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::translate_v3::TranslationServiceClient(
google::cloud::translate_v3::MakeTranslationServiceConnection(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 webpage provides documentation for different versions of the C++ client library, ranging from version 2.11.0 up to the release candidate 2.37.0-rc, with each version linked to its corresponding documentation on overriding authentication."],["The documentation explains how to override the default Application Default Credentials (ADC) for authenticating with Google Cloud Services using the `UnifiedCredentialsOption`."],["A code example demonstrates how to load a service account key file to explicitly set the authentication credentials."],["The page refers users to a guide about the best practices for managing service account keys, in addition to other authentication components for more information."]]],[]]
