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::resourcesettings_v1::ResourceSettingsServiceClient(
google::cloud::resourcesettings_v1::
MakeResourceSettingsServiceConnection(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 2025-03-21 UTC."],[[["This page provides documentation for overriding default authentication credentials when using Google Cloud client libraries, with version-specific information."],["The latest version available is 2.37.0-rc, and the list contains version documentation from 2.11.0 to the latest, 2.37.0-rc, including some minor releases."],["By default, the client libraries use Application Default Credentials (ADC) for authentication, but you can override this by using the UnifiedCredentialsOption."],["The provided code example demonstrates how to override default credentials by loading a service account key file using `google::cloud::UnifiedCredentialsOption`."],["The page directs users to additional resources for more detailed guidance, including the \"Best practices for managing service account keys\" and \"Authentication Components\"."]]],[]]
