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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 explains how to override the default authentication credentials, which are typically Application Default Credentials, when interacting with Google Cloud services.\u003c/p\u003e\n"],["\u003cp\u003eYou can override authentication by utilizing the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e and providing a service account key file, as demonstrated in the provided C++ example.\u003c/p\u003e\n"],["\u003cp\u003eThe provided example shows how to load a service account key file and create a \u003ccode\u003eBackupForGKEClient\u003c/code\u003e with custom authentication.\u003c/p\u003e\n"],["\u003cp\u003eFor more information on creating \u003ccode\u003egoogle::cloud::Credentials\u003c/code\u003e objects and managing service account keys, refer to the linked documentation on Authentication Components and best practices.\u003c/p\u003e\n"]]],[],null,[]]
