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::binaryauthorization_v1::
BinauthzManagementServiceV1Client(
google::cloud::binaryauthorization_v1::
MakeBinauthzManagementServiceV1Connection(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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 available version is 2.37.0-rc, with numerous other versions, starting at 2.36.0 and going all the way to 2.11.0, available for browsing.\u003c/p\u003e\n"],["\u003cp\u003eClient libraries typically use Application Default Credentials for authentication, but this can be overridden if required for a specific use case.\u003c/p\u003e\n"],["\u003cp\u003eAuthentication can be overridden using \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e, as demonstrated by loading a service account key file in an example.\u003c/p\u003e\n"],["\u003cp\u003eExamples of overriding authentication for \u003ccode\u003eBinauthzManagementServiceV1Client\u003c/code\u003e, \u003ccode\u003eSystemPolicyV1Client\u003c/code\u003e, and \u003ccode\u003eValidationHelperV1Client\u003c/code\u003e are also provided.\u003c/p\u003e\n"],["\u003cp\u003eRefer to the "Best practices for managing service account keys" guide and the "Authentication Components" documentation for more information on service account keys and credentials.\u003c/p\u003e\n"]]],[],null,[]]
