Question

I tried to run my unit tests with C# Sqlite instead of going to a real database or mocking the hell out of our database layer using this blog post as guideline: Nhibernate C# Sqlite.

Unfortunately NHibernate requires a connection to be an DbConnection which is not provided by the C#-Sqlite Driver. I looked into the source code and noticed the following code:

#if NET_2_0
public class SqliteConnection : DbConnection, ICloneable
#else
    public class SqliteConnection : IDbConnection, ICloneable
#endif

Aparently the author decided to discontinue the “old” base classes and use the IDbConnection, IDbTransaction, … interfaces instead.

Changing the code is no option because this would be equal to write a new client which has to be tested and maintained.

Does anyone know an easy solution to get the current version of c#sqlite work with NHibernate?

Answer 1

I solved the problem using System.Data.SQLite and a custom Connection Provider:

public class SqLiteInMemoryConnectionProvider : DriverConnectionProvider
{
    public static IDbConnection Connection;

    public static event EventHandler ConnectionReset;

    public static void ResetConnection()
    {
        if(Connection == null) return;

        Connection.Close();
        Connection.Open();

        if(ConnectionReset != null) ConnectionReset(null, new EventArgs());
    }

    public override IDbConnection GetConnection()
    {
        if (Connection == null)
        {
            Connection = base.GetConnection();
        }
        if (Connection.State != ConnectionState.Open)
        {
            Connection.Open();
        }
        return Connection;
    }

    public override void CloseConnection(IDbConnection conn) { }
}

Differences to Stefan Steineggers solution are I am closing and reopening the session to reset because NHibernate could not aquire a new connection if I just disposed it.
Further I added an event to use in my factory class to rebuild the session factory (which exports our schema to the database)

SqLiteInMemoryConnectionProvider.ConnectionReset += (s, _) => RebuildSessionFactory();