Setup SignalR and Service Bus inside a Azure Service Fabric service

问题

I am porting an existing Cloud Service WorkerRole to Service Fabric as a stateless service. The original Cloud Service uses SignalR and Service Bus (as a SignalR backplane), to send notifications out to any client listening. There is a Startup class that does some of the setup:

class Startup
{
    public void Configuration(IAppBuilder app)
    {
        String connectionString = "Endpoint=sb://[name].servicebus.windows.net/;SharedSecretIssuer=owner;SharedSecretValue=[key]";
        GlobalHost.DependencyResolver.UseServiceBus(connectionString, "InSys");
        app.MapSignalR();
        Notifications.Hub = GlobalHost.ConnectionManager.GetHubContext<MyHub>();
    }
}

In the OnStart() method in for the WorkerRole I kick-off OWIN with:

var endpoint = RoleEnvironment.CurrentRoleInstance.InstanceEndpoints["HttpEndpoint"];
var baseUri = $"{endpoint.Protocol}://{endpoint.IPEndpoint}";
var app = WebApp.Start<Startup>(new StartOptions(url: baseUri));

How is this (i.e., connection the to SignalR Service Bus Backplane) done for a stateless service within Service Fabric?

回答1:

With the help of https://github.com/marcinbudny/SignalRSelfHostScaleOut (which is an example of scaleout using Redis) I think I have this licked.

In the ServiceManifest.xml I added the following EndPoint:

<Endpoint Protocol="http" Name="ServiceEndpoint" Type="Input" Port="8322" />

I also added a Startup class:

public static class Startup
{
    public static void ConfigureApp(IAppBuilder app)
    {
        String connectionString = "Endpoint=sb://[name].servicebus.windows.net/;SharedSecretIssuer=owner;SharedSecretValue=[value]";
        GlobalHost.DependencyResolver.UseServiceBus(connectionString, "InSys");
        app.MapSignalR();
        Notifications.Hub = GlobalHost.ConnectionManager.GetHubContext<InSysMainHub>();
    }
}

An OwinCommunicationListener class was also added:

public class OwinCommunicationListener : ICommunicationListener
{
    private readonly ServiceEventSource eventSource;
    private readonly Action<IAppBuilder> startup;
    private readonly ServiceContext serviceContext;
    private readonly string endpointName;
    private readonly string appRoot;

    private IDisposable webApp;
    private string publishAddress;
    private string listeningAddress;

    public OwinCommunicationListener(Action<IAppBuilder> startup, ServiceContext serviceContext, ServiceEventSource eventSource, string endpointName)
        : this(startup, serviceContext, eventSource, endpointName, null)
    {
    }

    public OwinCommunicationListener(Action<IAppBuilder> startup, ServiceContext serviceContext, ServiceEventSource eventSource, string endpointName, string appRoot)
    {
        if (startup == null)
        {
            throw new ArgumentNullException(nameof(startup));
        }

        if (serviceContext == null)
        {
            throw new ArgumentNullException(nameof(serviceContext));
        }

        if (endpointName == null)
        {
            throw new ArgumentNullException(nameof(endpointName));
        }

        if (eventSource == null)
        {
            throw new ArgumentNullException(nameof(eventSource));
        }

        this.startup = startup;
        this.serviceContext = serviceContext;
        this.endpointName = endpointName;
        this.eventSource = eventSource;
        this.appRoot = appRoot;
    }


    public Task<string> OpenAsync(CancellationToken cancellationToken)
    {
        var serviceEndpoint = this.serviceContext.CodePackageActivationContext.GetEndpoint(this.endpointName);
        var protocol = serviceEndpoint.Protocol;
        int port = serviceEndpoint.Port;

        if (this.serviceContext is StatefulServiceContext)
        {
            StatefulServiceContext statefulServiceContext = (StatefulServiceContext) serviceContext;

            listeningAddress = string.Format(
                CultureInfo.InvariantCulture,
                "{0}://+:{1}/{2}{3}/{4}/{5}",
                protocol,
                port,
                string.IsNullOrWhiteSpace(appRoot)
                    ? string.Empty
                    : appRoot.TrimEnd('/') + '/',
                statefulServiceContext.PartitionId,
                statefulServiceContext.ReplicaId,
                Guid.NewGuid());
        }
        else if (serviceContext is StatelessServiceContext)
        {
            listeningAddress = string.Format(
                CultureInfo.InvariantCulture,
                "{0}://+:{1}/{2}",
                protocol,
                port,
                string.IsNullOrWhiteSpace(appRoot)
                    ? string.Empty
                    : appRoot.TrimEnd('/') + '/');
        }
        else
        {
            throw new InvalidOperationException();
        }

        publishAddress = listeningAddress.Replace("+", FabricRuntime.GetNodeContext().IPAddressOrFQDN);

        try
        {
            eventSource.Message("Starting web server on " + listeningAddress);
            webApp = WebApp.Start(listeningAddress, appBuilder => startup.Invoke(appBuilder));
            eventSource.Message("Listening on " + this.publishAddress);
            return Task.FromResult(this.publishAddress);
        }
        catch (Exception ex)
        {
            eventSource.Message("Web server failed to open endpoint {0}. {1}", this.endpointName, ex.ToString());
            StopWebServer();
            throw;
        }
    }

    public Task CloseAsync(CancellationToken cancellationToken)
    {
        this.eventSource.Message("Closing web server on endpoint {0}", this.endpointName);

        this.StopWebServer();

        return Task.FromResult(true);
    }

    public void Abort()
    {
        this.eventSource.Message("Aborting web server on endpoint {0}", this.endpointName);

        this.StopWebServer();
    }

    private void StopWebServer()
    {
        if (this.webApp != null)
        {
            try
            {
                this.webApp.Dispose();
            }
            catch (ObjectDisposedException)
            {
                // no-op
            }
        }
    }
}

And then finally I changed the CreateServiceInstanceListeners method in my stateless service code to:

protected override IEnumerable<ServiceInstanceListener> CreateServiceInstanceListeners()
    {
        return new[]
        {
            new ServiceInstanceListener(serviceContext => new OwinCommunicationListener(Startup.ConfigureApp, serviceContext, ServiceEventSource.Current, "ServiceEndpoint"))
        };
    }

回答2:

Create a Stateless service With Owin listener. Then in start up configure for signalR and backplane(service bus or sql). The issue ideally you would face is with a negotiate(Hand shake between Signalr client with server) At this point try configure for cross origin request, a sample code for persistent connection will look like below.

Also note the line appBuilder.UseAesDataProtectorProvider("Your Key") as it is important. The result of this is that you wont end up getting HTTP 400 to connect most of the time. This is because SignalR will make at least 2 requests at handshake and those will usually hit two different machines.

Thanks to marcin budny on the explanation.

var config = new HttpConfiguration();

// Configure your origins as required.

var cors = new EnableCorsAttribute("*", "*", "*");

config.EnableCors(cors);

FormatterConfig.ConfigureFormatters(config.Formatters);

RouteConfig.RegisterRoutes(config.Routes);

appBuilder.UseWebApi(config);

GlobalHost.DependencyResolver.UseServiceBus("yourconnection string comes here", "signalrbackplaneserver");
appBuilder.UseAesDataProtectorProvider("some password");
appBuilder.Map("/echo", map =>
{
                map.UseCors(CorsOptions.AllowAll).RunSignalR<MyEndPoint>();
});

来源：https://stackoverflow.com/questions/39649027/setup-signalr-and-service-bus-inside-a-azure-service-fabric-service