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 of the documentation is 2.37.0-rc, and there are many other versions available, ranging down to 2.12.0."],["Client libraries typically use Application Default Credentials for authentication with Google Cloud Services, but this default can be overridden."],["You can override default credentials by providing the UnifiedCredentialsOption, such as loading a service account key file as demonstrated in the example."],["The example uses the UnifiedCredentialsOption to explicitly load a service account key file, which can be customized for individual applications."],["The Authentication Components guide provides more details on creating `google::cloud::Credentials` objects."]]],[]]