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::run_v2::ExecutionsClient(
google::cloud::run_v2::MakeExecutionsConnection(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 2025-04-09 UTC."],[[["This page details how to override the default Application Default Credentials (ADC) for authenticating with Google Cloud Services when using C++ client libraries."],["You can override the default credentials by using the `UnifiedCredentialsOption` and providing a service account key file."],["The provided example demonstrates how to load a service account key file to create a custom `ExecutionsClient`, overriding default credentials, with a snippet for minimal error handling."],["There are also examples available for other client classes, including `JobsClient`, `RevisionsClient`, `ServicesClient`, and `TasksClient`."],["For a more in depth look into managing service account keys, consult the \"Best practices for managing service account keys\" guide, with more information on creating `Credentials` objects in the \"Authentication Components\" section."]]],[]]
