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::eventarc_publishing_v1::PublisherClient(
google::cloud::eventarc_publishing_v1::MakePublisherConnection(
options));
}
Follow these links to find examples for other *Client classes:
[[["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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 webpage provides documentation for various versions of the Eventarc C++ client library, ranging from version 2.11.0 up to the latest release candidate, 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eThe default authentication for the client libraries uses Application Default Credentials, but can be overridden using the UnifiedCredentialsOption, such as loading a service account key file explicitly.\u003c/p\u003e\n"],["\u003cp\u003eThe content provides a code example demonstrating how to load a service account key file for authentication, offering a practical guide to overriding default credentials.\u003c/p\u003e\n"],["\u003cp\u003eSpecific examples for other \u003ccode\u003e*Client\u003c/code\u003e classes, such as \u003ccode\u003eeventarc_publishing_v1::PublisherClient\u003c/code\u003e and \u003ccode\u003eeventarc_v1::EventarcClient\u003c/code\u003e, can be found through provided links.\u003c/p\u003e\n"],["\u003cp\u003eUsers are advised to review the best practices for managing service account keys for more detailed information on secure authentication procedures.\u003c/p\u003e\n"]]],[],null,[]]
