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 page provides documentation for overriding default authentication credentials when using Google Cloud client libraries, specifically focusing on the profiler service.\u003c/p\u003e\n"],["\u003cp\u003eThe latest release candidate for the profiler service is version 2.37.0-rc, while version 2.32.0 is presented as the current page's version with a dropdown to access previous versions.\u003c/p\u003e\n"],["\u003cp\u003eClient libraries use Application Default Credentials unless explicitly configured otherwise, and overriding involves using the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eThe documentation provides code examples for loading a service account key file and demonstrates this with the \u003ccode\u003eExportServiceClient\u003c/code\u003e and \u003ccode\u003eProfilerServiceClient\u003c/code\u003e classes, showing the implementation of service account credentials.\u003c/p\u003e\n"],["\u003cp\u003eIt is advised to refer to the best practices guide for managing service account keys, and links are provided for additional information regarding authentication components and factory functions to create \u003ccode\u003egoogle::cloud::Credentials\u003c/code\u003e objects.\u003c/p\u003e\n"]]],[],null,["Version 2.32.0keyboard_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/2.32.0/profiler_v2_1_1ExportServiceClient-service-account-snippet)\n- [`profiler_v2::ProfilerServiceClient`](/cpp/docs/reference/profiler/2.32.0/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."]]