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::workstations_v1::WorkstationsClient(
google::cloud::workstations_v1::MakeWorkstationsConnection(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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 document outlines how to override the default authentication credentials used by client libraries when interacting with Google Cloud Services.\u003c/p\u003e\n"],["\u003cp\u003eThe latest version of the documentation is 2.37.0-rc, and there is also information available for a range of previous versions, all the way down to version 2.11.0.\u003c/p\u003e\n"],["\u003cp\u003eYou can override the default by providing a \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e, demonstrated through an example that loads a service account key file.\u003c/p\u003e\n"],["\u003cp\u003eThe provided example shows how to load service account credentials, but users are encouraged to review best practices for managing service account keys.\u003c/p\u003e\n"],["\u003cp\u003eFor further details, users can reference the Authentication Components documentation, which details the factory functions to create \u003ccode\u003egoogle::cloud::Credentials\u003c/code\u003e objects.\u003c/p\u003e\n"]]],[],null,[]]
