application Default Credentials for authentication with Google Cloud Services, but this can be overridden.\u003c/p\u003e\n"],["\u003cp\u003eYou can override the default authentication by supplying the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e, demonstrated via loading a service account key file with example code.\u003c/p\u003e\n"],["\u003cp\u003eExamples for other client classes, such as \u003ccode\u003epolicytroubleshooter_iam_v3::PolicyTroubleshooterClient\u003c/code\u003e and \u003ccode\u003epolicytroubleshooter_v1::IamCheckerClient\u003c/code\u003e, are available for viewing.\u003c/p\u003e\n"],["\u003cp\u003eFor best security practices concerning service account keys, refer to the provided guide, and see the "Authentication Components" for more on creating \u003ccode\u003egoogle::cloud::Credentials\u003c/code\u003e objects.\u003c/p\u003e\n"]]],[],null,[]]
