C# 从生产者/消费者队列中删除已取消的任务
我想使用异步生产者/消费者队列(AsyncEx-lib)通过总线一次发送一条消息。现在,我只是通过异步阻塞来实现这一点。工作正常,但我无法控制队列:( 所以我提出了以下解决方案,问题是取消的任务没有从队列中移除。如果我将队列限制为10(因为每个消息发送需要1s,最大队列时间应该是10s左右)队列已经包含8个等待任务和2个取消的任务,下一个排队的任务将抛出InvalidOperationException,尽管这两个取消的任务不会被发送 也许有更好的方法:DC# 从生产者/消费者队列中删除已取消的任务,c#,async-await,producer-consumer,C#,Async Await,Producer Consumer,我想使用异步生产者/消费者队列(AsyncEx-lib)通过总线一次发送一条消息。现在,我只是通过异步阻塞来实现这一点。工作正常,但我无法控制队列:( 所以我提出了以下解决方案,问题是取消的任务没有从队列中移除。如果我将队列限制为10(因为每个消息发送需要1s,最大队列时间应该是10s左右)队列已经包含8个等待任务和2个取消的任务,下一个排队的任务将抛出InvalidOperationException,尽管这两个取消的任务不会被发送 也许有更好的方法:D class Program {
class Program
{
static AsyncProducerConsumerQueue<Tuple<string, TaskCompletionSource>> s_Queue =
new AsyncProducerConsumerQueue<Tuple<string, TaskCompletionSource>>();
static void Main()
{
StartAsync().Wait();
}
static async Task StartAsync()
{
var sendingTask = StartSendingAsync();
var tasks = new List<Task>();
using (var cts = new CancellationTokenSource(TimeSpan.FromSeconds(8)))
{
for (var i = 0; i < 10; i++)
{
tasks.Add(EnqueueMessageAsync("Message " + i, cts.Token));
}
try
{
await Task.WhenAll(tasks);
Console.WriteLine("All messages sent.");
}
catch (TaskCanceledException)
{
Console.WriteLine("At least one task was canceled.");
}
}
s_Queue.CompleteAdding();
await sendingTask;
s_Queue.Dispose();
Console.WriteLine("Queue completed.");
Console.WriteLine("Press any key to continue...");
Console.ReadKey();
}
static async Task EnqueueMessageAsync(string message, CancellationToken token)
{
var tcs = new TaskCompletionSource();
using (token.Register(() => tcs.TrySetCanceled()))
{
await s_Queue.EnqueueAsync(new Tuple<string, TaskCompletionSource>(message, tcs));
Console.WriteLine("Thread '{0}' - {1}: {2} queued.", Thread.CurrentThread.ManagedThreadId, DateTime.Now.TimeOfDay, message);
await tcs.Task;
}
}
static async Task SendMessageAsync(string message)
{
await Task.Delay(TimeSpan.FromSeconds(1));
Console.WriteLine("Thread '{0}' - {1}: {2} sent.", Thread.CurrentThread.ManagedThreadId, DateTime.Now.TimeOfDay, message);
}
static async Task StartSendingAsync()
{
while (await s_Queue.OutputAvailableAsync())
{
var t = await s_Queue.DequeueAsync();
if (t.Item2.Task.IsCanceled || t.Item2.Task.IsFaulted) continue;
await SendMessageAsync(t.Item1);
t.Item2.TrySetResult();
}
}
}
类程序
{
静态AsyncProducerConsumerQueue s\u队列=
新建AsyncProducerConsumerQueue();
静态void Main()
{
StartAsync().Wait();
}
静态异步任务StartAsync()
{
var sendingTask=StartSendingAsync();
var tasks=新列表();
使用(var cts=new CancellationTokenSource(TimeSpan.FromSeconds(8)))
{
对于(变量i=0;i<10;i++)
{
添加(EnqueueMessageAsync(“Message”+i,cts.Token));
}
尝试
{
等待任务。何时(任务);
Console.WriteLine(“已发送的所有消息”);
}
捕获(TaskCanceledException)
{
Console.WriteLine(“至少有一个任务被取消。”);
}
}
s_Queue.CompleteAdding();
等待发送任务;
s_Queue.Dispose();
Console.WriteLine(“队列已完成”);
Console.WriteLine(“按任意键继续…”);
Console.ReadKey();
}
静态异步任务EnqueueMessageAsync(字符串消息、CancellationToken令牌)
{
var tcs=new TaskCompletionSource();
使用(token.Register(()=>tcs.TrySetCanceled())
{
等待s_Queue.EnqueueAsync(新元组(消息,tcs));
WriteLine(“线程'{0}'-{1}:{2}排队。”,Thread.CurrentThread.ManagedThreadId,DateTime.Now.TimeOfDay,message);
等待tcs任务;
}
}
静态异步任务SendMessageAsync(字符串消息)
{
等待任务延迟(时间跨度从秒(1));
WriteLine(“线程{0}-{1}:{2}已发送。”,Thread.CurrentThread.ManagedThreadId,DateTime.Now.TimeOfDay,message);
}
静态异步任务StartSendingSync()
{
while(等待s_Queue.OutputAvailableAsync())
{
