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 C++ Managed Identities client library, ranging from version 2.11.0 up to the latest release candidate 2.37.0-rc."],["The client libraries default to using Application Default Credentials for authenticating with Google Cloud Services, but this can be overridden when necessary."],["Users can override the default credentials by utilizing the `UnifiedCredentialsOption`, as demonstrated by the example showing how to explicitly load a service account key file."],["The provided example showcases a simplified approach to credential management, and it is recommended to consult the \"Best practices for managing service account keys\" guide for more detailed information."],["Additional information regarding the creation of `google::cloud::Credentials` objects can be found in the linked \"Authentication Components\" section."]]],[]]