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::netapp_v1::NetAppClient(
google::cloud::netapp_v1::MakeNetAppConnection(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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 document provides a guide on how to override default authentication credentials when using client libraries to interact with Google Cloud Services.\u003c/p\u003e\n"],["\u003cp\u003eThe client libraries typically use Application Default Credentials (ADC), but users can override this by using the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eAn example is provided showing how to load a service account key file for explicit authentication.\u003c/p\u003e\n"],["\u003cp\u003eThe document also contains a list of versions ranging from 2.16.0 up to 2.37.0-rc, and the corresponding links for each version's documentation on overriding authentication.\u003c/p\u003e\n"],["\u003cp\u003eThe recommended reading for more information includes the "Best practices for managing service account keys" guide and the "Authentication Components" section.\u003c/p\u003e\n"]]],[],null,[]]
