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::developerconnect_v1::DeveloperConnectClient(
google::cloud::developerconnect_v1::MakeDeveloperConnectConnection(
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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 of the documentation is 2.37.0-rc, with previous versions from 2.36.0 down to 2.27.0 also available.\u003c/p\u003e\n"],["\u003cp\u003eBy default, client libraries authenticate using Application Default Credentials, but you can override this if needed.\u003c/p\u003e\n"],["\u003cp\u003eYou can override default authentication by utilizing the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e, such as by explicitly loading a service account key file.\u003c/p\u003e\n"],["\u003cp\u003eThe provided code snippet shows an example of loading a service account key file, but it's recommended to consult the "Best practices for managing service account keys" guide for more in-depth details.\u003c/p\u003e\n"],["\u003cp\u003eFor additional details on creating \u003ccode\u003egoogle::cloud::Credentials\u003c/code\u003e objects, refer to the Authentication Components documentation.\u003c/p\u003e\n"]]],[],null,[]]
