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 lists different versions of the Storage Control documentation, ranging from version 2.21.0 to the latest release candidate 2.37.0-rc."],["The client libraries primarily utilize Application Default Credentials for authenticating with Google Cloud Services, but this default can be overridden."],["You can override default authentication by supplying the UnifiedCredentialsOption, and the document shows how to use a service account key file for explicit authentication."],["The provided example demonstrates using the `MakeServiceAccountCredentials` function to override authentication, reading the contents from a service key file."],["Best practices for managing service accounts keys are provided in another document, and links to other information on Authentication Components is provided in a See Also section."]]],[]]
