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 versioned documentation for overriding authentication credentials when using Google Cloud C++ client libraries, covering versions from 2.12.0 up to the latest release candidate 2.37.0-rc."],["By default, the client libraries use Application Default Credentials, but you can override this by using `UnifiedCredentialsOption`."],["The document includes an example demonstrating how to load a service account key file to explicitly set authentication credentials."],["The document provides links to relevant external documentation that can provide more information, such as best practices for service account key management and general authentication components."]]],[]]
