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::domains_v1::DomainsClient(
google::cloud::domains_v1::MakeDomainsConnection(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."],[[["This document provides version-specific details for overriding authentication in the Google Cloud C++ client library, including links for versions ranging from 2.12.0 to 2.36.0, and also 2.37.0-rc as the latest version."],["The default authentication method for client libraries uses Application Default Credentials, but you can override this by providing a UnifiedCredentialsOption."],["An example demonstrates overriding authentication by explicitly loading a service account key file, which is a simple method but may not always be the most secure option."],["For additional information on creating Credentials objects, refer to the \"Authentication Components\" section."],["Users should consult the \"Best practices for managing service account keys\" guide for more robust security practices."]]],[]]
