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::LoggingServiceV2Client(
google::cloud::logging_v2::MakeLoggingServiceV2Connection(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 provides documentation for overriding default authentication credentials in Google Cloud C++ client libraries for logging services."],["The latest version documented is 2.37.0-rc, with a range of previous versions listed from 2.36.0 down to 2.11.0."],["The client libraries typically use Application Default Credentials, but can be configured to override these defaults via the `UnifiedCredentialsOption`."],["An example demonstrates loading a service account key file to explicitly set credentials using `MakeServiceAccountCredentials`."],["For best practices on managing service account keys, see the linked Google Cloud IAM documentation, and for more information on creating credentials objects, refer to the Authentication Components section."]]],[]]