MassTransit传奇坚持与实体框架和MySQL

Question

我正在开发使用MassTransit（与RabbitMQ）和自动匿名的传奇。我使用EntityFramework作为我的商店引擎和MySQL作为我的数据库。每次我尝试运行传奇并将其状态存储在数据库中时，EF和MySQL的组合都会引发异常。使用this示例应用程序并使用连接字符串连接到MySQL数据库，可以重现问题。引发的确切例外是：

System.Data.SqlClient.SqlException (0x80131904): A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Ve rify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server) ---> Syste m.ComponentModel.Win32Exception (0x80004005): The system cannot find the file specified at System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, SqlCredential credential, Object providerInfo, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance, SqlConnectionString userConnectionOptions, SessionData reconnectSessionData, DbConnectionPool pool, String accessToken, Boolean applyTra nsientFaultHandling) at System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, DbConnectionPoolKey poolKey, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConn ection, DbConnectionOptions userOptions) at System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnectionPool pool, DbConnection owningObject, DbConnectionOptions options, DbConnectionPoolKey poolKey, DbConnectionOption s userOptions) at System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection) at System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection) at System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, UInt32 waitForMultipleObjectsTimeout, Boolean allowCreate, Boolean onlyOneCheckConnection, DbConnectionOptio ns userOptions, DbConnectionInternal& connection) at System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, TaskCompletionSource 1 retry, DbConnectionOptions userOptions, DbConnectionInternal& connection) at System.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource 1 retry, DbConnectionOptions userOptions, DbConnectionInternal oldConnection, Db ConnectionInternal& connection) at System.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource 1 retry, DbConnectionOptions use rOptions) at System.Data.ProviderBase.DbConnectionClosed.TryOpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource 1 retry, DbConnectionOptions userOptions) at System.Data.SqlClient.SqlConnection.TryOpenInner(TaskCompletionSource 1 retry) at System.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource 1 retry) at System.Data.SqlClient.SqlConnection.Open() at System.Data.Entity.Infrastructure.Interception.DbConnectionDispatcher.b__36(DbConnection t, DbConnectionInterceptionContext c) at System.Data.Entity.Infrastructure.Interception.InternalDispatcher 1.Dispatch[TTarget,TInterceptionContext](TTarget target, Action 2 operation, TInterceptionContext interceptionContext, Action 3 executing, Action 3 executed) at System.Data.Entity.Infrastructure.Interception.DbConnectionDispatcher.Open(DbConnection connection, DbInterceptionContext interceptionContext) at System.Data.Entity.SqlServer.SqlProviderServices.<>c__DisplayClass33.b__32() at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.<>c__DisplayClass1.b__0() at 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 System.Data.Entity.SqlServer.SqlProviderServices.UsingMasterConnection(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(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(DbConnection connection) at System.Data.Entity.Migrations.DbMigrator.EnsureDatabaseExists(Action mustSucceedToKeepDatabase) at System.Data.Entity.Migrations.DbMigrator.Update(String targetMigration) at 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 context) at System.Data.Entity.Internal.InternalContext.<>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 input) at System.Data.Entity.Internal.LazyInternalContext.InitializeDatabaseAction(Action 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.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 2.>-Send>d__6.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at MassTransit.Saga.Pipeline.Filters.QuerySagaFilter 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__3.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.<>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.d__7.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.MessageConsumeFilter 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 1.-Send>d__7.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.DeserializeFilter.d__4.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.RescueReceiveContextFilter`1.-Send>d__5.MoveNext() ClientConnectionId:00000000-0000-0000-0000-000000000000 Error Number:2,State:0,Class:20

如果我使用本地数据库与VS 2015而不是MySQL安装，那么它工作得很好。它也适用于内存存储。即使例外说，服务器不能被发现，我可以证实它的存在，它是可达的，因为示例应用程序不检查第一选择连接字符串时，并且成功：

using (var connection = new SqlConnection(connectionString)) 
{ 
    // It worked, we can save this as our connection string 
    return connectionString; 
} 

是问题可能是因为它试图用SqlClient访问MySQL数据库？

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

Answer 1

这不是一个MassTransit问题，而是实体框架问题。它应该是这样的：

如何在MySQL中使用实体框架。

你例外清楚地说：System.Data.SqlClient是扔它。这是SQL Server客户端。它还说：

Could not open a connection to SQL Server

关于如何配置EF和MySQL，可以参考documentation。一般情况下，你需要安装MySql.Data.Entity NuGet包，并告诉EF，你正在使用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>