Question

上下文：我有一些代码正在使用特定的会话创建消息会话 ISessionClient.Task<IMessageSession> AcceptMessageSessionAsync(string sessionId, TimeSpan operationTimeout);

问题：AcceptMessageSessionAsync中的operationTimeout有什么作用？我尝试将其设置为一分钟，但是片刻后什么也没有发生。此超时是否只是设置了我需要检查自己的属性？ SessionLockLostException是否不应该触发？

代码示例：

var session = await sessionClient.AcceptMessageSessionAsync(0, TimeSpan.FromMinutes(1));
var gotSession = true;

if (gotSession)
{
    while (!session.IsClosedOrClosing)
    {
        try
        {
            Message message = await session.ReceiveAsync(TimeSpan.FromMinutes(2));
            if (message != null)
            {
                await session.CompleteAsync(message.SystemProperties.LockToken);
            }
            else
            {
                await session.CloseAsync();
            }
        }
    }
}

Answer 1

AcceptMessageSessionAsync中的OperationTimeout是调用应等待获取下一个会话的时间。

您可以在这里找到AcceptMessageSessionAsync方法的完整实现

 /// <summary>
        /// Gets a particular session object identified by <paramref name="sessionId"/> that can be used to receive messages for that sessionId.
        /// </summary>
        /// <param name="sessionId">The sessionId present in all its messages.</param>
        /// <param name="operationTimeout">Amount of time for which the call should wait to fetch the next session.</param>
        /// <remarks>All plugins registered on <see cref="SessionClient"/> will be applied to each <see cref="MessageSession"/> that is accepted.
        /// Individual sessions can further register additional plugins.</remarks>
        public async Task<IMessageSession> AcceptMessageSessionAsync(string sessionId, TimeSpan operationTimeout)
        {
            this.ThrowIfClosed();

            MessagingEventSource.Log.AmqpSessionClientAcceptMessageSessionStart(
                this.ClientId,
                this.EntityPath,
                this.ReceiveMode,
                this.PrefetchCount,
                sessionId);

            bool isDiagnosticSourceEnabled = ServiceBusDiagnosticSource.IsEnabled();
            Activity activity = isDiagnosticSourceEnabled ? this.diagnosticSource.AcceptMessageSessionStart(sessionId) : null;
            Task acceptMessageSessionTask = null;

            var session = new MessageSession(
                this.EntityPath,
                this.EntityType,
                this.ReceiveMode,
                this.ServiceBusConnection,
                this.CbsTokenProvider,
                this.RetryPolicy,
                this.PrefetchCount,
                sessionId,
                true);

            try
            {
                acceptMessageSessionTask = this.RetryPolicy.RunOperation(
                    () => session.GetSessionReceiverLinkAsync(operationTimeout),
                    operationTimeout);
                await acceptMessageSessionTask.ConfigureAwait(false);
            }
            catch (Exception exception)
            {
                if (isDiagnosticSourceEnabled)
                {
                    this.diagnosticSource.ReportException(exception);
                }

                MessagingEventSource.Log.AmqpSessionClientAcceptMessageSessionException(
                    this.ClientId,
                    this.EntityPath,
                    exception);

                await session.CloseAsync().ConfigureAwait(false);
                throw AmqpExceptionHelper.GetClientException(exception);
            }
            finally
            {
                this.diagnosticSource.AcceptMessageSessionStop(activity, session.SessionId, acceptMessageSessionTask?.Status);
            }

            MessagingEventSource.Log.AmqpSessionClientAcceptMessageSessionStop(
                this.ClientId,
                this.EntityPath,
                session.SessionIdInternal);

            session.UpdateClientId(ClientEntity.GenerateClientId(nameof(MessageSession), $"{this.EntityPath}_{session.SessionId}"));
            // Register plugins on the message session.
            foreach (var serviceBusPlugin in this.RegisteredPlugins)
            {
                session.RegisterPlugin(serviceBusPlugin);
            }

            return session;
        }

您可以在下面的链接中找到完整的示例

https://github.com/Azure/azure-service-bus-dotnet/blob/dev/src/Microsoft.Azure.ServiceBus/SessionClient.cs

希望有帮助。

ISessionClient.AcceptMessageSessionAsync中的operationTimeout实际做什么？

1 个答案: