smrtapi.net

C# client for Speechmatics real time API

Installation

Install-Package Speechmatics

Sample code

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Text;
using Speechmatics.Realtime.Client;
using Newtonsoft.Json;
using Speechmatics.Realtime.Client.Config;

namespace DemoApp
{
    public class Program
    {
        private const string SampleAudio = "2013-8-british-soccer-football-commentary-alex-warner.mp3";

        private static string ToJson(object obj)
        {
            return JsonConvert.SerializeObject(obj);
        }

        private static string RtUrl
        {
            get
            {
                var host = Environment.GetEnvironmentVariable("TEST_HOST") ?? "wss://api.rt.speechmatics.io";
                // Port 9000 for Speechmatics docker containers
                return host.StartsWith("wss://") ? host : $"wss://{host}:9000/";
            }
        }

        public static void Main(string[] args)
        {
            var start = DateTime.Now;
            Debug.WriteLine("Starting at {0}", start);
            var builder = new StringBuilder();
            var language = Environment.GetEnvironmentVariable("LANG") ?? "en";
            Console.WriteLine(language);

            using (var stream = File.Open(SampleAudio, FileMode.Open, FileAccess.Read))
            {
                try
                {

                    var config = new SmRtApiConfig(language)
                    {
                        AuthToken= Environment.GetEnvironmentVariable("AUTH_TOKEN"),
                        // GenerateTempToken = True <- set this to True for accounts from portal.speechmatics.com
                        OutputLocale = "en-GB",
                        AddTranscriptCallback = s => builder.Append(s),
                        AddTranscriptMessageCallback = s => Console.WriteLine(ToJson(s)),
                        AddTranslationMessageCallback = s => Console.WriteLine(ToJson(s)),
                        AddPartialTranscriptMessageCallback = s => Console.WriteLine(ToJson(s)),
                        ErrorMessageCallback = s => Console.WriteLine(ToJson(s)),
                        WarningMessageCallback = s => Console.WriteLine(ToJson(s)),
                        CustomDictionaryPlainWords = new[] {"speechmagic"},
                        CustomDictionarySoundsLikes = new Dictionary<string, IEnumerable<string>>(),
                        Insecure = true,
                        EnablePartials=true,
                        TranslationConfig = new TranslationConfig() {
                            TargetLanguages = new [] {"de"},
                            EnablePartials = true
                        }
                    };

                    // We can do this here, or earlier. It's not used until .Run() is called on the API object.
                    config.CustomDictionarySoundsLikes["gnocchi"] = new[] {"nokey", "noki"};

                    var api = new SmRtApi(RtUrl,
                        stream,
                        config
                    );
                    // Run() will block until the transcription is complete.
                    Console.WriteLine($"Connecting to {RtUrl}");
                    api.Run();
                    Console.WriteLine(builder.ToString());
                }
                catch (AggregateException e)
                {
                    Console.WriteLine(e);
                }
            }

            var finish = DateTime.Now;
            Debug.WriteLine("Starting at {0} -- {1}", finish, finish-start);
            Console.ReadLine();
        }
    }
}

Sample Dockerfile

FROM microsoft/dotnet as build-env
WORKDIR /app

RUN git clone https://github.com/speechmatics/speechmatics-dotnet.git
WORKDIR /app/smrtapi.net/SmRtAPI/DemoAppNetCore
RUN sed -i 's/<SignAssembly>true<\/SignAssembly>/<SignAssembly>false<\/SignAssembly>/' ../SmRtAPI/SpeechmaticsAPI.csproj
RUN dotnet build && dotnet publish -c Release -o out
RUN cp ../DemoApp/*.mp3 ./out

FROM microsoft/dotnet:runtime
WORKDIR /app
COPY --from=build-env /app/smrtapi.net/SmRtAPI/DemoAppNetCore/out ./
ENTRYPOINT ["dotnet", "DemoAppNetCore.dll"]

Building in the CI

For those with direct access to the repository

Any commit on a pull request will trigger Github actions to build and sign a nuget package which can be downloaded as an artifact.

A tagged Github release will be published to nuget.org for tags of the form v\d+.\d+.\d+ and for release candidates or special builds, v\d+.\d+.\d+-*. Examples: 2.0.3, 2.0.5-rc1. To avoid confusion, only tag main, not other branches.

To test the build process without polluting nuget.org (releases cannot be deleted, only 'delisted'), use a tag ending with -test*, for example 2.0.3-testjohnd. This will run the CI for tagged builds but publish to the nuget test repository apiint.nugettest.org.

Testing

TODO

Give this repo an API key for testing against the Speechmatics Realtime SaaS, update the unit tests and run them with dotnet test

Debugging websockets

Merge the following with your app.config file to enable debugging to a file. If you don't have an app.config file, use this XML as-is. This technique will work whether you're building from source or using the Nuget package.

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <system.diagnostics>
    <sources>
      <source name="System.Net" tracemode="includehex" maxdatasize="1024">
        <listeners>
          <add name="System.Net"/>
        </listeners>
      </source>
      <source name="System.Net.Cache">
        <listeners>
          <add name="System.Net"/>
        </listeners>
      </source>
      <source name="System.Net.Http">
        <listeners>
          <add name="System.Net"/>
        </listeners>
      </source>
      <source name="System.Net.Sockets">
        <listeners>
          <add name="System.Net"/>
        </listeners>
      </source>
      <source name="System.Net.WebSockets">
        <listeners>
          <add name="System.Net"/>
        </listeners>
      </source>
    </sources>
    <switches>
      <add name="System.Net" value="Verbose"/>
      <add name="System.Net.Cache" value="Verbose"/>
      <add name="System.Net.Http" value="Verbose"/>
      <add name="System.Net.Sockets" value="Verbose"/>
      <add name="System.Net.WebSockets" value="Verbose"/>
    </switches>
    <sharedListeners>
      <add name="System.Net"
           type="System.Diagnostics.TextWriterTraceListener"
           initializeData="network.log"
      />
    </sharedListeners>
    <trace autoflush="true">
      <listeners>
        <add name="file" type="System.Diagnostics.TextWriterTraceListener" initializeData="trace.log"/>
      </listeners>
    </trace>
    </system.diagnostics>
</configuration>

This will log smrtapi specific information to trace.log (and the output window in Visual Studio, if you're running under a debugger) and all network traffic to network.log.