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 page provides documentation for various versions of the Org Policy C++ client library, ranging from version 2.11.0 to 2.37.0-rc, including links to specific version documentation for overriding authentication.\u003c/p\u003e\n"],["\u003cp\u003eThe latest release candidate version of the documentation covered on this page is 2.37.0-rc, while the latest full release version documented here is 2.36.0.\u003c/p\u003e\n"],["\u003cp\u003eThe documentation details how to override the default Application Default Credentials (ADC) for authenticating with Google Cloud Services, showing an example using a service account key file with the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eThe provided example on overriding default credentials is a simplified illustration, and the user is advised to reference the "Best practices for managing service account keys" for more comprehensive information.\u003c/p\u003e\n"],["\u003cp\u003eAdditional information on creating \u003ccode\u003egoogle::cloud::Credentials\u003c/code\u003e objects can be found in the linked "Authentication Components" section of the documentation.\u003c/p\u003e\n"]]],[],null,["Version 2.17.0keyboard_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."]]