Unless otherwise configured, the client libraries use Application Default Credentials 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 The 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::speech_v1::AdaptationClient(
google::cloud::speech_v1::MakeAdaptationConnection(options));
}
Follow these links to find examples for other *Client classes:
[[["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 2025-03-21 UTC."],[[["This page details how to override default authentication credentials for Google Cloud Services, which typically rely on Application Default Credentials."],["You can override the default credentials by using the `UnifiedCredentialsOption` and providing service account details, like loading a service account key file."],["The latest version listed is 2.37.0-rc, while the page content is focused on version 2.18.0, where examples are shown for `speech_v1::AdaptationClient`, `speech_v1::SpeechClient`, and `speech_v2::SpeechClient`."],["Best practices for managing service account keys are recommended to be reviewed for optimal security, in addition to the authentication components page for more in depth information."]]],[]]