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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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\u003eThis page provides documentation for the Policy Troubleshooter service, with versions ranging from 2.11.0 up to the latest release candidate, 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eThe default authentication method for client libraries is Application Default Credentials, but they can be overridden for specific use cases.\u003c/p\u003e\n"],["\u003cp\u003eOverriding the default authentication can be done by utilizing the UnifiedCredentialsOption and providing a service account key file.\u003c/p\u003e\n"],["\u003cp\u003eExamples of how to load a service account key file are available for \u003ccode\u003epolicytroubleshooter_iam_v3::PolicyTroubleshooterClient\u003c/code\u003e and \u003ccode\u003epolicytroubleshooter_v1::IamCheckerClient\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eUsers should refer to the "Best practices for managing service account keys" guide for security considerations and further details on key management.\u003c/p\u003e\n"]]],[],null,[]]
