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 2025-03-21 UTC."],[[["The latest version available is 2.37.0-rc, with numerous preceding versions down to 2.11.0 also accessible."],["The client libraries generally use Application Default Credentials for Google Cloud service authentication, but this can be overridden."],["To override the default authentication, you can use UnifiedCredentialsOption, such as loading a service account key file as an alternative method."],["The provided example demonstrates overriding authentication by loading a service account key file, and it is advised to consult best practices for service account key management."],["For further details on creating `google::cloud::Credentials` objects, refer to the Authentication Components documentation."]]],[]]