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::video_livestream_v1::LivestreamServiceClient(
google::cloud::video_livestream_v1::MakeLivestreamServiceConnection(
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 lists different versions of the C++ video library, ranging from version 2.11.0 up to the latest release candidate 2.37.0-rc, each with a link to documentation regarding video override authentication.\u003c/p\u003e\n"],["\u003cp\u003eThe client libraries primarily use Application Default Credentials for authentication with Google Cloud Services, but you can override this by using the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eAn example is provided demonstrating how to explicitly load a service account key file using \u003ccode\u003egoogle::cloud::MakeServiceAccountCredentials\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eExamples are available for other client classes such as \u003ccode\u003evideo_livestream_v1::LivestreamServiceClient\u003c/code\u003e, \u003ccode\u003evideo_stitcher_v1::VideoStitcherServiceClient\u003c/code\u003e, and \u003ccode\u003evideo_transcoder_v1::TranscoderServiceClient\u003c/code\u003e which are linked on this page.\u003c/p\u003e\n"],["\u003cp\u003eFor more information on managing service account keys or creating credentials objects, refer to the provided links to Google Cloud's best practices and Authentication Components.\u003c/p\u003e\n"]]],[],null,["Version 2.13.0keyboard_arrow_down\n\n- [2.42.0-rc (latest)](/cpp/docs/reference/video/latest/video-override-authentication)\n- [2.41.0](/cpp/docs/reference/video/2.41.0/video-override-authentication)\n- [2.40.0](/cpp/docs/reference/video/2.40.0/video-override-authentication)\n- [2.39.0](/cpp/docs/reference/video/2.39.0/video-override-authentication)\n- [2.38.0](/cpp/docs/reference/video/2.38.0/video-override-authentication)\n- [2.37.0](/cpp/docs/reference/video/2.37.0/video-override-authentication)\n- [2.36.0](/cpp/docs/reference/video/2.36.0/video-override-authentication)\n- [2.35.0](/cpp/docs/reference/video/2.35.0/video-override-authentication)\n- [2.34.0](/cpp/docs/reference/video/2.34.0/video-override-authentication)\n- [2.33.0](/cpp/docs/reference/video/2.33.0/video-override-authentication)\n- [2.32.0](/cpp/docs/reference/video/2.32.0/video-override-authentication)\n- [2.31.0](/cpp/docs/reference/video/2.31.0/video-override-authentication)\n- [2.30.0](/cpp/docs/reference/video/2.30.0/video-override-authentication)\n- [2.29.0](/cpp/docs/reference/video/2.29.0/video-override-authentication)\n- [2.28.0](/cpp/docs/reference/video/2.28.0/video-override-authentication)\n- [2.27.0](/cpp/docs/reference/video/2.27.0/video-override-authentication)\n- [2.26.0](/cpp/docs/reference/video/2.26.0/video-override-authentication)\n- [2.25.1](/cpp/docs/reference/video/2.25.1/video-override-authentication)\n- [2.24.0](/cpp/docs/reference/video/2.24.0/video-override-authentication)\n- [2.23.0](/cpp/docs/reference/video/2.23.0/video-override-authentication)\n- [2.22.1](/cpp/docs/reference/video/2.22.1/video-override-authentication)\n- [2.21.0](/cpp/docs/reference/video/2.21.0/video-override-authentication)\n- [2.20.0](/cpp/docs/reference/video/2.20.0/video-override-authentication)\n- [2.19.0](/cpp/docs/reference/video/2.19.0/video-override-authentication)\n- [2.18.0](/cpp/docs/reference/video/2.18.0/video-override-authentication)\n- [2.17.0](/cpp/docs/reference/video/2.17.0/video-override-authentication)\n- [2.16.0](/cpp/docs/reference/video/2.16.0/video-override-authentication)\n- [2.15.1](/cpp/docs/reference/video/2.15.1/video-override-authentication)\n- [2.14.0](/cpp/docs/reference/video/2.14.0/video-override-authentication)\n- [2.13.0](/cpp/docs/reference/video/2.13.0/video-override-authentication)\n- [2.12.0](/cpp/docs/reference/video/2.12.0/video-override-authentication)\n- [2.11.0](/cpp/docs/reference/video/2.11.0/video-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::video_livestream_v1::LivestreamServiceClient(\n google::cloud::video_livestream_v1::MakeLivestreamServiceConnection(\n options));\n }\n\nFollow these links to find examples for other `*Client` classes:\n\n- [`video_livestream_v1::LivestreamServiceClient`](/cpp/docs/reference/video/2.13.0/video_livestream_v1_1_1LivestreamServiceClient-service-account-snippet)\n- [`video_stitcher_v1::VideoStitcherServiceClient`](/cpp/docs/reference/video/2.13.0/video_stitcher_v1_1_1VideoStitcherServiceClient-service-account-snippet)\n- [`video_transcoder_v1::TranscoderServiceClient`](/cpp/docs/reference/video/2.13.0/video_transcoder_v1_1_1TranscoderServiceClient-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."]]