README.md

.NET Speechly Api

Install the Speechly API stubs with

dotnet add package SpeechlyApi

Importing namespaces

using Grpc.Net.Client;
using Grpc.Core;
using Speechly.Identity.V1;
using Speechly.Slu.V1;

IdentityAPI

Logging in with IdentityAPI is a single RPC call with appId and deviceId.

GrpcChannel channel = GrpcChannel.ForAddress("https://api.speechly.com");
Identity.IdentityClient identityClient = new Identity.IdentityClient(channel);

var deviceId = System.Guid.NewGuid().ToString();

var loginRquest = new LoginRequest
{
    AppId = appId,
    DeviceId = deviceId
};

var response = await identityClient.LoginAsync(loginRquest);

var token = response.Token;

SLU

Streaming SLU is a bidirectional RPC call to the API, which means that it is not no simple as the login example above. Use the token from the Identity response to create the channel for the SLUClient.

var authInterceptor = new AsyncAuthInterceptor(async (context, metadata) =>
{
    metadata.Add(
        new Metadata.Entry("Authorization", "Bearer " + token));
});

var metadataCredentials = CallCredentials.FromInterceptor(authInterceptor);
ChannelCredentials channelCredentials = ChannelCredentials.Create(new SslCredentials(), metadataCredentials);
Channel channel = new Channel("api.speechly.com", channelCredentials);
SLU.SLUClient sluClient = new SLU.SLUClient(channel);
AsyncDuplexStreamingCall<SLURequest, SLUResponse> call = sluClient.Stream();

Start context

Before starting context need to send SLUConfig with Encoding, LanguageCode and SampleRateHertz.

SLURequest configRequest = new SLURequest
{
    Config = new SLUConfig
    {
        Encoding = SLUConfig.Types.Encoding.Linear16,
        LanguageCode = "en-US",
        SampleRateHertz = 16_000,
    }
};

call.RequestStream.WriteAsync(configRequest).Wait();

SLURequest startRequest = new SLURequest
{
    Event = new SLUEvent { Event = SLUEvent.Types.Event.Start }
};
call.RequestStream.WriteAsync(startRequest).Wait();

Send audio

Audio should be sent as a ByteString. In the example audioChunk is a byte[].

SLURequest audio = new SLURequest
{
    Audio = ByteString.CopyFrom(audioChunk)
};

call.RequestStream.WriteAsync(audio).Wait();

Stop context

SLURequest stopRequest = new SLURequest
{
    Event = new SLUEvent { Event = SLUEvent.Types.Event.Stop }
};

call.RequestStream.WriteAsync(stopRequest).Wait();