/// <summary>
/// A convenience method to get a message as <see cref="TMessage"/> from the context.
/// </summary>
/// <param name="context">The context to get the message from.</param>
/// <typeparam name="TMessage">The type of the message to try and get from the context.</typeparam>
/// <returns>An instance of <see cref="TMessage"/> or null if the message was not of type <see cref="TMessage"/></returns>
/// <exception cref="ArgumentNullException">The <see cref="context"/> object is null.</exception>
public static TMessage MessageAs <TMessage>(this HandleMessageContext context) where TMessage : Message
{
if (context == null)
{
throw new ArgumentNullException(nameof(context));
}
return(context.Message as TMessage);
}
protected override async Task <bool> RunInnerAsync(HandleMessageContext context, Func <CancellationToken, Task <bool> > func, CancellationToken stoppingToken)
{
if (context == null)
{
throw new ArgumentNullException(nameof(context));
}
if (func == null)
{
throw new ArgumentNullException(nameof(func));
}
string lockKey = $"{context.Message.UniqueKey()}-{_lockSuffixKeyForHandler}";
MessageLockResponse lockResponse = await _messageLock.TryAcquireLockAsync(lockKey, _timeout).ConfigureAwait(false);
if (!lockResponse.DoIHaveExclusiveLock)
{
if (lockResponse.IsMessagePermanentlyLocked)
{
_logger.LogDebug("Failed to acquire lock for message with key {MessageLockKey} as it is permanently locked.", lockKey);
return(RemoveTheMessageFromTheQueue);
}
_logger.LogDebug("Failed to acquire lock for message with key {MessageLockKey}; returning message to queue.", lockKey);
return(LeaveItInTheQueue);
}
try
{
_logger.LogDebug("Acquired lock for message with key {MessageLockKey}.", lockKey);
bool successfullyHandled = await func(stoppingToken).ConfigureAwait(false);
if (successfullyHandled)
{
await _messageLock.TryAcquireLockPermanentlyAsync(lockKey).ConfigureAwait(false);
_logger.LogDebug("Acquired permanent lock for message with key {MessageLockKey}.", lockKey);
}
return(successfullyHandled);
}
catch (Exception)
{
await _messageLock.ReleaseLockAsync(lockKey).ConfigureAwait(false);
_logger.LogDebug("Released lock for message with key {MessageLockKey}.", lockKey);
throw;
}
}
protected override async Task <bool> RunInnerAsync(
HandleMessageContext context,
Func <CancellationToken, Task <bool> > func,
CancellationToken stoppingToken)
{
if (context == null)
{
throw new ArgumentNullException(nameof(context));
}
stoppingToken.ThrowIfCancellationRequested();
var resolutionContext = new HandlerResolutionContext(context.QueueName);
IHandlerAsync <T> handler = _handlerResolver(resolutionContext);
return(await handler.Handle(context.MessageAs <T>()).ConfigureAwait(false));
}