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::composer_v1::EnvironmentsClient(
google::cloud::composer_v1::MakeEnvironmentsConnection(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."],[[["The latest version available is 2.37.0-rc, with numerous prior versions, ranging from 2.36.0 down to 2.11.0, also accessible."],["By default, client libraries use Application Default Credentials for authentication with Google Cloud Services, but this can be overridden when necessary."],["You can override the default authentication by utilizing `UnifiedCredentialsOption`, as demonstrated in the provided service account key file example."],["Examples for other `*Client` classes, such as `composer_v1::EnvironmentsClient` and `composer_v1::ImageVersionsClient`, are available via provided links."],["Further details and best practices for managing service account keys are available in the linked guide, and more information on `google::cloud::Credentials` objects are available in the Authentication Components section."]]],[]]