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::kms_inventory_v1::KeyDashboardServiceClient(
google::cloud::kms_inventory_v1::MakeKeyDashboardServiceConnection(
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 version-specific details and examples on how to override default authentication credentials when using Google Cloud client libraries, with the latest release being 2.37.0-rc."],["The content focuses on the `UnifiedCredentialsOption` to override the default [Application Default Credentials](https://cloud.google.com/docs/authentication#adc) for authenticating with Google Cloud services."],["An example is provided to illustrate how to load a service account key file explicitly for authentication, which can be used with various client classes like `KeyDashboardServiceClient`, `KeyTrackingServiceClient`, `EkmServiceClient`, and `KeyManagementServiceClient`."],["The examples provided use relatively simple error handling and link to a best practices guide for managing service account keys, offering further assistance."],["The document also links to the \"Authentication Components\" section for more details on creating `google::cloud::Credentials` objects, providing more in depth explanations."]]],[]]