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::datastream_v1::DatastreamClient(
google::cloud::datastream_v1::MakeDatastreamConnection(options));
}
[[["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 webpage provides documentation for various versions of the C++ Datastream library, ranging from version 2.11.0 up to the latest release candidate, 2.37.0-rc."],["The default authentication for the client libraries is done via Application Default Credentials, but users can override this by utilizing `UnifiedCredentialsOption`."],["An example is given that shows how to explicitly load a service account key file using `UnifiedCredentialsOption`, `MakeServiceAccountCredentials`, and `Options`."],["Users should consult the \"Best practices for managing service account keys\" guide for guidance on managing service accounts."],["Additional information on creating `google::cloud::Credentials` objects can be found in the Authentication Components section."]]],[]]