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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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\u003eThis webpage provides documentation for different versions of the Network Security client library, ranging from the latest release candidate \u003ccode\u003e2.37.0-rc\u003c/code\u003e down to version \u003ccode\u003e2.13.0\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eThe library typically uses Application Default Credentials for authentication, but you can override this by providing a \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eYou can explicitly load a service account key file by creating \u003ccode\u003egoogle::cloud::Options\u003c/code\u003e and using \u003ccode\u003eMakeServiceAccountCredentials\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eThe documentation refers to the \u003ca href=\"https://cloud.google.com/iam/docs/best-practices-for-managing-service-account-keys\"\u003eBest practices for managing service account keys\u003c/a\u003e for guidance on handling service account credentials and \u003ca href=\"https://cloud.google.com/cpp/docs/reference/common/latest/group__guac.html\"\u003eAuthentication Components\u003c/a\u003e for details on how to create credentials objects.\u003c/p\u003e\n"]]],[],null,[]]
