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::gkeconnect_gateway_v1::GatewayControlClient(
google::cloud::gkeconnect_gateway_v1::MakeGatewayControlConnection(
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 2025-03-21 UTC."],[[["This document provides information on how to override the default authentication credentials used by client libraries when interacting with Google Cloud Services."],["The client libraries typically use Application Default Credentials for authentication, but this can be overridden by using the `UnifiedCredentialsOption`."],["An example is provided showing how to load a service account key file for explicit authentication."],["The document references a guide for best practices in managing service account keys and further information on `google::cloud::Credentials`."],["The different versions of the documentation, ranging from version 2.29.0 to 2.37.0-rc, are listed for reference."]]],[]]
