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::pubsublite::AdminServiceClient(
google::cloud::pubsublite::MakeAdminServiceConnection(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 2025-03-14 UTC."],[[["This page details how to override the default authentication credentials used by the client libraries when interacting with Google Cloud Services."],["The latest release candidate version is 2.37.0-rc, with multiple other version options available, starting from 2.11.0, which is the oldest documented version on this webpage."],["You can override the default Application Default Credentials by providing the `UnifiedCredentialsOption`, for example, by loading a service account key file."],["Examples for other client classes such as `pubsublite::AdminServiceClient` and `pubsublite::TopicStatsServiceClient` are available for reference, showing how to override authentication."],["The [Authentication Components](https://cloud.google.com/cpp/docs/reference/common/latest/group__guac.html) section provides more information on creating `google::cloud::Credentials` objects."]]],[]]