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::storagecontrol_v2::StorageControlClient(
google::cloud::storagecontrol_v2::MakeStorageControlConnection(
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."],[[["This page provides documentation for various versions of the Storage Control client library, ranging from version 2.21.0 up to the release candidate 2.37.0-rc."],["The default authentication method for the client libraries is Application Default Credentials, but this can be overridden."],["Authentication credentials can be explicitly set by utilizing the `UnifiedCredentialsOption`, such as by loading a service account key file."],["Best practices for managing service account keys are advised, and the Authentication Components section provides further details on creating `google::cloud::Credentials` objects."]]],[]]