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 page provides documentation for various versions of the Google Cloud C++ client library, ranging from version 2.11.0 up to the latest release candidate 2.37.0-rc."],["The primary focus is on how to override the default authentication credentials, which by default use Application Default Credentials, with custom settings."],["Users can override authentication by using the `UnifiedCredentialsOption` and providing a service account key file, as demonstrated in the provided code example."],["The documentation advises consulting the \"Best practices for managing service account keys\" guide for in-depth information on managing service account credentials."],["Further details on creating `google::cloud::Credentials` objects can be found in the \"Authentication Components\" section of the documentation."]]],[]]
