Timeout error on running Scaffold-DbContext

0

We use data-first approach, and use Scaffol-Dbcontext to reverse-engineer the data context.

Database is MySQL and we use Pomelo as provider.

It has been working fine for 283 database versions, but now the command crashes with the error:

The Command Timeout expired before the operation completed.

This is the command I use:

Scaffold-DbContext "server=localhost;userid=user;pwd=pass;port=3306;database=db_name;sslmode=none;" "Pomelo.EntityFrameworkCore.MySql" -d -o "OutputFolder" -v -f -context "ContextName"

And this is the full stack trace:

MySql.Data.MySqlClient.MySqlException (0x80004005): The Command Timeout expired before the operation completed. ---> MySql.Data.MySqlClient.MySqlException (0x80004005): The Command Timeout expired before the operation completed.
   at MySqlConnector.Protocol.Serialization.BufferedByteReader.ReadBytesAsync(IByteHandler byteHandler, ArraySegment`1 buffer, Int32 totalBytesToRead, IOBehavior ioBehavior) in C:\projects\mysqlconnector\src\MySqlConnector\Protocol\Serialization\BufferedByteReader.cs:line 36
   at MySqlConnector.Protocol.Serialization.ProtocolUtility.ReadPacketAsync(BufferedByteReader bufferedByteReader, IByteHandler byteHandler, Func`1 getNextSequenceNumber, ProtocolErrorBehavior protocolErrorBehavior, IOBehavior ioBehavior) in C:\projects\mysqlconnector\src\MySqlConnector\Protocol\Serialization\ProtocolUtility.cs:line 406
   at MySqlConnector.Protocol.Serialization.ProtocolUtility.DoReadPayloadAsync(BufferedByteReader bufferedByteReader, IByteHandler byteHandler, Func`1 getNextSequenceNumber, ArraySegmentHolder`1 previousPayloads, ProtocolErrorBehavior protocolErrorBehavior, IOBehavior ioBehavior) in C:\projects\mysqlconnector\src\MySqlConnector\Protocol\Serialization\ProtocolUtility.cs:line 459
   at MySqlConnector.Protocol.Serialization.StandardPayloadHandler.ReadPayloadAsync(ArraySegmentHolder`1 cache, ProtocolErrorBehavior protocolErrorBehavior, IOBehavior ioBehavior) in C:\projects\mysqlconnector\src\MySqlConnector\Protocol\Serialization\StandardPayloadHandler.cs:line 37
   at MySqlConnector.Core.ServerSession.ReceiveReplyAsync(IOBehavior ioBehavior, CancellationToken cancellationToken) in C:\projects\mysqlconnector\src\MySqlConnector\Core\ServerSession.cs:line 645
--- End of stack trace from previous location where exception was thrown ---
   at MySqlConnector.Core.ServerSession.TryAsyncContinuation(Task`1 task) in C:\projects\mysqlconnector\src\MySqlConnector\Core\ServerSession.cs:line 1230
   at System.Threading.Tasks.ContinuationResultTaskFromResultTask`2.InnerInvoke()
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
--- End of stack trace from previous location where exception was thrown ---
   at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot)
--- End of stack trace from previous location where exception was thrown ---
   at MySqlConnector.Core.ResultSet.ReadResultSetHeaderAsync(IOBehavior ioBehavior) in C:\projects\mysqlconnector\src\MySqlConnector\Core\ResultSet.cs:line 42
   at MySql.Data.MySqlClient.MySqlDataReader.ActivateResultSet(ResultSet resultSet) in C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlDataReader.cs:line 74
   at MySql.Data.MySqlClient.MySqlDataReader.ReadFirstResultSetAsync(IOBehavior ioBehavior) in C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlDataReader.cs:line 299
   at MySql.Data.MySqlClient.MySqlDataReader.CreateAsync(MySqlCommand command, CommandBehavior behavior, ResultSetProtocol resultSetProtocol, IOBehavior ioBehavior) in C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlDataReader.cs:line 284
   at MySqlConnector.Core.TextCommandExecutor.ExecuteReaderAsync(String commandText, MySqlParameterCollection parameterCollection, CommandBehavior behavior, IOBehavior ioBehavior, CancellationToken cancellationToken) in C:\projects\mysqlconnector\src\MySqlConnector\Core\TextCommandExecutor.cs:line 37
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteDbDataReader(CommandBehavior behavior) in C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlCommand.cs:line 252
   at Pomelo.EntityFrameworkCore.MySql.Scaffolding.Internal.MySqlDatabaseModelFactory.GetConstraints()
   at Pomelo.EntityFrameworkCore.MySql.Scaffolding.Internal.MySqlDatabaseModelFactory.Create(DbConnection connection, IEnumerable`1 tables, IEnumerable`1 schemas)
   at Pomelo.EntityFrameworkCore.MySql.Scaffolding.Internal.MySqlDatabaseModelFactory.Create(String connectionString, IEnumerable`1 tables, IEnumerable`1 schemas)
   at Microsoft.EntityFrameworkCore.Scaffolding.Internal.ReverseEngineerScaffolder.ScaffoldModel(String connectionString, IEnumerable`1 tables, IEnumerable`1 schemas, String namespace, String language, String contextDir, String contextName, ModelReverseEngineerOptions modelOptions, ModelCodeGenerationOptions codeOptions)
   at Microsoft.EntityFrameworkCore.Design.Internal.DatabaseOperations.ScaffoldContext(String provider, String connectionString, String outputDir, String outputContextDir, String dbContextClassName, IEnumerable`1 schemas, IEnumerable`1 tables, Boolean useDataAnnotations, Boolean overwriteFiles, Boolean useDatabaseNames)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.ScaffoldContextImpl(String provider, String connectionString, String outputDir, String outputDbContextDir, String dbContextClassName, IEnumerable`1 schemaFilters, IEnumerable`1 tableFilters, Boolean useDataAnnotations, Boolean overwriteFiles, Boolean useDatabaseNames)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.ScaffoldContext.<>c__DisplayClass0_1.<.ctor>b__0()
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.<>c__DisplayClass3_0`1.<Execute>b__0()
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.Execute(Action action)

