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::vmmigration_v1::VmMigrationClient(
google::cloud::vmmigration_v1::MakeVmMigrationConnection(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 2025-05-07 UTC."],[[["The latest release candidate version available is 2.37.0-rc, while the most stable release is 2.36.0, with a variety of other versions also available, ranging from 2.35.0 to 2.11.0."],["Client libraries typically use Application Default Credentials (ADC) for authentication with Google Cloud Services, but these can be overridden when necessary."],["Authentication credentials can be overridden by using `UnifiedCredentialsOption`, as demonstrated by the example showing how to explicitly load a service account key file."],["For more information on the factory functions to create `google::cloud::Credentials` objects, refer to the Authentication Components documentation."],["The provided code snippet illustrates how to load a service account key file and create a VmMigrationClient with custom options."]]],[]]
