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::recommender_v1::RecommenderClient(
google::cloud::recommender_v1::MakeRecommenderConnection(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."],[[["This page lists documentation for various versions of the C++ Recommender client library, ranging from version 2.11.0 to the latest release candidate 2.37.0-rc."],["The client libraries default to using Application Default Credentials for Google Cloud Service authentication, but this can be overridden."],["You can override the default authentication by utilizing the UnifiedCredentialsOption and providing service account credentials, such as by loading a service account key file, as shown in the example."],["The provided example showcases a simple way to load service account credentials from a key file, but the document recommends consulting best practices for managing service account keys for more advanced scenarios."],["The Authentication Components section has additional details regarding factory functions for creating `google::cloud::Credentials` objects."]]],[]]
