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::datastore_admin_v1::DatastoreAdminClient(
google::cloud::datastore_admin_v1::MakeDatastoreAdminConnection(
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 2025-03-05 UTC."],[[["The latest version available is 2.37.0-rc, with a history of versions down to 2.15.1 accessible via links."],["Client libraries typically use Application Default Credentials, but these can be overridden using `UnifiedCredentialsOption`."],["Service account key files can be loaded to override the default credentials, as demonstrated in the provided code example."],["Examples for overriding credentials are provided for both `datastore_admin_v1::DatastoreAdminClient` and `datastore_v1::DatastoreClient` classes."],["For best practices on managing service account keys, users are directed to the relevant Google Cloud documentation, while `Authentication Components` provides information for creating `google::cloud::Credentials` objects."]]],[]]