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::dataplex_v1::ContentServiceClient(
google::cloud::dataplex_v1::MakeContentServiceConnection(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 within the context of the Dataplex service.\u003c/p\u003e\n"],["\u003cp\u003eThe most recent release candidate version is 2.37.0-rc, and a list of previous versions, dating back to version 2.11.0, with their corresponding documentation links is provided.\u003c/p\u003e\n"],["\u003cp\u003eYou can override default authentication by providing the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e and there is an example of loading a service account key file, using \u003ccode\u003eMakeServiceAccountCredentials\u003c/code\u003e, to accomplish this.\u003c/p\u003e\n"],["\u003cp\u003eExamples are provided for \u003ccode\u003eContentServiceClient\u003c/code\u003e, \u003ccode\u003eDataplexServiceClient\u003c/code\u003e, and \u003ccode\u003eMetadataServiceClient\u003c/code\u003e classes to demonstrate the application of service account credentials.\u003c/p\u003e\n"],["\u003cp\u003eIt's recommended to consult the "Best practices for managing service account keys" guide and the "Authentication Components" documentation for more detailed information on managing credentials.\u003c/p\u003e\n"]]],[],null,["Version 2.17.0keyboard_arrow_down\n\n- [2.42.0-rc (latest)](/cpp/docs/reference/dataplex/latest/dataplex-override-authentication)\n- [2.41.0](/cpp/docs/reference/dataplex/2.41.0/dataplex-override-authentication)\n- [2.40.0](/cpp/docs/reference/dataplex/2.40.0/dataplex-override-authentication)\n- [2.39.0](/cpp/docs/reference/dataplex/2.39.0/dataplex-override-authentication)\n- [2.38.0](/cpp/docs/reference/dataplex/2.38.0/dataplex-override-authentication)\n- [2.37.0](/cpp/docs/reference/dataplex/2.37.0/dataplex-override-authentication)\n- [2.36.0](/cpp/docs/reference/dataplex/2.36.0/dataplex-override-authentication)\n- [2.35.0](/cpp/docs/reference/dataplex/2.35.0/dataplex-override-authentication)\n- [2.34.0](/cpp/docs/reference/dataplex/2.34.0/dataplex-override-authentication)\n- [2.33.0](/cpp/docs/reference/dataplex/2.33.0/dataplex-override-authentication)\n- [2.32.0](/cpp/docs/reference/dataplex/2.32.0/dataplex-override-authentication)\n- [2.31.0](/cpp/docs/reference/dataplex/2.31.0/dataplex-override-authentication)\n- [2.30.0](/cpp/docs/reference/dataplex/2.30.0/dataplex-override-authentication)\n- [2.29.0](/cpp/docs/reference/dataplex/2.29.0/dataplex-override-authentication)\n- [2.28.0](/cpp/docs/reference/dataplex/2.28.0/dataplex-override-authentication)\n- [2.27.0](/cpp/docs/reference/dataplex/2.27.0/dataplex-override-authentication)\n- [2.26.0](/cpp/docs/reference/dataplex/2.26.0/dataplex-override-authentication)\n- [2.25.1](/cpp/docs/reference/dataplex/2.25.1/dataplex-override-authentication)\n- [2.24.0](/cpp/docs/reference/dataplex/2.24.0/dataplex-override-authentication)\n- [2.23.0](/cpp/docs/reference/dataplex/2.23.0/dataplex-override-authentication)\n- [2.22.1](/cpp/docs/reference/dataplex/2.22.1/dataplex-override-authentication)\n- [2.21.0](/cpp/docs/reference/dataplex/2.21.0/dataplex-override-authentication)\n- [2.20.0](/cpp/docs/reference/dataplex/2.20.0/dataplex-override-authentication)\n- [2.19.0](/cpp/docs/reference/dataplex/2.19.0/dataplex-override-authentication)\n- [2.18.0](/cpp/docs/reference/dataplex/2.18.0/dataplex-override-authentication)\n- [2.17.0](/cpp/docs/reference/dataplex/2.17.0/dataplex-override-authentication)\n- [2.16.0](/cpp/docs/reference/dataplex/2.16.0/dataplex-override-authentication)\n- [2.15.1](/cpp/docs/reference/dataplex/2.15.1/dataplex-override-authentication)\n- [2.14.0](/cpp/docs/reference/dataplex/2.14.0/dataplex-override-authentication)\n- [2.13.0](/cpp/docs/reference/dataplex/2.13.0/dataplex-override-authentication)\n- [2.12.0](/cpp/docs/reference/dataplex/2.12.0/dataplex-override-authentication)\n- [2.11.0](/cpp/docs/reference/dataplex/2.11.0/dataplex-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::dataplex_v1::ContentServiceClient(\n google::cloud::dataplex_v1::MakeContentServiceConnection(options));\n }\n\nFollow these links to find examples for other `*Client` classes:\n\n- [`dataplex_v1::ContentServiceClient`](/cpp/docs/reference/dataplex/2.17.0/dataplex_v1_1_1ContentServiceClient-service-account-snippet)\n- [`dataplex_v1::DataplexServiceClient`](/cpp/docs/reference/dataplex/2.17.0/dataplex_v1_1_1DataplexServiceClient-service-account-snippet)\n- [`dataplex_v1::MetadataServiceClient`](/cpp/docs/reference/dataplex/2.17.0/dataplex_v1_1_1MetadataServiceClient-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."]]