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 2025-03-14 UTC."],[[["This page provides documentation for various versions of the C++ client library, ranging from version 2.11.0 up to the release candidate 2.37.0-rc, with each version containing documentation about how to override batch authentication."],["The default authentication method for the client libraries is Application Default Credentials, which may need to be overridden in certain scenarios for a specific authentication."],["The `UnifiedCredentialsOption` is used to override default credentials and can be provided by loading a service account key file, as shown in the example code snippet."],["The included example demonstrates how to explicitly load a service account keyfile using `MakeServiceAccountCredentials`."],["Best practices for managing service account keys can be found in the linked guide, along with additional details on authentication factory functions."]]],[]]