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 2025-03-14 UTC."],[[["This page provides documentation for overriding default authentication credentials when using Google Cloud client libraries, with version-specific information ranging from 2.12.0 to 2.37.0-rc."],["By default, client libraries use Application Default Credentials (ADC) for Google Cloud service authentication, but this can be overridden using the `UnifiedCredentialsOption`."],["An example is given demonstrating how to load a service account key file and explicitly set the authentication options."],["Users are referred to the \"Best practices for managing service account keys\" guide for more comprehensive details on the topic."],["The \"Authentication Components\" section provides information on creating `google::cloud::Credentials` objects."]]],[]]
