Make waiting for transport start optional. (#483)

src/Tingle.EventBus/DependencyInjection/EventBusOptions.cs

@@ -1,4 +1,5 @@
-using Polly.Retry;
+using Microsoft.Extensions.Hosting;
+using Polly.Retry;
 using System.Collections.Concurrent;
 using System.Diagnostics.CodeAnalysis;
 using Tingle.EventBus;
@@ -14,6 +15,14 @@ public class EventBusOptions
 {
     private readonly IList<EventBusTransportRegistrationBuilder> transports = new List<EventBusTransportRegistrationBuilder>();
 
+    /// <summary>
+    /// Whether to wait for the transport to be ready before publishing/cancelling events.
+    /// Set this to false when not using or starting an <see cref="IHost"/> because the bus and its transports
+    /// are started in an <see cref="IHostedService"/>.
+    /// Defaults to <see langword="true"/>.
+    /// </summary>
+    public bool WaitTransportStarted { get; set; } = true;
+
     /// <summary>
     /// Gets the <see cref="EventBusNamingOptions"/> for the Event Bus.
     /// </summary>

src/Tingle.EventBus/Transports/EventBusTransport.cs

@@ -119,6 +119,8 @@ public async Task StopAsync(CancellationToken cancellationToken)
 
     private Task WaitStartedAsync(CancellationToken cancellationToken)
     {
+        if (!BusOptions.WaitTransportStarted) return Task.CompletedTask;
+
         var tsk = startedTcs.Task;
         if (tsk.Status is TaskStatus.RanToCompletion) return tsk;
         return Task.Run(() => tsk, cancellationToken); // allows for cancellation by caller