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::logging_v2::ConfigServiceV2Client(
google::cloud::logging_v2::MakeConfigServiceV2Connection(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 2025-04-17 UTC."],[[["This page provides documentation for overriding default authentication credentials in Google Cloud C++ client libraries for logging, allowing the use of service account keys."],["The most recent release candidate version is 2.37.0-rc, and this page includes documentation for versions of the logging client going as far back as 2.11.0."],["The `UnifiedCredentialsOption` is used to override the default authentication, and the provided example demonstrates how to explicitly load a service account key file."],["Specific examples for `ConfigServiceV2Client`, `LoggingServiceV2Client`, and `MetricsServiceV2Client` are available to show how to implement service account authentication."],["Users should consult the \"Best practices for managing service account keys\" guide for more detailed information and security considerations when overriding default credentials."]]],[]]
