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::trace_v1::TraceServiceClient(
google::cloud::trace_v1::MakeTraceServiceConnection(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 2025-03-21 UTC."],[[["The webpage provides documentation for overriding default authentication credentials when interacting with Google Cloud Services, using Application Default Credentials."],["The latest version available is 2.37.0-rc, and the documentation lists multiple past versions, ranging back to version 2.11.0, allowing users to review changes and updates over time."],["Users can override the default authentication by providing a `UnifiedCredentialsOption`, demonstrated through an example that loads a service account key file."],["The content provides links to specific examples for `trace_v1::TraceServiceClient` and `trace_v2::TraceServiceClient` to help with implementation."],["The page also references and recommends the \"Best practices for managing service account keys\" guide for more security details and the \"Authentication Components\" page for more details on factory functions."]]],[]]
