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::managedkafka_v1::ManagedKafkaClient(
google::cloud::managedkafka_v1::MakeManagedKafkaConnection(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 2025-03-05 UTC."],[[["The latest version of the documentation available is 2.37.0-rc, with numerous other versions available, from 2.36.0 down to 2.26.0."],["Client libraries typically authenticate using Application Default Credentials, but you can override this with the UnifiedCredentialsOption."],["Overriding default credentials can be done by providing a service account key file, as demonstrated in the provided code example."],["The provided code example demonstrates using the `UnifiedCredentialsOption` with a service account key file, to authenticate by loading it from a path."],["For more information about creating Credentials objects, consult the Authentication Components section."]]],[]]
