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::privateca_v1::CertificateAuthorityServiceClient(
google::cloud::privateca_v1::MakeCertificateAuthorityServiceConnection(
options));
}
[[["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 2025-04-17 UTC."],[[["The documentation covers versions of the C++ client library for Private CA, ranging from version 2.11.0 up to the release candidate 2.37.0-rc."],["The default authentication method for the client libraries is Application Default Credentials, which can be overridden for specific use cases."],["Authentication credentials can be overridden by utilizing the `UnifiedCredentialsOption`, such as loading a service account key file."],["The example shows how to load a service account key file, with a note that it's a simple example for clarity, and the user should consult the documentation on best practices for service account key management."],["Additional details on factory functions for `google::cloud::Credentials` objects are available in the Authentication Components section of the documentation."]]],[]]
