Question

我正在使用MassTransit（使用RabbitMQ）和Automatonymous开发一个传奇。我使用EntityFramework作为我的商店引擎，MySQL作为我的数据库。每当我尝试运行saga并将其状态存储在数据库中时，EF和MySQL的组合就会抛出异常。使用this示例应用程序并使用连接字符串到MySQL数据库可以重现该问题。引发的确切异常是：

System.Data.SqlClient.SqlException（0x80131904）：与网络相关或建立连接时发生特定于实例的错误 SQL Server。服务器未找到或无法访问。 Ve rify 实例名称正确且SQL Server配置为允许远程连接。（提供者：命名管道提供商，错误：40 - 无法打开与SQL Server的连接）---＆gt; SYSTE m.ComponentModel.Win32Exception（0x80004005）：系统找不到指定的文件 System.Data.SqlClient.SqlInternalConnectionTds..ctor（DbConnectionPoolIdentity identity，SqlConnectionString connectionOptions，SqlCredential 凭证，Object providerInfo，String newPassword，SecureString newSecurePassword，Boolean redirectedUserInstance，SqlConnectionString userConnectionOptions，SessionData reconnectSessionData， DbConnectionPool池，String accessToken，Boolean applyTra nsientFaultHandling）at System.Data.SqlClient.SqlConnectionFactory.CreateConnection（DbConnectionOptions options，DbConnectionPoolKey poolKey，Object poolGroupProviderInfo， DbConnectionPool池，DbConnection拥有连接， DbConnectionOptions userOptions）at System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection（类DBConnectionPool pool，DbConnection owningObject，DbConnectionOptions选项， DbConnectionPoolKey poolKey，DbConnectionOption的userOptions）at System.Data.ProviderBase.DbConnectionPool.CreateObject（的DbConnection owningObject，DbConnectionOptions userOptions，DbConnectionInternal oldConnection） System.Data.ProviderBase.DbConnectionPool.UserCreateRequest（的DbConnection owningObject，DbConnectionOptions userOptions，DbConnectionInternal oldConnection） System.Data.ProviderBase.DbConnectionPool.TryGetConnection（的DbConnection owningObject，UInt32 waitForMultipleObjectsTimeout，Boolean allowCreate，Boolean onlyOneCheckConnection，DbConnectionOptio ns userOptions，DbConnectionInternal＆amp;连接） System.Data.ProviderBase.DbConnectionPool.TryGetConnection（的DbConnection owningObject，TaskCompletionSource 1 retry, DbConnectionOptions userOptions, DbConnectionInternal& connection) at System.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource 1重试，DbConnectionOptions userOptions，DbConnectionInternal oldConnection，Db ConnectionInternal＆安培;连接） System.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal（的DbConnection outerConnection，DbConnectionFactory connectionFactory， TaskCompletionSource 1 retry, DbConnectionOptions use rOptions) at System.Data.ProviderBase.DbConnectionClosed.TryOpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource 1重试，DbConnectionOptions userOptions）at System.Data.SqlClient.SqlConnection.TryOpenInner（TaskCompletionSource 1 retry) at System.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource 1 重试）在System.Data.SqlClient.SqlConnection.Open（）处 System.Data.Entity.Infrastructure.Interception.DbConnectionDispatcher.b__36（的DbConnection t，DbConnectionInterceptionContext c）at System.Data.Entity.Infrastructure.Interception.InternalDispatcher 1.Dispatch[TTarget,TInterceptionContext](TTarget target, Action 2操作，TInterceptionContext interceptionContext，行动3 executing, Action 3已执行） System.Data.Entity.Infrastructure.Interception.DbConnectionDispatcher.Open（的DbConnection connection，DbInterceptionContext interceptionContext）at System.Data.Entity.SqlServer.SqlProviderServices＆LT;＆GT; c__DisplayClass33.b__32（）在 System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy＆LT;＆GT; c__DisplayClass1.b__0（）在 System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute [TResult]（Func 1 operation) at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute(Action operation) at System.Data.Entity.SqlServer.SqlProviderServices.UsingConnection(DbConnection sqlConnection, Action 1 act）at at System.Data.Entity.SqlServer.SqlProviderServices.UsingMasterConnection（的DbConnection sqlConnection，Action 1 act) at System.Data.Entity.SqlServer.SqlProviderServices.CreateDatabaseFromScript(Nullable 1 commandTimeout，DbConnection sqlConnection，String createDatabaseScript）at System.Data.Entity.SqlServer.SqlProviderServices.DbCreateDatabase（的DbConnection connection，Nullable 1 commandTimeout, StoreItemCollection storeItemCollection) at System.Data.Entity.Core.Common.DbProviderServices.CreateDatabase(DbConnection connection, Nullable 1 commandTimeout，StoreItemCollection storeItemCollection）at System.Data.Entity.Core.Objects.ObjectContext.CreateDatabase（）at System.Data.Entity.Migrations.Utilities.DatabaseCreator.Create（的DbConnection 连接） System.Data.Entity.Migrations.DbMigrator.EnsureDatabaseExists（动作 mustSucceedToKeepDatabase）at System.Data.Entity.Migrations.DbMigrator.Update（字符串 targetMigration） System.Data.Entity.Internal.DatabaseCreator.CreateDatabase（InternalContext internalContext，Func 3 createMigrator, ObjectContext objectContext) at System.Data.Entity.Internal.InternalContext.CreateDatabase(ObjectContext objectContext, DatabaseExistenceState existenceState) at System.Data.Entity.Database.Create(DatabaseExistenceState existenceState) at System.Data.Entity.CreateDatabaseIfNotExists 1.InitializeDatabase（TContext 上下文） System.Data.Entity.Internal.InternalContext＆LT;＆GT; c__DisplayClassf 1.<CreateInitializationAction>b__e() at System.Data.Entity.Internal.InternalContext.PerformInitializationAction(Action action) at System.Data.Entity.Internal.InternalContext.PerformDatabaseInitialization() at System.Data.Entity.Internal.LazyInternalContext.<InitializeDatabase>b__4(InternalContext c) at System.Data.Entity.Internal.RetryAction 1.PerformAction（TInput 输入） System.Data.Entity.Internal.LazyInternalContext.InitializeDatabaseAction（动作1 action) at System.Data.Entity.Internal.LazyInternalContext.InitializeDatabase() at System.Data.Entity.Internal.LazyInternalContext.get_ObjectContext() at System.Data.Entity.Database.BeginTransaction(IsolationLevel isolationLevel) at MassTransit.EntityFrameworkIntegration.Saga.EntityFrameworkSagaRepository {1.d__8 {1}} 2.＆GT; - 发送＆GT; d__6.MoveNext（） ---从抛出异常的先前位置开始的堆栈跟踪结束--- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw（）at MassTransit.Saga.Pipeline.Filters.QuerySagaFilter 1.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at System.Runtime.CompilerServices.TaskAwaiter.GetResult() at MassTransit.Saga.Pipeline.Filters.QuerySagaFilter 1.d__3.MoveNext（） ---从抛出异常的先前位置开始的堆栈跟踪结束--- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess（任务任务） System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification（任务任务）在System.Runtime.CompilerServices.TaskAwaiter.GetResult（）at MassTransit.Pipeline.Filters.TeeConsumeFilter 2.<MassTransit-Pipeline-IFilter<MassTransit-ConsumeContext<TMessage>>-Send>d__6.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at System.Runtime.CompilerServices.TaskAwaiter.GetResult() at MassTransit.Saga.Pipeline.Filters.CorrelationIdMessageFilter 1.d__7.MoveNext（） ---从抛出异常的先前位置开始的堆栈跟踪结束--- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess（任务任务） System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification（任务任务）在System.Runtime.CompilerServices.TaskAwaiter.GetResult（）at MassTransit.Pipeline.Filters.MessageConsumeFilter 1.<>c__DisplayClass7_0.<<Send>b__0>d.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at System.Runtime.CompilerServices.TaskAwaiter.GetResult() at MassTransit.Pipeline.Filters.TeeConsumeFilter 1-SEND＆GT; d__7.MoveNext（） ---从抛出异常的先前位置开始的堆栈跟踪结束--- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess（任务任务） System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification（任务任务）在System.Runtime.CompilerServices.TaskAwaiter.GetResult（）at MassTransit.Pipeline.Filters.DeserializeFilter.d__4.MoveNext（） ---从抛出异常的先前位置开始的堆栈跟踪结束--- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess（任务任务） System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification（任务任务）在System.Runtime.CompilerServices.TaskAwaiter.GetResult（）at MassTransit.Pipeline.Filters.RescueReceiveContextFilter`1.-SEND＆GT; d__5.MoveNext（） ClientConnectionId：00000000-0000-0000-0000-000000000000错误号：2，状态：0，类别：20

