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 2025-03-14 UTC."],[[["This document provides information on how to override the default Application Default Credentials (ADC) when authenticating with Google Cloud Services."],["You can override the default credentials by providing the `UnifiedCredentialsOption`, as demonstrated with an example of loading a service account key file."],["The latest release candidate version is 2.37.0-rc, while the current document focuses on version 2.31.0, and multiple previous versions are available to browse, down to version 2.13.0."],["Examples are provided for both `metastore_v1::DataprocMetastoreClient` and `metastore_v1::DataprocMetastoreFederationClient` to show how to load service account credentials."],["The document recommends consulting the \"Best practices for managing service account keys\" guide for more details on managing service account credentials and refers to the \"Authentication Components\" section for creating `google::cloud::Credentials` objects."]]],[]]