Related package versions:

  • Microsoft.AspNetCore.All 2.1.4
  • Pomelo.EntityFrameworkCore.MySql 2.1.2

It's important to note that this only happens on my computer (VS Professional 2017 v15.8.5). The other coworkers can run the same command, with a backup of my database, without any error.

Can you point me in the right direction? So far I have tested (without success):

  • Update all packages.
  • Update Visual Studio
  • Delete nuget folder and restore packages
  • Tried with several databases (some work, some don't, but not sure what's the difference between them)
  • Added the "Connect timeout=300" property to the connection string (same error, but it takes 5 minutes)
c#
mysql
entity-framework-core
asked on Stack Overflow Sep 21, 2018 by Dídac Punyet • edited Aug 20, 2019 by Dharman

2 Answers

0

Sorry this answer doesn't solve the problem as expected, but i needed this working for monday, so I went down the cowards road:

Uninstalling everything related to Visual Studio and MySQL and reinstall again makes everything work fine.

It also decreased the time needed by Scaffold-DbContext to run from ~3 minutes to ~10 seconds.

Just for the record, my last test proved that importing only 1 table with more than 5 FK constraints, the process fails. Removing ANY of the FK makes the process work...

My intuition tells me some corrupted package somewhere was causing this.

answered on Stack Overflow Sep 23, 2018 by Dídac Punyet
0

Next time, try to add

  1. Connection Timeout=300 (Time in seconds)
  2. default command timeout=300 (Time in seconds)

to your connection string as following:

dotnet ef dbcontext scaffold "server=simycotest.ddns.net;userid=xxxxx;password=xxxxx;database=xxxxx;Connection Timeout=300;default command timeout=300" "Pomelo.EntityFrameworkCore.MySql" -o .\DbModels -f

For more info about connection string in MySql


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