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::batch_v1::BatchServiceClient(
google::cloud::batch_v1::MakeBatchServiceConnection(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 2025-03-05 UTC."],[[["This document provides a comprehensive list of C++ Batch API versions, ranging from version 2.11.0 up to the latest release candidate 2.37.0-rc."],["The default authentication method for client libraries is Application Default Credentials, but users can override this behavior."],["You can explicitly override default credentials by utilizing the `UnifiedCredentialsOption` and loading a service account key file, as demonstrated in the provided example."],["The provided example uses `google::cloud::Options` and `google::cloud::MakeServiceAccountCredentials` to set the proper credentials."],["There is a guide for the best practices of managing service account keys, as well as more information on the Authentication components."]]],[]]