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 page details how to override the default authentication credentials used by client libraries when interacting with Google Cloud Services, using the `UnifiedCredentialsOption`."],["The latest release candidate version is `2.37.0-rc`, and the page also lists previous versions back to `2.11.0`, with links to each versions documentation."],["The provided code example demonstrates explicitly loading a service account key file to override the default Application Default Credentials (ADC) using `MakeServiceAccountCredentials`."],["Specific examples for `BudgetServiceClient`, `CloudBillingClient`, and `CloudCatalogClient` classes are linked, showcasing how to apply the credential override in different client contexts."],["The page also links to best practices for managing service account keys and other authentication components for more information."]]],[]]