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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 various versions of the Content Warehouse C++ client library, ranging from version 2.12.0 up to the latest release candidate, 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eThe client libraries typically use Application Default Credentials for authentication, but these defaults can be overridden when needed.\u003c/p\u003e\n"],["\u003cp\u003eOverriding authentication can be done by utilizing the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e and providing a service account key file.\u003c/p\u003e\n"],["\u003cp\u003eExamples of how to override authentication for different \u003ccode\u003e*Client\u003c/code\u003e classes, such as \u003ccode\u003eDocumentServiceClient\u003c/code\u003e, \u003ccode\u003eDocumentLinkServiceClient\u003c/code\u003e, and others, are available.\u003c/p\u003e\n"],["\u003cp\u003eUsers are advised to consult the "Best practices for managing service account keys" guide for detailed information regarding service account key management.\u003c/p\u003e\n"]]],[],null,[]]
