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 document provides a version history for the Service Directory C++ client library, with version 2.37.0-rc being the latest release candidate."],["The content demonstrates how to override default authentication using the `UnifiedCredentialsOption` by loading a service account key file, as default authentication uses Application Default Credentials."],["Examples are given for the `servicedirectory_v1::LookupServiceClient` and `servicedirectory_v1::RegistrationServiceClient` classes on how to implement this override."],["The document includes links to additional information on authentication, referencing the [Authentication Components](https://cloud.google.com/cpp/docs/reference/common/latest/group__guac.html) page for further details."],["Users are encouraged to follow the best practices for service account keys that are linked in the document."]]],[]]