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::networkmanagement_v1::ReachabilityServiceClient(
google::cloud::networkmanagement_v1::MakeReachabilityServiceConnection(
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 webpage provides documentation for overriding default authentication credentials when using Google Cloud client libraries, specifically focusing on `networkmanagement`."],["The most recent release candidate is version 2.37.0-rc, with the list of versions spanning from 2.37.0-rc down to 2.11.0, all of which relate to overriding authentication for network management."],["Client libraries typically use Application Default Credentials (ADC), but the `UnifiedCredentialsOption` allows for overriding these defaults, as demonstrated by the service account key file example."],["The provided example uses a service account key file to demonstrate how you can override the default credentials, and it references the best practices guide for managing them for further insight."],["The page refers to the \"Authentication Components\" section of the documentation, for more information on the factory functions to create [`google::cloud::Credentials`] objects."]]],[]]
