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::migrationcenter_v1::MigrationCenterClient(
google::cloud::migrationcenter_v1::MakeMigrationCenterConnection(
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 document provides versioned documentation for overriding authentication in the Migration Center, with the latest version being 2.37.0-rc and the oldest listed as 2.13.0."],["Client libraries typically use Application Default Credentials for authentication, but you can override this using the UnifiedCredentialsOption."],["You can override authentication by providing a service account key file, demonstrated through an example that loads credentials from a specified file."],["For detailed information on managing service account keys and creating Credentials objects, refer to the linked \"Best practices\" guide and the \"Authentication Components\" documentation respectively."]]],[]]