Authentication on Google Speech API with gRPC using API key

[Евгений Абрамов]

Hello,

If I use the default authorization to access the Google SpeechAPI, it works:  auto Channel = grpc::CreateChannel("speech.googleapis.com", grpc::GoogleDefaultCredentials());

In the documentation https://cloud.google.com/speech/docs/common/auth, there are three ways to authorization: API Keys, Service Accounts, User Accounts

And authorization with API Keys work fine with REST API.

How can I use the authorization API Key in gRPC API?

Thanks