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::automl_v1::AutoMlClient(
google::cloud::automl_v1::MakeAutoMlConnection(options));
}
Follow these links to find examples for other *Client classes:
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14 UTC."],[[["\u003cp\u003eThis page provides documentation for various versions of the AutoML C++ client library, ranging from version 2.11.0 up to the latest release candidate 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eThe documentation explains how to override the default Application Default Credentials (ADC) for Google Cloud Services by using the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eAn example is provided showing how to explicitly load a service account key file to authenticate with Google Cloud.\u003c/p\u003e\n"],["\u003cp\u003eThe page includes links to examples for \u003ccode\u003eautoml_v1::AutoMlClient\u003c/code\u003e and \u003ccode\u003eautoml_v1::PredictionServiceClient\u003c/code\u003e classes, demonstrating service account authentication.\u003c/p\u003e\n"],["\u003cp\u003eIt references best practices for managing service account keys and provides a link to more information on authentication components.\u003c/p\u003e\n"]]],[],null,[]]
