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::dataproc_v1::AutoscalingPolicyServiceClient(
google::cloud::dataproc_v1::MakeAutoscalingPolicyServiceConnection(
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 Application Default Credentials (ADC) for authenticating with Google Cloud Services using the C++ client libraries, specifically within the context of Dataproc."],["The latest release is version 2.37.0-rc, while the currently shown documentation is for version 2.12.0, which is one of the versions with available documentation, along with other versions ranging from 2.11.0 up to the latest release."],["You can override authentication by providing a `UnifiedCredentialsOption`, as demonstrated in the example with loading a service account key file."],["The documentation provides specific examples for several Dataproc client classes, including `AutoscalingPolicyServiceClient`, `BatchControllerClient`, `ClusterControllerClient`, `JobControllerClient`, and `WorkflowTemplateServiceClient`."],["For further information on creating `google::cloud::Credentials` objects and best practices for managing service account keys, links to the \"Authentication Components\" and \"Best practices for managing service account keys\" guides are provided."]]],[]]
