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::profiler_v2::ExportServiceClient(
google::cloud::profiler_v2::MakeExportServiceConnection(options));
}
Follow these links to find examples for other*Clientclasses:
[[["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 versioned documentation for overriding authentication credentials within the Google Cloud C++ client libraries, covering versions from 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 utilizes Application Default Credentials, but users can override this by employing \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e to specify alternative credentials.\u003c/p\u003e\n"],["\u003cp\u003eThe example in this document demonstrates how to load credentials using a service account key file and apply them when creating a \u003ccode\u003eprofiler_v2::ExportServiceClient\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eExamples for overriding credentials with other client classes, including \u003ccode\u003eprofiler_v2::ProfilerServiceClient\u003c/code\u003e, are linked for further guidance.\u003c/p\u003e\n"],["\u003cp\u003eFor more detailed instructions and best practices related to managing service account keys and creating \u003ccode\u003egoogle::cloud::Credentials\u003c/code\u003e objects, refer to the linked guides.\u003c/p\u003e\n"]]],[],null,["Version 2.33.0keyboard_arrow_down\n\n- [2.42.0-rc (latest)](/cpp/docs/reference/profiler/latest/profiler-override-authentication)\n- [2.41.0](/cpp/docs/reference/profiler/2.41.0/profiler-override-authentication)\n- [2.40.0](/cpp/docs/reference/profiler/2.40.0/profiler-override-authentication)\n- [2.39.0](/cpp/docs/reference/profiler/2.39.0/profiler-override-authentication)\n- [2.38.0](/cpp/docs/reference/profiler/2.38.0/profiler-override-authentication)\n- [2.37.0](/cpp/docs/reference/profiler/2.37.0/profiler-override-authentication)\n- [2.36.0](/cpp/docs/reference/profiler/2.36.0/profiler-override-authentication)\n- [2.35.0](/cpp/docs/reference/profiler/2.35.0/profiler-override-authentication)\n- [2.34.0](/cpp/docs/reference/profiler/2.34.0/profiler-override-authentication)\n- [2.33.0](/cpp/docs/reference/profiler/2.33.0/profiler-override-authentication)\n- [2.32.0](/cpp/docs/reference/profiler/2.32.0/profiler-override-authentication)\n- [2.31.0](/cpp/docs/reference/profiler/2.31.0/profiler-override-authentication)\n- [2.30.0](/cpp/docs/reference/profiler/2.30.0/profiler-override-authentication)\n- [2.29.0](/cpp/docs/reference/profiler/2.29.0/profiler-override-authentication)\n- [2.28.0](/cpp/docs/reference/profiler/2.28.0/profiler-override-authentication)\n- [2.27.0](/cpp/docs/reference/profiler/2.27.0/profiler-override-authentication)\n- [2.26.0](/cpp/docs/reference/profiler/2.26.0/profiler-override-authentication)\n- [2.25.1](/cpp/docs/reference/profiler/2.25.1/profiler-override-authentication)\n- [2.24.0](/cpp/docs/reference/profiler/2.24.0/profiler-override-authentication)\n- [2.23.0](/cpp/docs/reference/profiler/2.23.0/profiler-override-authentication)\n- [2.22.1](/cpp/docs/reference/profiler/2.22.1/profiler-override-authentication)\n- [2.21.0](/cpp/docs/reference/profiler/2.21.0/profiler-override-authentication)\n- [2.20.0](/cpp/docs/reference/profiler/2.20.0/profiler-override-authentication)\n- [2.19.0](/cpp/docs/reference/profiler/2.19.0/profiler-override-authentication)\n- [2.18.0](/cpp/docs/reference/profiler/2.18.0/profiler-override-authentication)\n- [2.17.0](/cpp/docs/reference/profiler/2.17.0/profiler-override-authentication)\n- [2.16.0](/cpp/docs/reference/profiler/2.16.0/profiler-override-authentication)\n- [2.15.1](/cpp/docs/reference/profiler/2.15.1/profiler-override-authentication)\n- [2.14.0](/cpp/docs/reference/profiler/2.14.0/profiler-override-authentication)\n- [2.13.0](/cpp/docs/reference/profiler/2.13.0/profiler-override-authentication)\n- [2.12.0](/cpp/docs/reference/profiler/2.12.0/profiler-override-authentication)\n- [2.11.0](/cpp/docs/reference/profiler/2.11.0/profiler-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::profiler_v2::ExportServiceClient(\n google::cloud::profiler_v2::MakeExportServiceConnection(options));\n }\n\nFollow these links to find examples for other `*Client` classes:\n\n- [`profiler_v2::ExportServiceClient`](/cpp/docs/reference/profiler/2.33.0/profiler_v2_1_1ExportServiceClient-service-account-snippet)\n- [`profiler_v2::ProfilerServiceClient`](/cpp/docs/reference/profiler/2.33.0/profiler_v2_1_1ProfilerServiceClient-service-account-snippet)\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."]]