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::MakeGatewayControlConnectionRest(
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."],[[["This page details how to override the default authentication credentials used by the client libraries when interacting with Google Cloud Services, which typically rely on Application Default Credentials."],["You can override the default credentials by using the `UnifiedCredentialsOption`, as demonstrated by the example of loading a service account key file."],["The latest version for this content is 2.37.0-rc, and there are also previous versions available starting from version 2.36.0 down to version 2.29.0."],["For more information on managing service account keys, the page recommends consulting the \"Best practices for managing service account keys\" guide."],["Further details on the factory functions to create `google::cloud::Credentials` objects can be found in the \"Authentication Components\" section."]]],[]]