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::SpeechClient(
google::cloud::speech_v1::MakeSpeechConnection(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 documents how to override the default authentication credentials used by the client libraries when interacting with Google Cloud Services, which typically rely on Application Default Credentials."],["You can override the default credentials by using the `UnifiedCredentialsOption`, as demonstrated in the provided example that shows how to explicitly load a service account key file."],["Examples for overriding authentication are available for both `speech_v1::SpeechClient` and `speech_v2::SpeechClient` classes, linked within the documentation."],["The example provided is easy to understand, but for best practices on service account key management, refer to the linked guide on managing service account keys."],["More information on creating `google::cloud::Credentials` objects can be found in the linked \"Authentication Components\" section."]]],[]]
