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::gkebackup_v1::BackupForGKEClient(
google::cloud::gkebackup_v1::MakeBackupForGKEConnection(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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 provides documentation for various versions of the \u003ccode\u003egkebackup\u003c/code\u003e service, ranging from version 2.12.0 up to the latest release candidate, 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eThe content includes information on how to override default authentication credentials, offering instructions on using \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e and providing an example using a service account key file.\u003c/p\u003e\n"],["\u003cp\u003eThe document references \u003ccode\u003eApplication Default Credentials\u003c/code\u003e as the default authentication method used by the client libraries when interacting with Google Cloud Services.\u003c/p\u003e\n"],["\u003cp\u003eThere is a recommendation to refer to the "Best practices for managing service account keys" guide for detailed information regarding service account key management.\u003c/p\u003e\n"],["\u003cp\u003eAdditional information on the factory functions for creating credentials objects can be found in the "Authentication Components" section.\u003c/p\u003e\n"]]],[],null,[]]
