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::dataplex_v1::ContentServiceClient(
google::cloud::dataplex_v1::MakeContentServiceConnection(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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 page provides documentation for overriding default authentication credentials in the Google Cloud C++ client libraries for Dataplex services.\u003c/p\u003e\n"],["\u003cp\u003eThe latest version documented is 2.37.0-rc, and the content also lists available documentation for versions ranging from 2.11.0 up to 2.36.0, all of which pertain to overriding authentication for Dataplex services.\u003c/p\u003e\n"],["\u003cp\u003eIt details how to override default credentials using \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e, with a specific example of loading a service account key file.\u003c/p\u003e\n"],["\u003cp\u003eExamples of how to override credentials are provided for \u003ccode\u003eContentServiceClient\u003c/code\u003e, \u003ccode\u003eDataplexServiceClient\u003c/code\u003e, and \u003ccode\u003eMetadataServiceClient\u003c/code\u003e classes.\u003c/p\u003e\n"],["\u003cp\u003eIt references best practices for service account key management and offers a link to further information on authentication components within the C++ client library.\u003c/p\u003e\n"]]],[],null,[]]
