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::notebooks_v1::ManagedNotebookServiceClient(
google::cloud::notebooks_v1::MakeManagedNotebookServiceConnection(
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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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, with version-specific information available from 2.11.0 up to the latest release candidate 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eClient libraries typically use Application Default Credentials for authentication, but you can override this by using \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e to load a service account key file, as shown in the provided example.\u003c/p\u003e\n"],["\u003cp\u003eThe provided code example demonstrates how to load a service account key file and create a \u003ccode\u003eManagedNotebookServiceClient\u003c/code\u003e with overridden credentials.\u003c/p\u003e\n"],["\u003cp\u003eExamples are available for \u003ccode\u003eManagedNotebookServiceClient\u003c/code\u003e, \u003ccode\u003eNotebookServiceClient\u003c/code\u003e in \u003ccode\u003enotebooks_v1\u003c/code\u003e, and \u003ccode\u003eNotebookServiceClient\u003c/code\u003e in \u003ccode\u003enotebooks_v2\u003c/code\u003e, and there is a \u003ccode\u003eBest practices\u003c/code\u003e guide for more details on service account key management.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eAuthentication Components\u003c/code\u003e page provides further information on factory functions for creating \u003ccode\u003egoogle::cloud::Credentials\u003c/code\u003e objects.\u003c/p\u003e\n"]]],[],null,[]]