如果我使用VS 2015安装的本地数据库而不是MySQL，那么它的工作原理非常好。它也适用于内存存储。即使异常说无法找到服务器，我也可以确认它是否存在且可以访问，因为示例应用程序在选择连接字符串时首先进行检查并且成功：

1.<MassTransit-Pipeline-IFilter<MassTransit-ConsumeContext>-Send>d__7.MoveNext()
  --- End of stack trace from previous location where exception was thrown ---  at
  System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()  at
  MassTransit.Pipeline.Filters.MessageConsumeFilter

问题可能是因为它试图用SqlClient访问MySQL数据库吗？

我使用的是MySQL Server 5.7，EF 6.1.3，MassTransit 3.5.7和Automatonymous 3.5.11。

Answer 1

这不是MassTransit问题，而是实体框架问题。应该是这样的：

如何在MySQL中使用Entity Framework。

你的例外清楚地说：System.Data.SqlClient正在抛弃它。这是SQL Server客户端。它还说：

无法打开与SQL Server的连接

您可以参考documentation了解如何配置EF和MySQL。通常，您需要安装MySql.Data.Entity NuGet包并告诉EF您正在使用MySQL，然后配置正确的连接字符串：

<connectionStrings>
    <add name="MyContext" providerName="MySql.Data.MySqlClient"
        connectionString="server=localhost;port=3306;database=mycontext;uid=root;password=********"/>
</connectionStrings>
<entityFramework>
    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework"/>
    <providers>
        <provider invariantName="MySql.Data.MySqlClient"
            type="MySql.Data.MySqlClient.MySqlProviderServices, MySql.Data.Entity.EF6"/>
        <provider invariantName="System.Data.SqlClient"
            type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer"/>
    </providers>
</entityFramework>

使用实体框架和MySQL

1 个答案: