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::secretmanager_v1::SecretManagerServiceClient(
google::cloud::secretmanager_v1::MakeSecretManagerServiceConnection(
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 details how to override the default authentication credentials used by client libraries when interacting with Google Cloud Services."],["The latest version of the documentation available on this page is 2.37.0-rc, while the oldest available version is 2.10.1."],["The `UnifiedCredentialsOption` allows users to customize authentication, such as explicitly loading a service account key file as demonstrated in the provided example code."],["Users can find more information about factory functions for creating `google::cloud::Credentials` objects in the Authentication Components section."],["The default authentication method is Application Default Credentials, and the provided method is an override, with users needing to refer to best practices to properly manage these service account keys."]]],[]]