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::metastore_v1::DataprocMetastoreClient(
google::cloud::metastore_v1::MakeDataprocMetastoreConnection(options));
}
Follow these links to find examples for other *Client classes:
[[["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 2025-04-17 UTC."],[[["This page provides documentation for overriding default authentication credentials when using Google Cloud client libraries, specifically for the Dataproc Metastore service."],["The latest version available is 2.37.0-rc, but this page also provides access to documentation for versions 2.36.0 down to 2.13.0."],["The example demonstrates how to override default credentials by loading a service account key file using `UnifiedCredentialsOption` and the `MakeServiceAccountCredentials` function."],["Links to examples for other client classes like `DataprocMetastoreClient` and `DataprocMetastoreFederationClient` are provided, along with a link to best practices for managing service account keys."],["The content also refers to the Authentication Components page, which provides further information on factory functions for creating `google::cloud::Credentials` objects."]]],[]]
