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\u003eThe webpage provides documentation for various versions of the \u003ccode\u003eorgpolicy-override-authentication\u003c/code\u003e feature, 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 client libraries is Application Default Credentials, but the documentation explains how to override this by using \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eThe documentation includes a code example demonstrating how to load a service account key file to explicitly authenticate.\u003c/p\u003e\n"],["\u003cp\u003eUsers are referred to the "Best practices for managing service account keys" guide for more comprehensive details on the topic.\u003c/p\u003e\n"],["\u003cp\u003eThe "Authentication Components" section provides information on factory functions to create \u003ccode\u003egoogle::cloud::Credentials\u003c/code\u003e objects, offering more in-depth knowledge on the subject.\u003c/p\u003e\n"]]],[],null,["Version 2.22.1keyboard_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."]]