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::kms_inventory_v1::KeyDashboardServiceClient(
google::cloud::kms_inventory_v1::MakeKeyDashboardServiceConnection(
options));
}
Follow these links to find examples for other *Client classes:
[[["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 document provides information on how to override the default authentication credentials used by client libraries when interacting with Google Cloud Services."],["The default authentication method utilizes Application Default Credentials, but users can override this by using the UnifiedCredentialsOption."],["The provided example demonstrates how to load a service account key file to override the default authentication."],["Links to examples for other Client classes such as KeyDashboardServiceClient, KeyTrackingServiceClient, EkmServiceClient, and KeyManagementServiceClient, are available within this document."],["Users are encouraged to review the Best practices for managing service account keys guide for detailed information on service account key management, and to check the Authentication Components for more details on factory functions."]]],[]]