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::apigateway_v1::ApiGatewayServiceClient(
google::cloud::apigateway_v1::MakeApiGatewayServiceConnection(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."],[[["The latest version available is 2.37.0-rc, with a comprehensive list of previous versions ranging down to 2.11.0, all providing documentation on overriding authentication for the API Gateway service."],["The client libraries typically use Application Default Credentials for Google Cloud Services authentication, but this default can be overridden."],["You can override the default authentication by utilizing the UnifiedCredentialsOption, as demonstrated in the provided code example using a service account key file."],["The example in the document shows how to explicitly load a service account key file to authenticate, offering a straightforward method for overriding default credentials."],["For further details on managing service account keys and creating `google::cloud::Credentials` objects, you can refer to the linked guide and the Authentication Components documentation, respectively."]]],[]]