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::managedidentities_v1::ManagedIdentitiesServiceClient(
google::cloud::managedidentities_v1::
MakeManagedIdentitiesServiceConnection(options));
}
[[["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 webpage provides documentation for various versions of the Google Cloud C++ client library, ranging from version 2.11.0 up to the latest release candidate 2.37.0-rc, for the `managedidentities` component."],["The `managedidentities` client libraries typically use Application Default Credentials (ADC) for authentication with Google Cloud Services, but users can override this default if needed."],["Overriding the default authentication credentials involves providing the `UnifiedCredentialsOption`, such as loading a service account key file, which is illustrated with a code example."],["The example showcases how to load a service account key file using `MakeServiceAccountCredentials` and setting it in the `Options` when creating a `ManagedIdentitiesServiceClient`."],["Users can refer to the Authentication Components documentation for more information on creating `google::cloud::Credentials` objects, and the best practices for service account key management is also linked for further details."]]],[]]