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::rapidmigrationassessment_v1::
RapidMigrationAssessmentClient(
google::cloud::rapidmigrationassessment_v1::
MakeRapidMigrationAssessmentConnection(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 2025-03-05 UTC."],[[["This page provides documentation for the Rapid Migration Assessment C++ client library, detailing versions ranging from 2.13.0 up to the latest release candidate 2.37.0-rc."],["The library defaults to using Application Default Credentials for authentication with Google Cloud Services, but it supports overriding this behavior."],["You can override the default authentication by utilizing the UnifiedCredentialsOption and providing credentials, such as loading a service account key file, within your application."],["The page includes a code example demonstrating how to load a service account key file for authentication and guidance to consult the documentation for best practices for service account keys."],["Additional information regarding the factory functions to create `google::cloud::Credentials` objects can be found in the Authentication Components documentation."]]],[]]