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"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-03-14 UTC."],[[["The latest version available is 2.37.0-rc, with numerous prior versions available ranging from 2.36.0 down to 2.12.0."],["Client libraries generally authenticate using Application Default Credentials, but this can be overridden when needed."],["You can override default credentials using the UnifiedCredentialsOption, such as by loading a service account key file."],["The provided example demonstrates overriding authentication by loading a service account key file, as it is a simple method, but it's recommended to use better methods."],["For more information on creating `google::cloud::Credentials` objects, refer to the Authentication Components section."]]],[]]
