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::networkconnectivity_v1::HubServiceClient(
google::cloud::networkconnectivity_v1::MakeHubServiceConnection(
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 page provides documentation for overriding default authentication credentials when using Google Cloud C++ client libraries for Network Connectivity."],["The latest release is version 2.37.0-rc, and the page lists available versions, ranging from 2.11.0 to the latest, allowing users to access documentation for specific versions."],["Users can override the default [Application Default Credentials](https://cloud.google.com/docs/authentication#adc) by utilizing the `UnifiedCredentialsOption` and providing a service account key file."],["Example code is provided demonstrating how to load a service account key file and use it with the `HubServiceClient`, as well as a link to the `PolicyBasedRoutingServiceClient`."],["The page also contains a link to resources on the best practices for managing service account keys and a link to the Authentication Components page for more information on how to create `google::cloud::Credentials`."]]],[]]