var t=wait s_Queue.DequeueAsync();
如果(t.Item2.Task.IsCanceled | | t.Item2.Task.IsFaulted)继续;
等待SendMessageAsync(t.Item1);
t、 第2项TrySetResult();
}
}
}
编辑1:
正如svik所指出的,只有当队列已经完成时才会抛出InvalidOperationException。因此,此解决方案甚至无法解决我最初遇到的等待任务的非托管“队列”问题。例如,如果有10次以上的呼叫/10次,我会得到一个完整的队列和一个额外的非托管“队列”许多等待的任务,比如我的异步阻塞方法(AsyncMonitor)。我想我必须想出一些其他的解决方案,然后
编辑2:
我有N个不同的消息生产者(我不知道有多少,因为这不是我的代码),只有一个消费者通过总线发送消息并检查它们是否正确发送(不是真正的字符串消息)
以下代码模拟代码应该中断的情况(队列大小为10):
using (var cts = new CancellationTokenSource(TimeSpan.FromSeconds(5)))
{
for (var i = 0; i < 10; i++) { tasks.Add(EnqueueMessageAsync("Message " + i, cts.Token)); }
await Task.Delay(TimeSpan.FromSeconds(5));
for (var i = 10; i < 21; i++) { tasks.Add(EnqueueMessageAsync("Message " + i, default(CancellationToken))); }
try
{
await Task.WhenAll(tasks);
Console.WriteLine("All messages sent.");
}
catch (TaskCanceledException)
{
Console.WriteLine("At least one task was canceled.");
Console.WriteLine("Press any key to complete queue...");
Console.ReadKey();
}
}
使用(var cts=new CancellationTokenSource(TimeSpan.FromSeconds(5)))
{
对于(var i=0;i<10;i++){tasks.Add(EnqueueMessageAsync(“Message”+i,cts.Token));}
等待任务延迟(时间跨度从秒(5));
对于(var i=10;i<21;i++){tasks.Add(EnqueueMessageAsync(“Message”+i,default(CancellationToken));}
尝试
{
等待任务。何时(任务);
Console.WriteLine(“已发送的所有消息”);
}
捕获(TaskCanceledException)
{
Console.WriteLine(“至少有一个任务被取消。”);
Console.WriteLine(“按任意键完成队列…”);
Console.ReadKey();
}
}
目标是,我想完全控制所有应该发送的消息,但在我之前发布的代码中并非如此,因为我只能控制队列中的消息,而不能控制等待排队的消息(可能有10000条消息在异步等待排队,我不知道=>生产者代码是否会像预期的那样工作,因为发送所有正在等待的消息将花费永远的时间…)
我希望这能让我更清楚地知道我想要实现什么;)我不确定回答我自己的问题是否合适,所以我不会把它标记为答案,也许有人会想出一个更好的解决方案:p 首先,这里是生产商代码:
static async Task StartAsync()
{
using (var queue = new SendMessageQueue(10, new SendMessageService()))
using (var timeoutTokenSource = new CancellationTokenSource(TimeSpan.FromSeconds(4.5)))
{
var tasks = new List<Task>();
for (var i = 0; i < 10; i++)
{
tasks.Add(queue.SendAsync(i.ToString(), timeoutTokenSource.Token));
}
await Task.Delay(TimeSpan.FromSeconds(4.5));
for (var i = 10; i < 25; i++)
{
tasks.Add(queue.SendAsync(i.ToString(), default(CancellationToken)));
}
await queue.CompleteSendingAsync();
for (var i = 0; i < tasks.Count; i++ )
{
try
{
await tasks[i];
Console.WriteLine("Message '{0}' send.", i);
}
catch (TaskCanceledException)
{
Console.WriteLine("Message '{0}' canceled.", i);
}
catch (QueueOverflowException ex)
{
Console.WriteLine(ex.Message);
}
}
}
Console.WriteLine("Press any key to continue...");
Console.ReadKey();
}
静态异步任务StartAsync()
{
使用(var queue=new SendMessageQueue(10,new SendMessageService()))
使用(var timeoutTokenSource=new CancellationTokenSource(TimeSpan.FromSeconds(4.5)))
{
var tasks=新列表();
对于(变量i=0;i<10;i++)
{
添加(queue.sendsync(i.ToString(),timeoutTokenSource.Token));
}
等待任务延迟(时间跨度从秒(4.5));
对于(变量i=10;i<25;i++)
{
tasks.Add(queue.SendAsync(i.ToSt
class SendMessageQueue : IDisposable
{
private bool m_Disposed;
private bool m_CompleteSending;
private Task m_SendingTask;
private AsyncMonitor m_Monitor;
private List<MessageTaskCompletionSource> m_MessageCollection;
private ISendMessageService m_SendMessageService;
public int Capacity { get; private set; }
public SendMessageQueue(int capacity, ISendMessageService service)
{
Capacity = capacity;
m_Monitor = new AsyncMonitor();
m_MessageCollection = new List<MessageTaskCompletionSource>();
m_SendMessageService = service;
m_SendingTask = StartSendingAsync();
