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 2025-03-21 UTC."],[[["The latest version available is 2.37.0-rc, with numerous prior versions available down to 2.13.0."],["The document explains how to override the default Application Default Credentials using UnifiedCredentialsOption when authenticating with Google Cloud Services."],["The example provided demonstrates how to load a service account key file for authentication using the `google::cloud::MakeServiceAccountCredentials` function."],["It is suggested to check out best practices for managing service account keys, and the authentication components for further details."]]],[]]
