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::commerce_consumer_procurement_v1::
ConsumerProcurementServiceClient(
google::cloud::commerce_consumer_procurement_v1::
MakeConsumerProcurementServiceConnection(options));
}
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14 UTC."],[[["\u003cp\u003eThe latest version of the documentation is 2.37.0-rc, with a full listing of versions ranging from 2.37.0-rc down to 2.14.0.\u003c/p\u003e\n"],["\u003cp\u003eClient libraries typically use Application Default Credentials for authentication with Google Cloud Services, but this can be overridden when necessary.\u003c/p\u003e\n"],["\u003cp\u003eYou can override default authentication by using the UnifiedCredentialsOption, such as explicitly loading a service account key file.\u003c/p\u003e\n"],["\u003cp\u003eThe provided example is using the ConsumerProcurementServiceClient, and the guide offers information about factory functions for creating Credentials objects.\u003c/p\u003e\n"],["\u003cp\u003eConsult the Best practices for managing service account keys guide for detailed information on handling service account keys.\u003c/p\u003e\n"]]],[],null,[]]