/// <summary>
/// Uses a <see cref="QueueCursor"/> to look for messages with a matching <paramref name="correlationId"/>
/// Returns the matching message or NULL if no matching message can be found with the allowed <paramref name="timeout"/>.
/// </summary>
public static async Task <Message> ReadByCorrelationIdAsync(this QueueReader queue, MessageId correlationId, Properties properties = Properties.All, TimeSpan?timeout = null, QueueTransaction transaction = null)
{
timeout = timeout ?? QueueReader.Infinite;
var start = DateTime.UtcNow;
using (var cur = new QueueCursor(queue))
{
var msg = await cur.PeekAsync(Properties.CorrelationId | Properties.LookupId, timeout);
for (;;)
{
if (msg == null)
{
return(null);
}
if (msg.CorrelationId == correlationId)
{
return(queue.Lookup(properties, msg.LookupId, LookupAction.ReceiveCurrent, TimeSpan.Zero, transaction));
}
var elapsed = DateTime.UtcNow - start;
var remaining = timeout - elapsed;
if (remaining <= TimeSpan.Zero)
{
return(null);
}
msg = await cur.PeekNextAsync(Properties.CorrelationId | Properties.LookupId, remaining);
}
}
}
/// <summary>Peeks at all the messages currently in the queue using a <see cref="QueueCursor"/></summary>
public IEnumerator <Message> GetEnumerator()
{
using (var c = new QueueCursor(this))
{
for (var msg = c.Peek(timeout:TimeSpan.Zero); msg != null; msg = c.PeekNext(timeout: TimeSpan.Zero))
{
yield return(msg);
}
}
}
