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 page provides documentation for various versions of the C++ client library, ranging from version 2.11.0 to the latest release candidate 2.37.0-rc, for batch-override-authentication."],["The client libraries primarily use Application Default Credentials for authentication with Google Cloud Services, unless otherwise configured."],["You can override the default authentication method by using the `UnifiedCredentialsOption`, as demonstrated by explicitly loading a service account key file."],["The provided example shows how to override the default credentials by reading the contents of a service account key file and configuring the `UnifiedCredentialsOption` accordingly."],["For detailed information on creating `google::cloud::Credentials` objects, refer to the Authentication Components section."]]],[]]