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 2025-03-21 UTC."],[[["This page lists different versions of the Google Cloud C++ client library, with the latest version being 2.37.0-rc, and each link directs to documentation on overriding authentication for that specific version."],["The default authentication method for the client libraries is Application Default Credentials, but users can override this by using `UnifiedCredentialsOption`."],["An example of overriding the default credentials involves loading a service account key file and setting the `UnifiedCredentialsOption`."],["Links to examples for overriding authentication are provided for various client classes, such as `ExecutionsClient`, `JobsClient`, `RevisionsClient`, `ServicesClient`, and `TasksClient`."],["The `Authentication Components` section provides information about creating `google::cloud::Credentials` objects."]]],[]]