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::container_v1::ClusterManagerClient(
google::cloud::container_v1::MakeClusterManagerConnection(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 page documents different versions of the C++ container library, ranging from version 2.11.0 up to the latest release candidate, 2.37.0-rc."],["The default authentication method for the client libraries is Application Default Credentials, but this can be overridden if needed."],["To override default credentials, users can use the `UnifiedCredentialsOption` to provide alternate credentials, such as loading a service account key file."],["The provided code example demonstrates how to explicitly load a service account key file to override default credentials using the `UnifiedCredentialsOption`."],["Refer to the \"Best practices for managing service account keys\" guide and \"Authentication Components\" for further details on managing keys and creating `google::cloud::Credentials` objects."]]],[]]