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::networksecurity_v1::NetworkSecurityClient(
google::cloud::networksecurity_v1::MakeNetworkSecurityConnection(
options));
}
[[["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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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\u003eThe latest version available is 2.37.0-rc, with numerous other versions, down to 2.13.0, also listed for reference.\u003c/p\u003e\n"],["\u003cp\u003eClient libraries typically use Application Default Credentials for Google Cloud service authentication, but this can be overridden.\u003c/p\u003e\n"],["\u003cp\u003eYou can override default authentication by utilizing \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e, such as loading a service account key file, as demonstrated in the provided example.\u003c/p\u003e\n"],["\u003cp\u003eThe example given uses the service account key file, but you can use the best practices guide to use other best practices to configure your credentials.\u003c/p\u003e\n"],["\u003cp\u003eFor creating \u003ccode\u003egoogle::cloud::Credentials\u003c/code\u003e objects, consult the Authentication Components section for details on factory functions.\u003c/p\u003e\n"]]],[],null,[]]
