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::beyondcorp_appconnections_v1::
AppConnectionsServiceClient(
google::cloud::beyondcorp_appconnections_v1::
MakeAppConnectionsServiceConnection(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"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14 UTC."],[[["\u003cp\u003eThis page provides documentation for overriding default authentication credentials in Google Cloud C++ client libraries for BeyondCorp services.\u003c/p\u003e\n"],["\u003cp\u003eThe latest release is version 2.37.0-rc, and the page lists available versions of the BeyondCorp C++ client library, with links to each version's documentation.\u003c/p\u003e\n"],["\u003cp\u003eUsers can override the default \u003ca href=\"https://cloud.google.com/docs/authentication#adc\"\u003eApplication Default Credentials\u003c/a\u003e by using the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e and loading a service account key file.\u003c/p\u003e\n"],["\u003cp\u003eThe page includes examples of how to override authentication for various BeyondCorp service clients, such as \u003ccode\u003eAppConnectionsServiceClient\u003c/code\u003e, \u003ccode\u003eAppConnectorsServiceClient\u003c/code\u003e, \u003ccode\u003eAppGatewaysServiceClient\u003c/code\u003e, \u003ccode\u003eClientConnectorServicesServiceClient\u003c/code\u003e, and \u003ccode\u003eClientGatewaysServiceClient\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eFor detailed information and best practices regarding service account keys, users are directed to the "Best practices for managing service account keys" guide, as well as a guide for Authentication Components.\u003c/p\u003e\n"]]],[],null,[]]
