EasyNetQ (AMQP) Single Application Connection In ASP.NET? - asp.net

Question

Community:
I'm struggling to figure out how to create a single AMQP connection that lives with my ASP.NET application lifecycle in ASP.NET using .NET Core 2.1. After researching, I've found lots of references to using a single AMQP connection for the whole application as they are expensive and slow to create and I was headed down the road of creating the connection using DI but it appears my approach is flawed, I can't seem to identify which interface I need to add as a singleton...
public void ConfigureServices(IServiceCollection services)
{
var sqlConnectionStringBuilder = new SqlConnectionStringBuilder(Configuration.GetConnectionString("DefaultConnection"));
var envSQL = Environment.GetEnvironmentVariable("ASPNETCORE_SQL_SERVER");
if (envSQL != null)
sqlConnectionStringBuilder.DataSource = envSQL;
services.AddSingleton<IMessageBusService, MessageBusService>();
services.AddSingleton<EasyNetQ.IAdvancedBus, RabbitAdvancedBus>();
services.AddSingleton<EasyNetQ.IConnectionFactory, ConnectionFactoryWrapper>();
services.AddMvc();
}
Adding the above interfaces works but I get an error about ConnectionConfiguration service not being locatable. Is this the right direction or is there a more proper way to create a single application once EasyNetQ connection in ASP.NET core?

Answer 1

You can use AutoSubcriber in .net core
and use the sample code here.
add connection to appsettings.json
"MessageBroker": {
"ConnectionString": "host=localhost"
}
then add IBus in ConfigureServices
public void ConfigureServices(IServiceCollection services)
{
services.AddSingleton<IBus>(RabbitHutch.CreateBus(Configuration["MessageBroker:ConnectionString"]));
services.AddSingleton(RabbitHutch.CreateBus(Configuration["MessageBroker:ConnectionString"]));
services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_2);
}
add class AppBuilderExtension and use extension method for auto subscriber
public static class AppBuilderExtension
{
public static IApplicationBuilder UseSubscribe(this IApplicationBuilder appBuilder, string subscriptionIdPrefix, Assembly assembly)
{
var services = appBuilder.ApplicationServices.CreateScope().ServiceProvider;
var lifeTime = services.GetService<IApplicationLifetime>();
var Bus = services.GetService<IBus>();
lifeTime.ApplicationStarted.Register(() =>
{
var subscriber = new AutoSubscriber(Bus, subscriptionIdPrefix);
subscriber.Subscribe(assembly);
subscriber.SubscribeAsync(assembly);
});
lifeTime.ApplicationStopped.Register(() => Bus.Dispose());
return appBuilder;
}
}
add UseSubscribe in Configure
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
else
{
app.UseHsts();
}
app.UseSubscribe("ClientMessageService", Assembly.GetExecutingAssembly());
app.UseHttpsRedirection();
app.UseMvc();
}
then create Producers controller
[Route("api/[controller]")]
[ApiController]
public class ProducersController : ControllerBase
{
private readonly IBus _bus;
public ProducersController(IBus bus)
{
_bus = bus;
}
[HttpGet]
[Route("Send")]
public JsonResult Send()
{
_bus.Publish(new TextMessage { Text = "Send Message from the Producer" });
return new JsonResult("");
}
}
then create Consumers controller
[Route("api/[controller]")]
[ApiController]
public class ConsumersController : ControllerBase, IConsume<TextMessage>
{
[HttpGet]
[Route("Receive")]
public JsonResult Receive()
{
using (var bus = RabbitHutch.CreateBus("host=localhost"))
{
bus.Subscribe<TextMessage>("test", HandleTextMessage);
}
return new JsonResult("");
}
private static void HandleTextMessage(TextMessage textMessage)
{
var item = textMessage.Text;
}
public void Consume(TextMessage message)
{
// code receive message
}
}