EventLoop.cs
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33 
34 using System;
35 using System.Collections.Generic;
36 using System.Linq;
37 using System.Text;
38 using System.Threading;
39 using System.Threading.Tasks;
40 
41 namespace Microsoft.Bot.Builder.Base
42 {
43  public interface IEventLoop
44  {
50  Task PollAsync(CancellationToken token);
51  }
52 
53  public interface IEventProducer<in Event>
54  {
55  void Post(Event @event, Action onPull = null);
56  }
57 
58  public interface IEventConsumer<Event>
59  {
60  bool TryPull(out Event @event);
61  }
62 
63  public sealed class EventQueue<Event> : IEventProducer<Event>, IEventConsumer<Event>
64  {
65  private struct Item
66  {
67  public Event Event { get; set; }
68  public Action OnPull { get; set; }
69  }
70 
71  private readonly Queue<Item> queue = new Queue<Item>();
72  void IEventProducer<Event>.Post(Event @event, Action onPull)
73  {
74  var item = new Item() { Event = @event, OnPull = onPull };
75  this.queue.Enqueue(item);
76  }
77 
78  bool IEventConsumer<Event>.TryPull(out Event @event)
79  {
80  if (queue.Count > 0)
81  {
82  var item = this.queue.Dequeue();
83  @event = item.Event;
84  var onPull = item.OnPull;
85  onPull?.Invoke();
86 
87  return true;
88  }
89  else
90  {
91  @event = default(Event);
92  return false;
93  }
94  }
95  }
96 }
void Post(Event @event, Action onPull=null)