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::networkservices_v1::DepServiceClient(
google::cloud::networkservices_v1::MakeDepServiceConnection(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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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\u003eThe latest version available for network services is 2.37.0-rc, with previous versions listed from 2.36.0 down to 2.12.0.\u003c/p\u003e\n"],["\u003cp\u003eBy default, client libraries authenticate using Application Default Credentials, but you can override this with \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eOverriding default credentials can be done by providing a service account key file, as demonstrated in the example code using \u003ccode\u003eMakeServiceAccountCredentials\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eExamples are provided for both \u003ccode\u003enetworkservices_v1::DepServiceClient\u003c/code\u003e and \u003ccode\u003enetworkservices_v1::NetworkServicesClient\u003c/code\u003e to show how to use service account credentials.\u003c/p\u003e\n"],["\u003cp\u003eFor managing service account keys, refer to the best practices guide, and for more information on creating credentials, check the Authentication Components section.\u003c/p\u003e\n"]]],[],null,[]]
