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::accessapproval_v1::AccessApprovalClient(
google::cloud::accessapproval_v1::MakeAccessApprovalConnection(
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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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\u003eThis page provides documentation for various versions of the Access Approval C++ client library, ranging from version 2.11.0 up to the latest release candidate, 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eThe client libraries typically use Application Default Credentials for authentication, but it's possible to override this behavior when necessary.\u003c/p\u003e\n"],["\u003cp\u003eYou can override the default authentication by utilizing \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e, as demonstrated in the provided code example.\u003c/p\u003e\n"],["\u003cp\u003eThe provided example shows how to load a service account key file to override default authentication credentials, while additional details can be found in the linked guide "Best practices for managing service account keys".\u003c/p\u003e\n"],["\u003cp\u003eThe "Authentication Components" section, located under the "See Also" header, offers supplementary information on creating \u003ccode\u003egoogle::cloud::Credentials\u003c/code\u003e objects using factory functions.\u003c/p\u003e\n"]]],[],null,[]]
