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::cloudquotas_v1::CloudQuotasClient(
google::cloud::cloudquotas_v1::MakeCloudQuotasConnection(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."],[[["The latest version available is 2.37.0-rc, with a series of previous versions ranging down to 2.20.0, all linked to documentation on overriding authentication."],["By default, client libraries authenticate using Application Default Credentials, but users can override this through the `UnifiedCredentialsOption`."],["Overriding authentication can be achieved by providing a service account key file, as demonstrated in the provided code example using `MakeServiceAccountCredentials`."],["Users should refer to the \"Best practices for managing service account keys\" guide for detailed information on managing service account keys."],["For further details on creating `google::cloud::Credentials` objects, users can consult the \"Authentication Components\" documentation."]]],[]]
