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::backupdr_v1::BackupDRClient(
google::cloud::backupdr_v1::MakeBackupDRConnection(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 document provides guidance on overriding default authentication credentials for Google Cloud Services when using client libraries."],["Client libraries typically use Application Default Credentials for authentication, but this can be overridden using `UnifiedCredentialsOption`."],["A service account key file can be explicitly loaded to override the default credentials as demonstrated in the provided example code using the function `MakeServiceAccountCredentials`."],["The example code shows how to override authentication using a service account key file, with error handling, and creating a `BackupDRClient` with these options."],["The document links to further resources, including best practices for managing service account keys and information on creating `google::cloud::Credentials` objects."]]],[]]
