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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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\u003eThe webpage provides documentation for various versions of the C++ Access Approval client library, ranging from version 2.11.0 to 2.37.0-rc, with 2.37.0-rc being the latest release candidate.\u003c/p\u003e\n"],["\u003cp\u003eThe client libraries, by default, use Application Default Credentials (ADC) for Google Cloud Services authentication, however there are methods for overriding this behavior.\u003c/p\u003e\n"],["\u003cp\u003eUsers can override the default authentication by utilizing \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e and can explicitly load a service account key file as demonstrated in the code example.\u003c/p\u003e\n"],["\u003cp\u003eThe provided example focuses on overriding authentication through loading a service account key file, but users should refer to the "Best practices for managing service account keys" for detailed guidance.\u003c/p\u003e\n"],["\u003cp\u003eAdditional information on creating \u003ccode\u003egoogle::cloud::Credentials\u003c/code\u003e objects can be found in the "Authentication Components" section of the documentation.\u003c/p\u003e\n"]]],[],null,[]]
