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::billing_budgets_v1::BudgetServiceClient(
google::cloud::billing_budgets_v1::MakeBudgetServiceConnection(
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 webpage provides documentation for overriding default authentication credentials in Google Cloud C++ client libraries, using `UnifiedCredentialsOption`."],["The content details how to explicitly load a service account key file for authentication, replacing the use of Application Default Credentials."],["The latest release candidate version for billing-override-authentication is 2.37.0-rc, with a history of versions dating back to 2.11.0 available for reference."],["The page includes code examples demonstrating how to implement service account authentication with various client classes like `BudgetServiceClient`, `CloudBillingClient`, and `CloudCatalogClient`."],["The provided documentation directs users to best practices for managing service account keys and additional information on creating `google::cloud::Credentials` objects."]]],[]]