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 2025-03-05 UTC."],[[["The latest version available is 2.37.0-rc, and there are multiple older versions available, ranging down to version 2.11.0 for the network connectivity documentation."],["By default, client libraries authenticate using Application Default Credentials, but this can be overridden in cases where the default isn't sufficient for the application needs."],["The `UnifiedCredentialsOption` allows users to override default authentication, as shown in the example where a service account key file is explicitly loaded."],["Examples for other `*Client` classes, such as `networkconnectivity_v1::HubServiceClient` and `networkconnectivity_v1::PolicyBasedRoutingServiceClient`, are provided for reference."],["Service account key management best practices are recommended, with a link provided to a guide for further details on managing service account keys."]]],[]]