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::servicecontrol_v1::QuotaControllerClient(
google::cloud::servicecontrol_v1::MakeQuotaControllerConnection(
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"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-03-21 UTC."],[[["This page details how to override the default authentication credentials for Google Cloud Services using the `UnifiedCredentialsOption`."],["The latest release is version 2.37.0-rc, and the content also covers multiple versions of the `servicecontrol` library, ranging from 2.11.0 to 2.37.0-rc."],["An example is given demonstrating how to load a service account key file and how to override credentials."],["The `servicecontrol_v1::QuotaControllerClient`, `servicecontrol_v1::ServiceControllerClient`, and `servicecontrol_v2::ServiceControllerClient` classes are exemplified in the documentation as ways to override authentication."],["There are resources to learn more about authentication components and best practices for managing service account keys, including a link to the `Authentication Components` documentation and the `Best practices for managing service account keys` guide."]]],[]]
