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::baremetalsolution_v2::BareMetalSolutionClient(
google::cloud::baremetalsolution_v2::MakeBareMetalSolutionConnection(
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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 webpage lists different versions of the BareMetalSolution documentation, ranging from version 2.11.0 up to the latest release candidate 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eThe default method for authentication with Google Cloud Services is through Application Default Credentials, but there is information on how to override this.\u003c/p\u003e\n"],["\u003cp\u003eYou can override the default authentication by utilizing the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e, and it includes an example of how to load a service account key file.\u003c/p\u003e\n"],["\u003cp\u003eFor detailed guidance on managing service account keys, it is recommended to review the "Best practices for managing service account keys" guide.\u003c/p\u003e\n"],["\u003cp\u003eAdditional information on creating \u003ccode\u003egoogle::cloud::Credentials\u003c/code\u003e objects is available in the "Authentication Components" section.\u003c/p\u003e\n"]]],[],null,[]]
