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 2025-03-14 UTC."],[[["The webpage provides a list of available versions for Rapid Migration Assessment, ranging from version 2.13.0 up to the latest release candidate 2.37.0-rc."],["The primary function detailed is how to override the default Application Default Credentials (ADC) for authentication with Google Cloud Services."],["Users can override authentication by providing a `UnifiedCredentialsOption`, such as loading a service account key file, as demonstrated in the example code snippet."],["The content recommends reviewing the \"Best practices for managing service account keys\" guide for more detailed information on security."],["The `Authentication Components` link provides more information on the factory functions used to create `google::cloud::Credentials` objects."]]],[]]
