MassTransit傳奇堅持與實體框架和MySQL

Question

我正在開發使用MassTransit（與RabbitMQ）和自動匿名的傳奇。我使用EntityFramework作爲我的商店引擎和MySQL作爲我的數據庫。每次我嘗試運行傳奇並將其狀態存儲在數據庫中時，EF和MySQL的組合都會引發異常。使用this示例應用程序並使用連接字符串連接到MySQL數據庫，可以重現問題。引發的確切例外是：

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

如果我使用本地數據庫與VS 2015而不是MySQL安裝，那麼它工作得很好。它也適用於內存存儲。即使例外說，服務器不能被發現，我可以證實它的存在，它是可達的，因爲示例應用程序不檢查第一選擇連接字符串時，並且成功：

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

是問題可能是因爲它試圖用SqlClient訪問MySQL數據庫？

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

Answer 1

這不是一個MassTransit問題，而是實體框架問題。它應該是這樣的：

如何在MySQL中使用實體框架。

你例外清楚地說：System.Data.SqlClient是扔它。這是SQL Server客戶端。它還說：

Could not open a connection to SQL Server

關於如何配置EF和MySQL，可以參考documentation。一般情況下，你需要安裝MySql.Data.Entity NuGet包，並告訴EF，你正在使用MySQL，然後配置正確的連接字符串：

<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>