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::alloydb_v1::AlloyDBAdminClient(
google::cloud::alloydb_v1::MakeAlloyDBAdminConnection(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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 various versions of the AlloyDB C++ client library, ranging from version 2.11.0 up to the latest release candidate, 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eThe default authentication method for the client libraries is Application Default Credentials, which can be overridden when necessary.\u003c/p\u003e\n"],["\u003cp\u003eYou can override the default authentication by utilizing the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e and providing the service account key file, like demonstrated in the provided code example.\u003c/p\u003e\n"],["\u003cp\u003eThe example on the page shows how to explicitly load a service account key file, which utilizes the \u003ccode\u003eMakeServiceAccountCredentials\u003c/code\u003e function, and is provided as a relatively easy to understand example for how to do so.\u003c/p\u003e\n"],["\u003cp\u003eThe documentation recommends reviewing the "Best practices for managing service account keys" guide for further information on service account key management, and also provides a link for information on how to create credentials objects.\u003c/p\u003e\n"]]],[],null,[]]
