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."],[[["This page provides documentation for overriding default authentication credentials when using Google Cloud client libraries, specifically for the Composer service."],["The latest version documentation available is 2.37.0-rc, and this document includes documentation for versions from 2.11.0 up to 2.37.0-rc, including multiple minor version releases."],["Overriding authentication can be done by providing the `UnifiedCredentialsOption`, exemplified by loading a service account key file via the `MakeServiceAccountCredentials` function."],["Examples for `EnvironmentsClient` and `ImageVersionsClient` classes are provided to demonstrate overriding authentication in specific client contexts."],["The documentation links to the \"Best practices for managing service account keys\" guide and the \"Authentication Components\" for further details on managing service account keys and creating `google::cloud::Credentials` objects."]]],[]]