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::servicedirectory_v1::LookupServiceClient(
google::cloud::servicedirectory_v1::MakeLookupServiceConnection(
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 2025-03-14 UTC."],[[["This page provides documentation for overriding default authentication credentials when using Google Cloud client libraries, specifically focusing on Service Directory in C++."],["The latest release candidate for Service Directory is version 2.37.0-rc, with a history of versions available from 2.11.0 up to 2.36.0."],["Client libraries typically use Application Default Credentials for authentication, but `UnifiedCredentialsOption` can be used to override these defaults, such as by loading a service account key file."],["Examples are provided for overriding credentials with `LookupServiceClient` and `RegistrationServiceClient` classes within Service Directory."],["For more information on creating `google::cloud::Credentials` objects and managing service account keys, refer to the linked \"Authentication Components\" and \"Best practices for managing service account keys\" guides."]]],[]]