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::cloudbuild_v1::CloudBuildClient(
google::cloud::cloudbuild_v1::MakeCloudBuildConnection(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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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\u003eThis document provides information on how to override the default authentication credentials used by the client libraries when interacting with Google Cloud Services.\u003c/p\u003e\n"],["\u003cp\u003eThe latest release candidate for the cloudbuild documentation is version 2.37.0-rc, while version 2.24.0 is presented as the current release.\u003c/p\u003e\n"],["\u003cp\u003eYou can override the default credentials by using the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e, and an example is provided showing how to load a service account key file.\u003c/p\u003e\n"],["\u003cp\u003eLinks to examples for other client classes like \u003ccode\u003ecloudbuild_v1::CloudBuildClient\u003c/code\u003e and \u003ccode\u003ecloudbuild_v2::RepositoryManagerClient\u003c/code\u003e are available for version 2.24.0.\u003c/p\u003e\n"],["\u003cp\u003eThe document recommends reviewing the "Best practices for managing service account keys" guide for more detailed information and links to "Authentication Components" for more information on creating \u003ccode\u003eCredentials\u003c/code\u003e objects.\u003c/p\u003e\n"]]],[],null,[]]
