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::contentwarehouse_v1::DocumentServiceClient(
google::cloud::contentwarehouse_v1::MakeDocumentServiceConnection(
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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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\u003eThis page provides documentation for overriding default authentication credentials when using Google Cloud client libraries, specifically focusing on the \u003ccode\u003econtentwarehouse\u003c/code\u003e service.\u003c/p\u003e\n"],["\u003cp\u003eThe latest version available is \u003ccode\u003e2.37.0-rc\u003c/code\u003e, but there are many versions listed, ranging from \u003ccode\u003e2.12.0\u003c/code\u003e to \u003ccode\u003e2.36.0\u003c/code\u003e, and including \u003ccode\u003e2.24.0\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eBy setting the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e with the \u003ccode\u003eMakeServiceAccountCredentials\u003c/code\u003e function, you can explicitly load a service account key file for authentication, offering more control than the Application Default Credentials.\u003c/p\u003e\n"],["\u003cp\u003eExamples are provided for various client classes within the \u003ccode\u003econtentwarehouse_v1\u003c/code\u003e namespace, such as \u003ccode\u003eDocumentServiceClient\u003c/code\u003e, \u003ccode\u003eDocumentLinkServiceClient\u003c/code\u003e, and \u003ccode\u003eSynonymSetServiceClient\u003c/code\u003e, to demonstrate overriding authentication.\u003c/p\u003e\n"],["\u003cp\u003eRefer to the "Best practices for managing service account keys" and the "Authentication Components" guide for additional details and managing \u003ccode\u003eCredentials\u003c/code\u003e objects.\u003c/p\u003e\n"]]],[],null,[]]
