Unless otherwise configured, the client libraries useApplication Default Credentialsto 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 theUnifiedCredentialsOptionThe 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::orgpolicy_v2::OrgPolicyClient(
google::cloud::orgpolicy_v2::MakeOrgPolicyConnection(options));
}
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-09-04 UTC."],[[["\u003cp\u003eThis document provides a reference for the \u003ccode\u003eorgpolicy-override-authentication\u003c/code\u003e feature, covering versions from 2.11.0 to the latest release candidate 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eBy default, client libraries use Application Default Credentials for authentication with Google Cloud Services, but this can be overridden if necessary.\u003c/p\u003e\n"],["\u003cp\u003eYou can override the default authentication by supplying a \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e, such as loading a service account key file explicitly, which is demonstrated in the provided example code.\u003c/p\u003e\n"],["\u003cp\u003eFor detailed information on managing service account keys, refer to the "Best practices for managing service account keys" guide, and for details on creating \u003ccode\u003egoogle::cloud::Credentials\u003c/code\u003e objects, consult the Authentication Components documentation.\u003c/p\u003e\n"]]],[],null,["Version 2.35.0keyboard_arrow_down\n\n- [2.42.0-rc (latest)](/cpp/docs/reference/orgpolicy/latest/orgpolicy-override-authentication)\n- [2.41.0](/cpp/docs/reference/orgpolicy/2.41.0/orgpolicy-override-authentication)\n- [2.40.0](/cpp/docs/reference/orgpolicy/2.40.0/orgpolicy-override-authentication)\n- [2.39.0](/cpp/docs/reference/orgpolicy/2.39.0/orgpolicy-override-authentication)\n- [2.38.0](/cpp/docs/reference/orgpolicy/2.38.0/orgpolicy-override-authentication)\n- [2.37.0](/cpp/docs/reference/orgpolicy/2.37.0/orgpolicy-override-authentication)\n- [2.36.0](/cpp/docs/reference/orgpolicy/2.36.0/orgpolicy-override-authentication)\n- [2.35.0](/cpp/docs/reference/orgpolicy/2.35.0/orgpolicy-override-authentication)\n- [2.34.0](/cpp/docs/reference/orgpolicy/2.34.0/orgpolicy-override-authentication)\n- [2.33.0](/cpp/docs/reference/orgpolicy/2.33.0/orgpolicy-override-authentication)\n- [2.32.0](/cpp/docs/reference/orgpolicy/2.32.0/orgpolicy-override-authentication)\n- [2.31.0](/cpp/docs/reference/orgpolicy/2.31.0/orgpolicy-override-authentication)\n- [2.30.0](/cpp/docs/reference/orgpolicy/2.30.0/orgpolicy-override-authentication)\n- [2.29.0](/cpp/docs/reference/orgpolicy/2.29.0/orgpolicy-override-authentication)\n- [2.28.0](/cpp/docs/reference/orgpolicy/2.28.0/orgpolicy-override-authentication)\n- [2.27.0](/cpp/docs/reference/orgpolicy/2.27.0/orgpolicy-override-authentication)\n- [2.26.0](/cpp/docs/reference/orgpolicy/2.26.0/orgpolicy-override-authentication)\n- [2.25.1](/cpp/docs/reference/orgpolicy/2.25.1/orgpolicy-override-authentication)\n- [2.24.0](/cpp/docs/reference/orgpolicy/2.24.0/orgpolicy-override-authentication)\n- [2.23.0](/cpp/docs/reference/orgpolicy/2.23.0/orgpolicy-override-authentication)\n- [2.22.1](/cpp/docs/reference/orgpolicy/2.22.1/orgpolicy-override-authentication)\n- [2.21.0](/cpp/docs/reference/orgpolicy/2.21.0/orgpolicy-override-authentication)\n- [2.20.0](/cpp/docs/reference/orgpolicy/2.20.0/orgpolicy-override-authentication)\n- [2.19.0](/cpp/docs/reference/orgpolicy/2.19.0/orgpolicy-override-authentication)\n- [2.18.0](/cpp/docs/reference/orgpolicy/2.18.0/orgpolicy-override-authentication)\n- [2.17.0](/cpp/docs/reference/orgpolicy/2.17.0/orgpolicy-override-authentication)\n- [2.16.0](/cpp/docs/reference/orgpolicy/2.16.0/orgpolicy-override-authentication)\n- [2.15.1](/cpp/docs/reference/orgpolicy/2.15.1/orgpolicy-override-authentication)\n- [2.14.0](/cpp/docs/reference/orgpolicy/2.14.0/orgpolicy-override-authentication)\n- [2.13.0](/cpp/docs/reference/orgpolicy/2.13.0/orgpolicy-override-authentication)\n- [2.12.0](/cpp/docs/reference/orgpolicy/2.12.0/orgpolicy-override-authentication)\n- [2.11.0](/cpp/docs/reference/orgpolicy/2.11.0/orgpolicy-override-authentication) \n\nHow to Override the Authentication Credentials\n==============================================\n\nUnless otherwise configured, the client libraries use [Application Default Credentials](https://cloud.google.com/docs/authentication#adc) 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](https://cloud.google.com/cpp/docs/reference/common/latest/structgoogle_1_1cloud_1_1UnifiedCredentialsOption.html) The following example shows how to explicitly load a service account key file: \n\n [](std::string const& keyfile) {\n auto is = std::ifstream(keyfile);\n is.exceptions(std::ios::badbit); // Minimal error handling in examples\n auto contents = std::string(std::istreambuf_iterator\u003cchar\u003e(is.rdbuf()), {});\n auto options =\n google::cloud::Options{}.set\u003cgoogle::cloud::UnifiedCredentialsOption\u003e(\n google::cloud::MakeServiceAccountCredentials(contents));\n return google::cloud::orgpolicy_v2::OrgPolicyClient(\n google::cloud::orgpolicy_v2::MakeOrgPolicyConnection(options));\n }\n\nKeep in mind that we chose this as an example because it is relatively easy to understand. Consult the [Best practices for managing service account keys](https://cloud.google.com/iam/docs/best-practices-for-managing-service-account-keys) guide for more details.\n\n###### See Also\n\n[Authentication Components](https://cloud.google.com/cpp/docs/reference/common/latest/group__guac.html) - for more information on the factory functions to create [`google::cloud::Credentials`](https://cloud.google.com/cpp/docs/reference/common/latest/classgoogle_1_1cloud_1_1Credentials.html) objects."]]