}
public async Task<bool> SendAsync(string message, CancellationToken token)
{
if (m_Disposed) { throw new ObjectDisposedException(GetType().Name); }
if (message == null) { throw new ArgumentNullException("message"); }
using (var messageTcs = new MessageTaskCompletionSource(message, token))
{
await AddAsync(messageTcs);
return await messageTcs.Task;
}
}
public async Task CompleteSendingAsync()
{
if (m_Disposed) { throw new ObjectDisposedException(GetType().Name); }
using (m_Monitor.Enter())
{
m_CompleteSending = true;
}
await m_SendingTask;
}
private async Task AddAsync(MessageTaskCompletionSource message)
{
using (await m_Monitor.EnterAsync(message.Token))
{
if (m_CompleteSending) { throw new InvalidOperationException("Queue already completed."); }
if (Capacity < m_MessageCollection.Count)
{
m_MessageCollection.RemoveAll(item => item.IsCanceled);
if (Capacity < m_MessageCollection.Count)
{
throw new QueueOverflowException(string.Format("Queue overflow; '{0}' couldn't be enqueued.", message.Message));
}
}
m_MessageCollection.Add(message);
}
m_Monitor.Pulse(); // signal new message
Console.WriteLine("Thread '{0}' - {1}: '{2}' enqueued.", Thread.CurrentThread.ManagedThreadId, DateTime.Now.TimeOfDay, message.Message);
}
private async Task<MessageTaskCompletionSource> TakeAsync()
{
using (await m_Monitor.EnterAsync())
{
var message = m_MessageCollection.ElementAt(0);
m_MessageCollection.RemoveAt(0);
return message;
}
}
private async Task<bool> OutputAvailableAsync()
{
using (await m_Monitor.EnterAsync())
{
if (m_MessageCollection.Count > 0) { return true; }
else if (m_CompleteSending) { return false; }
await m_Monitor.WaitAsync();
return true;
}
}
private async Task StartSendingAsync()
{
while (await OutputAvailableAsync())
{
var message = await TakeAsync();
if (message.IsCanceled) continue;
try
{
var result = await m_SendMessageService.SendMessageAsync(message.Message, message.Token);
message.TrySetResult(result);
}
catch (TaskCanceledException) { message.TrySetCanceled(); }
}
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
protected void Dispose(bool disposing)
{
if (m_Disposed) return;
if (disposing)
{
if (m_MessageCollection != null)
{
var tmp = m_MessageCollection;
m_MessageCollection = null;
tmp.ForEach(item => item.Dispose());
tmp.Clear();
}
}
m_Disposed = true;
}
#region MessageTaskCompletionSource Class
class MessageTaskCompletionSource : TaskCompletionSource<bool>, IDisposable
{
private bool m_Disposed;
private IDisposable m_CancellationTokenRegistration;
public string Message { get; private set; }
public CancellationToken Token { get; private set; }
public bool IsCompleted { get { return Task.IsCompleted; } }
public bool IsCanceled { get { return Task.IsCanceled; } }
public bool IsFaulted { get { return Task.IsFaulted; } }
public MessageTaskCompletionSource(string message, CancellationToken token)
{
m_CancellationTokenRegistration = token.Register(() => TrySetCanceled());
Message = message;
Token = token;
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
protected void Dispose(bool disposing)
{
if (m_Disposed) return;
if (disposing)
{
TrySetException(new ObjectDisposedException(GetType().Name));
if (m_CancellationTokenRegistration != null)
{
var tmp = m_CancellationTokenRegistration;
m_CancellationTokenRegistration = null;
tmp.Dispose();
}
}
m_Disposed = true;
}
}
#endregion
}